109 files changed, 13112 insertions, 5493 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index a987aa1676b5..057472fbc272 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -68,14 +68,14 @@ obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o
 obj-$(CONFIG_IKCONFIG) += configs.o
 obj-$(CONFIG_RESOURCE_COUNTERS) += res_counter.o
-obj-$(CONFIG_STOP_MACHINE) += stop_machine.o
+obj-$(CONFIG_SMP) += stop_machine.o
 obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
 obj-$(CONFIG_AUDIT) += audit.o auditfilter.o audit_watch.o
 obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
 obj-$(CONFIG_GCOV_KERNEL) += gcov/
 obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
 obj-$(CONFIG_KPROBES) += kprobes.o
-obj-$(CONFIG_KGDB) += kgdb.o
+obj-$(CONFIG_KGDB) += debug/
 obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
 obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
 obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
diff --git a/kernel/acct.c b/kernel/acct.c
index e4c0e1fee9b0..385b88461c29 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -216,7 +216,6 @@ static int acct_on(char *name)
 {
         struct file *file;
         struct vfsmount *mnt;
-        int error;
         struct pid_namespace *ns;
         struct bsd_acct_struct *acct = NULL;
 
@@ -244,13 +243,6 @@ static int acct_on(char *name)
                 }
         }
 
-        error = security_acct(file);
-        if (error) {
-                kfree(acct);
-                filp_close(file, NULL);
-                return error;
-        }
-
         spin_lock(&acct_lock);
         if (ns->bacct == NULL) {
                 ns->bacct = acct;
@@ -281,7 +273,7 @@ static int acct_on(char *name)
  */
 SYSCALL_DEFINE1(acct, const char __user *, name)
 {
-        int error;
+        int error = 0;
 
         if (!capable(CAP_SYS_PACCT))
                 return -EPERM;
@@ -299,13 +291,11 @@ SYSCALL_DEFINE1(acct, const char __user *, name)
                 if (acct == NULL)
                         return 0;
 
-                error = security_acct(NULL);
-                if (!error) {
-                        spin_lock(&acct_lock);
-                        acct_file_reopen(acct, NULL, NULL);
-                        spin_unlock(&acct_lock);
-                }
+                spin_lock(&acct_lock);
+                acct_file_reopen(acct, NULL, NULL);
+                spin_unlock(&acct_lock);
         }
+
         return error;
 }
 
diff --git a/kernel/capability.c b/kernel/capability.c
index 9e4697e9b276..2f05303715a5 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -15,7 +15,6 @@
 #include <linux/syscalls.h>
 #include <linux/pid_namespace.h>
 #include <asm/uaccess.h>
-#include "cred-internals.h"
 
 /*
  * Leveraged for setting/resetting capabilities
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 6d870f2d1228..422cb19f156e 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2994,7 +2994,6 @@ static void cgroup_event_remove(struct work_struct *work)
                         remove);
         struct cgroup *cgrp = event->cgrp;
 
-        /* TODO: check return code */
         event->cft->unregister_event(cgrp, event->cft, event->eventfd);
 
         eventfd_ctx_put(event->eventfd);
@@ -3016,7 +3015,7 @@ static int cgroup_event_wake(wait_queue_t *wait, unsigned mode,
         unsigned long flags = (unsigned long)key;
 
         if (flags & POLLHUP) {
-                remove_wait_queue_locked(event->wqh, &event->wait);
+                __remove_wait_queue(event->wqh, &event->wait);
                 spin_lock(&cgrp->event_list_lock);
                 list_del(&event->list);
                 spin_unlock(&cgrp->event_list_lock);
@@ -3615,7 +3614,7 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss)
  * @ss: the subsystem to load
  *
  * This function should be called in a modular subsystem's initcall. If the
- * subsytem is built as a module, it will be assigned a new subsys_id and set
+ * subsystem is built as a module, it will be assigned a new subsys_id and set
  * up for use. If the subsystem is built-in anyway, work is delegated to the
  * simpler cgroup_init_subsys.
  */
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index e5c0244962b0..ce71ed53e88f 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -89,10 +89,10 @@ struct cgroup_subsys freezer_subsys;
 
 /* Locks taken and their ordering
  * ------------------------------
- * css_set_lock
  * cgroup_mutex (AKA cgroup_lock)
- * task->alloc_lock (AKA task_lock)
  * freezer->lock
+ * css_set_lock
+ * task->alloc_lock (AKA task_lock)
  * task->sighand->siglock
  *
  * cgroup code forces css_set_lock to be taken before task->alloc_lock
@@ -100,33 +100,38 @@ struct cgroup_subsys freezer_subsys;
  * freezer_create(), freezer_destroy():
  * cgroup_mutex [ by cgroup core ]
  *
- * can_attach():
- * cgroup_mutex
+ * freezer_can_attach():
+ * cgroup_mutex (held by caller of can_attach)
  *
- * cgroup_frozen():
+ * cgroup_freezing_or_frozen():
  * task->alloc_lock (to get task's cgroup)
  *
  * freezer_fork() (preserving fork() performance means can't take cgroup_mutex):
- * task->alloc_lock (to get task's cgroup)
  * freezer->lock
  *  sighand->siglock (if the cgroup is freezing)
  *
  * freezer_read():
  * cgroup_mutex
  *  freezer->lock
+ *   write_lock css_set_lock (cgroup iterator start)
+ *    task->alloc_lock
  *   read_lock css_set_lock (cgroup iterator start)
  *
  * freezer_write() (freeze):
  * cgroup_mutex
  *  freezer->lock
+ *   write_lock css_set_lock (cgroup iterator start)
+ *    task->alloc_lock
  *   read_lock css_set_lock (cgroup iterator start)
- *    sighand->siglock
+ *    sighand->siglock (fake signal delivery inside freeze_task())
  *
  * freezer_write() (unfreeze):
  * cgroup_mutex
  *  freezer->lock
+ *   write_lock css_set_lock (cgroup iterator start)
+ *    task->alloc_lock
  *   read_lock css_set_lock (cgroup iterator start)
- *    task->alloc_lock (to prevent races with freeze_task())
+ *    task->alloc_lock (inside thaw_process(), prevents race with refrigerator())
  *     sighand->siglock
  */
 static struct cgroup_subsys_state *freezer_create(struct cgroup_subsys *ss,
diff --git a/kernel/compat.c b/kernel/compat.c
index 7f40e9275fd9..5adab05a3172 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -495,29 +495,26 @@ asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
 {
         int ret;
         cpumask_var_t mask;
-        unsigned long *k;
-        unsigned int min_length = cpumask_size();
-
-        if (nr_cpu_ids <= BITS_PER_COMPAT_LONG)
-                min_length = sizeof(compat_ulong_t);
 
-        if (len < min_length)
+        if ((len * BITS_PER_BYTE) < nr_cpu_ids)
+                return -EINVAL;
+        if (len & (sizeof(compat_ulong_t)-1))
                 return -EINVAL;
 
         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
                 return -ENOMEM;
 
         ret = sched_getaffinity(pid, mask);
-        if (ret < 0)
-                goto out;
+        if (ret == 0) {
+                size_t retlen = min_t(size_t, len, cpumask_size());
 
-        k = cpumask_bits(mask);
-        ret = compat_put_bitmap(user_mask_ptr, k, min_length * 8);
-        if (ret == 0)
-                ret = min_length;
-
-out:
+                if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
+                        ret = -EFAULT;
+                else
+                        ret = retlen;
+        }
         free_cpumask_var(mask);
+
         return ret;
 }
 
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 25bba73b1be3..3097382eb44a 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -20,6 +20,20 @@
 /* Serializes the updates to cpu_online_mask, cpu_present_mask */
 static DEFINE_MUTEX(cpu_add_remove_lock);
 
+/*
+ * The following two API's must be used when attempting
+ * to serialize the updates to cpu_online_mask, cpu_present_mask.
+ */
+void cpu_maps_update_begin(void)
+{
+        mutex_lock(&cpu_add_remove_lock);
+}
+
+void cpu_maps_update_done(void)
+{
+        mutex_unlock(&cpu_add_remove_lock);
+}
+
 static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain);
 
 /* If set, cpu_up and cpu_down will return -EBUSY and do nothing.
@@ -27,6 +41,8 @@ static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain);
  */
 static int cpu_hotplug_disabled;
 
+#ifdef CONFIG_HOTPLUG_CPU
+
 static struct {
         struct task_struct *active_writer;
         struct mutex lock; /* Synchronizes accesses to refcount, */
@@ -41,8 +57,6 @@ static struct {
         .refcount = 0,
 };
 
-#ifdef CONFIG_HOTPLUG_CPU
-
 void get_online_cpus(void)
 {
         might_sleep();
@@ -67,22 +81,6 @@ void put_online_cpus(void)
 }
 EXPORT_SYMBOL_GPL(put_online_cpus);
 
-#endif  /* CONFIG_HOTPLUG_CPU */
-
-/*
- * The following two API's must be used when attempting
- * to serialize the updates to cpu_online_mask, cpu_present_mask.
- */
-void cpu_maps_update_begin(void)
-{
-        mutex_lock(&cpu_add_remove_lock);
-}
-
-void cpu_maps_update_done(void)
-{
-        mutex_unlock(&cpu_add_remove_lock);
-}
-
 /*
  * This ensures that the hotplug operation can begin only when the
  * refcount goes to zero.
@@ -124,6 +122,12 @@ static void cpu_hotplug_done(void)
         cpu_hotplug.active_writer = NULL;
         mutex_unlock(&cpu_hotplug.lock);
 }
+
+#else /* #if CONFIG_HOTPLUG_CPU */
+static void cpu_hotplug_begin(void) {}
+static void cpu_hotplug_done(void) {}
+#endif  /* #esle #if CONFIG_HOTPLUG_CPU */
+
 /* Need to know about CPUs going up/down? */
 int __ref register_cpu_notifier(struct notifier_block *nb)
 {
@@ -134,8 +138,29 @@ int __ref register_cpu_notifier(struct notifier_block *nb)
         return ret;
 }
 
+static int __cpu_notify(unsigned long val, void *v, int nr_to_call,
+                        int *nr_calls)
+{
+        int ret;
+
+        ret = __raw_notifier_call_chain(&cpu_chain, val, v, nr_to_call,
+                                        nr_calls);
+
+        return notifier_to_errno(ret);
+}
+
+static int cpu_notify(unsigned long val, void *v)
+{
+        return __cpu_notify(val, v, -1, NULL);
+}
+
 #ifdef CONFIG_HOTPLUG_CPU
 
+static void cpu_notify_nofail(unsigned long val, void *v)
+{
+        BUG_ON(cpu_notify(val, v));
+}
+
 EXPORT_SYMBOL(register_cpu_notifier);
 
 void __ref unregister_cpu_notifier(struct notifier_block *nb)
@@ -164,6 +189,7 @@ static inline void check_for_tasks(int cpu)
 }
 
 struct take_cpu_down_param {
+        struct task_struct *caller;
         unsigned long mod;
         void *hcpu;
 };
@@ -172,6 +198,7 @@ struct take_cpu_down_param {
 static int __ref take_cpu_down(void *_param)
 {
         struct take_cpu_down_param *param = _param;
+        unsigned int cpu = (unsigned long)param->hcpu;
         int err;
 
         /* Ensure this CPU doesn't handle any more interrupts. */
@@ -179,9 +206,10 @@ static int __ref take_cpu_down(void *_param)
         if (err < 0)
                 return err;
 
-        raw_notifier_call_chain(&cpu_chain, CPU_DYING | param->mod,
-                                param->hcpu);
+        cpu_notify(CPU_DYING | param->mod, param->hcpu);
 
+        if (task_cpu(param->caller) == cpu)
+                move_task_off_dead_cpu(cpu, param->caller);
         /* Force idle task to run as soon as we yield: it should
            immediately notice cpu is offline and die quickly. */
         sched_idle_next();
@@ -192,10 +220,10 @@ static int __ref take_cpu_down(void *_param)
 static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
 {
         int err, nr_calls = 0;
-        cpumask_var_t old_allowed;
         void *hcpu = (void *)(long)cpu;
         unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
         struct take_cpu_down_param tcd_param = {
+                .caller = current,
                 .mod = mod,
                 .hcpu = hcpu,
         };
@@ -206,38 +234,26 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
         if (!cpu_online(cpu))
                 return -EINVAL;
 
-        if (!alloc_cpumask_var(&old_allowed, GFP_KERNEL))
-                return -ENOMEM;
-
         cpu_hotplug_begin();
         set_cpu_active(cpu, false);
-        err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
-                                        hcpu, -1, &nr_calls);
-        if (err == NOTIFY_BAD) {
+        err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls);
+        if (err) {
                 set_cpu_active(cpu, true);
 
                 nr_calls--;
-                __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
-                                          hcpu, nr_calls, NULL);
+                __cpu_notify(CPU_DOWN_FAILED | mod, hcpu, nr_calls, NULL);
                 printk("%s: attempt to take down CPU %u failed\n",
                                 __func__, cpu);
-                err = -EINVAL;
                 goto out_release;
         }
 
-        /* Ensure that we are not runnable on dying cpu */
-        cpumask_copy(old_allowed, &current->cpus_allowed);
-        set_cpus_allowed_ptr(current, cpu_active_mask);
-
         err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu));
         if (err) {
                 set_cpu_active(cpu, true);
                 /* CPU didn't die: tell everyone.  Can't complain. */
-                if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
-                                            hcpu) == NOTIFY_BAD)
-                        BUG();
+                cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
 
-                goto out_allowed;
+                goto out_release;
         }
         BUG_ON(cpu_online(cpu));
 
@@ -249,22 +265,14 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
         __cpu_die(cpu);
 
         /* CPU is completely dead: tell everyone.  Too late to complain. */
-        if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD | mod,
-                                    hcpu) == NOTIFY_BAD)
-                BUG();
+        cpu_notify_nofail(CPU_DEAD | mod, hcpu);
 
         check_for_tasks(cpu);
 
-out_allowed:
-        set_cpus_allowed_ptr(current, old_allowed);
 out_release:
         cpu_hotplug_done();
-        if (!err) {
-                if (raw_notifier_call_chain(&cpu_chain, CPU_POST_DEAD | mod,
-                                            hcpu) == NOTIFY_BAD)
-                        BUG();
-        }
-        free_cpumask_var(old_allowed);
+        if (!err)
+                cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu);
         return err;
 }
 
@@ -272,9 +280,6 @@ int __ref cpu_down(unsigned int cpu)
 {
         int err;
 
-        err = stop_machine_create();
-        if (err)
-                return err;
         cpu_maps_update_begin();
 
         if (cpu_hotplug_disabled) {
@@ -286,7 +291,6 @@ int __ref cpu_down(unsigned int cpu)
 
 out:
         cpu_maps_update_done();
-        stop_machine_destroy();
         return err;
 }
 EXPORT_SYMBOL(cpu_down);
@@ -303,13 +307,11 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
                 return -EINVAL;
 
         cpu_hotplug_begin();
-        ret = __raw_notifier_call_chain(&cpu_chain, CPU_UP_PREPARE | mod, hcpu,
-                                                        -1, &nr_calls);
-        if (ret == NOTIFY_BAD) {
+        ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
+        if (ret) {
                 nr_calls--;
                 printk("%s: attempt to bring up CPU %u failed\n",
                                 __func__, cpu);
-                ret = -EINVAL;
                 goto out_notify;
         }
 
@@ -322,12 +324,11 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
         set_cpu_active(cpu, true);
 
         /* Now call notifier in preparation. */
-        raw_notifier_call_chain(&cpu_chain, CPU_ONLINE | mod, hcpu);
+        cpu_notify(CPU_ONLINE | mod, hcpu);
 
 out_notify:
         if (ret != 0)
-                __raw_notifier_call_chain(&cpu_chain,
-                                CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
+                __cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
         cpu_hotplug_done();
 
         return ret;
@@ -336,6 +337,12 @@ out_notify:
 int __cpuinit cpu_up(unsigned int cpu)
 {
         int err = 0;
+
+#ifdef  CONFIG_MEMORY_HOTPLUG
+        int nid;
+        pg_data_t       *pgdat;
+#endif
+
         if (!cpu_possible(cpu)) {
                 printk(KERN_ERR "can't online cpu %d because it is not "
                         "configured as may-hotadd at boot time\n", cpu);
@@ -346,6 +353,28 @@ int __cpuinit cpu_up(unsigned int cpu)
                 return -EINVAL;
         }
 
+#ifdef  CONFIG_MEMORY_HOTPLUG
+        nid = cpu_to_node(cpu);
+        if (!node_online(nid)) {
+                err = mem_online_node(nid);
+                if (err)
+                        return err;
+        }
+
+        pgdat = NODE_DATA(nid);
+        if (!pgdat) {
+                printk(KERN_ERR
+                        "Can't online cpu %d due to NULL pgdat\n", cpu);
+                return -ENOMEM;
+        }
+
+        if (pgdat->node_zonelists->_zonerefs->zone == NULL) {
+                mutex_lock(&zonelists_mutex);
+                build_all_zonelists(NULL);
+                mutex_unlock(&zonelists_mutex);
+        }
+#endif
+
         cpu_maps_update_begin();
 
         if (cpu_hotplug_disabled) {
@@ -367,9 +396,6 @@ int disable_nonboot_cpus(void)
 {
         int cpu, first_cpu, error;
 
-        error = stop_machine_create();
-        if (error)
-                return error;
         cpu_maps_update_begin();
         first_cpu = cpumask_first(cpu_online_mask);
         /*
@@ -400,7 +426,6 @@ int disable_nonboot_cpus(void)
                 printk(KERN_ERR "Non-boot CPUs are not disabled\n");
         }
         cpu_maps_update_done();
-        stop_machine_destroy();
         return error;
 }
 
@@ -467,7 +492,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu)
         if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus))
                 val = CPU_STARTING_FROZEN;
 #endif /* CONFIG_PM_SLEEP_SMP */
-        raw_notifier_call_chain(&cpu_chain, val, (void *)(long)cpu);
+        cpu_notify(val, (void *)(long)cpu);
 }
 
 #endif /* CONFIG_SMP */
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index d10946748ec2..02b9611eadde 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -946,16 +946,62 @@ static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from,
  * In order to avoid seeing no nodes if the old and new nodes are disjoint,
  * we structure updates as setting all new allowed nodes, then clearing newly
  * disallowed ones.
- *
- * Called with task's alloc_lock held
  */
 static void cpuset_change_task_nodemask(struct task_struct *tsk,
                                         nodemask_t *newmems)
 {
+repeat:
+        /*
+         * Allow tasks that have access to memory reserves because they have
+         * been OOM killed to get memory anywhere.
+         */
+        if (unlikely(test_thread_flag(TIF_MEMDIE)))
+                return;
+        if (current->flags & PF_EXITING) /* Let dying task have memory */
+                return;
+
+        task_lock(tsk);
         nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems);
-        mpol_rebind_task(tsk, &tsk->mems_allowed);
-        mpol_rebind_task(tsk, newmems);
+        mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1);
+
+
+        /*
+         * ensure checking ->mems_allowed_change_disable after setting all new
+         * allowed nodes.
+         *
+         * the read-side task can see an nodemask with new allowed nodes and
+         * old allowed nodes. and if it allocates page when cpuset clears newly
+         * disallowed ones continuous, it can see the new allowed bits.
+         *
+         * And if setting all new allowed nodes is after the checking, setting
+         * all new allowed nodes and clearing newly disallowed ones will be done
+         * continuous, and the read-side task may find no node to alloc page.
+         */
+        smp_mb();
+
+        /*
+         * Allocation of memory is very fast, we needn't sleep when waiting
+         * for the read-side.
+         */
+        while (ACCESS_ONCE(tsk->mems_allowed_change_disable)) {
+                task_unlock(tsk);
+                if (!task_curr(tsk))
+                        yield();
+                goto repeat;
+        }
+
+        /*
+         * ensure checking ->mems_allowed_change_disable before clearing all new
+         * disallowed nodes.
+         *
+         * if clearing newly disallowed bits before the checking, the read-side
+         * task may find no node to alloc page.
+         */
+        smp_mb();
+
+        mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP2);
         tsk->mems_allowed = *newmems;
+        task_unlock(tsk);
 }
 
 /*
@@ -978,9 +1024,7 @@ static void cpuset_change_nodemask(struct task_struct *p,
         cs = cgroup_cs(scan->cg);
         guarantee_online_mems(cs, newmems);
 
-        task_lock(p);
         cpuset_change_task_nodemask(p, newmems);
-        task_unlock(p);
 
         NODEMASK_FREE(newmems);
 
@@ -1383,9 +1427,7 @@ static void cpuset_attach_task(struct task_struct *tsk, nodemask_t *to,
         err = set_cpus_allowed_ptr(tsk, cpus_attach);
         WARN_ON_ONCE(err);
 
-        task_lock(tsk);
         cpuset_change_task_nodemask(tsk, to);
-        task_unlock(tsk);
         cpuset_update_task_spread_flag(cs, tsk);
 
 }
@@ -2182,19 +2224,52 @@ void __init cpuset_init_smp(void)
 void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
 {
         mutex_lock(&callback_mutex);
-        cpuset_cpus_allowed_locked(tsk, pmask);
+        task_lock(tsk);
+        guarantee_online_cpus(task_cs(tsk), pmask);
+        task_unlock(tsk);
         mutex_unlock(&callback_mutex);
 }
 
-/**
- * cpuset_cpus_allowed_locked - return cpus_allowed mask from a tasks cpuset.
- * Must be called with callback_mutex held.
- **/
-void cpuset_cpus_allowed_locked(struct task_struct *tsk, struct cpumask *pmask)
+int cpuset_cpus_allowed_fallback(struct task_struct *tsk)
 {
-        task_lock(tsk);
-        guarantee_online_cpus(task_cs(tsk), pmask);
-        task_unlock(tsk);
+        const struct cpuset *cs;
+        int cpu;
+
+        rcu_read_lock();
+        cs = task_cs(tsk);
+        if (cs)
+                cpumask_copy(&tsk->cpus_allowed, cs->cpus_allowed);
+        rcu_read_unlock();
+
+        /*
+         * We own tsk->cpus_allowed, nobody can change it under us.
+         *
+         * But we used cs && cs->cpus_allowed lockless and thus can
+         * race with cgroup_attach_task() or update_cpumask() and get
+         * the wrong tsk->cpus_allowed. However, both cases imply the
+         * subsequent cpuset_change_cpumask()->set_cpus_allowed_ptr()
+         * which takes task_rq_lock().
+         *
+         * If we are called after it dropped the lock we must see all
+         * changes in tsk_cs()->cpus_allowed. Otherwise we can temporary
+         * set any mask even if it is not right from task_cs() pov,
+         * the pending set_cpus_allowed_ptr() will fix things.
+         */
+
+        cpu = cpumask_any_and(&tsk->cpus_allowed, cpu_active_mask);
+        if (cpu >= nr_cpu_ids) {
+                /*
+                 * Either tsk->cpus_allowed is wrong (see above) or it
+                 * is actually empty. The latter case is only possible
+                 * if we are racing with remove_tasks_in_empty_cpuset().
+                 * Like above we can temporary set any mask and rely on
+                 * set_cpus_allowed_ptr() as synchronization point.
+                 */
+                cpumask_copy(&tsk->cpus_allowed, cpu_possible_mask);
+                cpu = cpumask_any(cpu_active_mask);
+        }
+
+        return cpu;
 }
 
 void cpuset_init_current_mems_allowed(void)
@@ -2383,22 +2458,6 @@ int __cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
 }
 
 /**
- * cpuset_lock - lock out any changes to cpuset structures
- *
- * The out of memory (oom) code needs to mutex_lock cpusets
- * from being changed while it scans the tasklist looking for a
- * task in an overlapping cpuset.  Expose callback_mutex via this
- * cpuset_lock() routine, so the oom code can lock it, before
- * locking the task list.  The tasklist_lock is a spinlock, so
- * must be taken inside callback_mutex.
- */
-
-void cpuset_lock(void)
-{
-        mutex_lock(&callback_mutex);
-}
-
-/**
  * cpuset_unlock - release lock on cpuset changes
  *
  * Undo the lock taken in a previous cpuset_lock() call.
@@ -2410,7 +2469,8 @@ void cpuset_unlock(void)
 }
 
 /**
- * cpuset_mem_spread_node() - On which node to begin search for a page
+ * cpuset_mem_spread_node() - On which node to begin search for a file page
+ * cpuset_slab_spread_node() - On which node to begin search for a slab page
  *
  * If a task is marked PF_SPREAD_PAGE or PF_SPREAD_SLAB (as for
  * tasks in a cpuset with is_spread_page or is_spread_slab set),
@@ -2435,16 +2495,27 @@ void cpuset_unlock(void)
  * See kmem_cache_alloc_node().
  */
 
-int cpuset_mem_spread_node(void)
+static int cpuset_spread_node(int *rotor)
 {
         int node;
 
-        node = next_node(current->cpuset_mem_spread_rotor, current->mems_allowed);
+        node = next_node(*rotor, current->mems_allowed);
         if (node == MAX_NUMNODES)
                 node = first_node(current->mems_allowed);
-        current->cpuset_mem_spread_rotor = node;
+        *rotor = node;
         return node;
 }
+
+int cpuset_mem_spread_node(void)
+{
+        return cpuset_spread_node(&current->cpuset_mem_spread_rotor);
+}
+
+int cpuset_slab_spread_node(void)
+{
+        return cpuset_spread_node(&current->cpuset_slab_spread_rotor);
+}
+
 EXPORT_SYMBOL_GPL(cpuset_mem_spread_node);
 
 /**
diff --git a/kernel/cred-internals.h b/kernel/cred-internals.h
deleted file mode 100644
index 2dc4fc2d0bf1..000000000000
--- a/kernel/cred-internals.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Internal credentials stuff
- *
- * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public Licence
- * as published by the Free Software Foundation; either version
- * 2 of the Licence, or (at your option) any later version.
- */
-
-/*
- * user.c
- */
-static inline void sched_switch_user(struct task_struct *p)
-{
-#ifdef CONFIG_USER_SCHED
-        sched_move_task(p);
-#endif  /* CONFIG_USER_SCHED */
-}
-
diff --git a/kernel/cred.c b/kernel/cred.c
index 62af1816c235..a2d5504fbcc2 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -17,7 +17,6 @@
 #include <linux/init_task.h>
 #include <linux/security.h>
 #include <linux/cn_proc.h>
-#include "cred-internals.h"
 
 #if 0
 #define kdebug(FMT, ...) \
@@ -348,66 +347,6 @@ struct cred *prepare_exec_creds(void)
 }
 
 /*
- * prepare new credentials for the usermode helper dispatcher
- */
-struct cred *prepare_usermodehelper_creds(void)
-{
-#ifdef CONFIG_KEYS
-        struct thread_group_cred *tgcred = NULL;
-#endif
-        struct cred *new;
-
-#ifdef CONFIG_KEYS
-        tgcred = kzalloc(sizeof(*new->tgcred), GFP_ATOMIC);
-        if (!tgcred)
-                return NULL;
-#endif
-
-        new = kmem_cache_alloc(cred_jar, GFP_ATOMIC);
-        if (!new)
-                goto free_tgcred;
-
-        kdebug("prepare_usermodehelper_creds() alloc %p", new);
-
-        memcpy(new, &init_cred, sizeof(struct cred));
-
-        atomic_set(&new->usage, 1);
-        set_cred_subscribers(new, 0);
-        get_group_info(new->group_info);
-        get_uid(new->user);
-
-#ifdef CONFIG_KEYS
-        new->thread_keyring = NULL;
-        new->request_key_auth = NULL;
-        new->jit_keyring = KEY_REQKEY_DEFL_DEFAULT;
-
-        atomic_set(&tgcred->usage, 1);
-        spin_lock_init(&tgcred->lock);
-        new->tgcred = tgcred;
-#endif
-
-#ifdef CONFIG_SECURITY
-        new->security = NULL;
-#endif
-        if (security_prepare_creds(new, &init_cred, GFP_ATOMIC) < 0)
-                goto error;
-        validate_creds(new);
-
-        BUG_ON(atomic_read(&new->usage) != 1);
-        return new;
-
-error:
-        put_cred(new);
-        return NULL;
-
-free_tgcred:
-#ifdef CONFIG_KEYS
-        kfree(tgcred);
-#endif
-        return NULL;
-}
-
-/*
  * Copy credentials for the new process created by fork()
  *
  * We share if we can, but under some circumstances we have to generate a new
@@ -523,8 +462,6 @@ int commit_creds(struct cred *new)
 #endif
         BUG_ON(atomic_read(&new->usage) < 1);
 
-        security_commit_creds(new, old);
-
         get_cred(new); /* we will require a ref for the subj creds too */
 
         /* dumpability changes */
@@ -560,8 +497,6 @@ int commit_creds(struct cred *new)
                 atomic_dec(&old->user->processes);
         alter_cred_subscribers(old, -2);
 
-        sched_switch_user(task);
-
         /* send notifications */
         if (new->uid   != old->uid  ||
             new->euid  != old->euid ||
diff --git a/kernel/debug/Makefile b/kernel/debug/Makefile
new file mode 100644
index 000000000000..a85edc339985
--- /dev/null
+++ b/kernel/debug/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for the linux kernel debugger
+#
+
+obj-$(CONFIG_KGDB) += debug_core.o gdbstub.o
+obj-$(CONFIG_KGDB_KDB) += kdb/
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
new file mode 100644
index 000000000000..5cb7cd1de10c
--- /dev/null
+++ b/kernel/debug/debug_core.c
@@ -0,0 +1,983 @@
+/*
+ * Kernel Debug Core
+ *
+ * Maintainer: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (C) 2000-2001 VERITAS Software Corporation.
+ * Copyright (C) 2002-2004 Timesys Corporation
+ * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com>
+ * Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
+ * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
+ * Copyright (C) 2005-2009 Wind River Systems, Inc.
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *
+ * Contributors at various stages not listed above:
+ *  Jason Wessel ( jason.wessel@windriver.com )
+ *  George Anzinger <george@mvista.com>
+ *  Anurekh Saxena (anurekh.saxena@timesys.com)
+ *  Lake Stevens Instrument Division (Glenn Engel)
+ *  Jim Kingdon, Cygnus Support.
+ *
+ * Original KGDB stub: David Grothe <dave@gcom.com>,
+ * Tigran Aivazian <tigran@sco.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+#include <linux/pid_namespace.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/console.h>
+#include <linux/threads.h>
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/sysrq.h>
+#include <linux/init.h>
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/pid.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+
+#include <asm/cacheflush.h>
+#include <asm/byteorder.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+
+#include "debug_core.h"
+
+static int kgdb_break_asap;
+
+struct debuggerinfo_struct kgdb_info[NR_CPUS];
+
+/**
+ * kgdb_connected - Is a host GDB connected to us?
+ */
+int                             kgdb_connected;
+EXPORT_SYMBOL_GPL(kgdb_connected);
+
+/* All the KGDB handlers are installed */
+int                     kgdb_io_module_registered;
+
+/* Guard for recursive entry */
+static int                      exception_level;
+
+struct kgdb_io          *dbg_io_ops;
+static DEFINE_SPINLOCK(kgdb_registration_lock);
+
+/* kgdb console driver is loaded */
+static int kgdb_con_registered;
+/* determine if kgdb console output should be used */
+static int kgdb_use_con;
+/* Flag for alternate operations for early debugging */
+bool dbg_is_early = true;
+/* Next cpu to become the master debug core */
+int dbg_switch_cpu;
+
+/* Use kdb or gdbserver mode */
+int dbg_kdb_mode = 1;
+
+static int __init opt_kgdb_con(char *str)
+{
+        kgdb_use_con = 1;
+        return 0;
+}
+
+early_param("kgdbcon", opt_kgdb_con);
+
+module_param(kgdb_use_con, int, 0644);
+
+/*
+ * Holds information about breakpoints in a kernel. These breakpoints are
+ * added and removed by gdb.
+ */
+static struct kgdb_bkpt         kgdb_break[KGDB_MAX_BREAKPOINTS] = {
+        [0 ... KGDB_MAX_BREAKPOINTS-1] = { .state = BP_UNDEFINED }
+};
+
+/*
+ * The CPU# of the active CPU, or -1 if none:
+ */
+atomic_t                        kgdb_active = ATOMIC_INIT(-1);
+EXPORT_SYMBOL_GPL(kgdb_active);
+
+/*
+ * We use NR_CPUs not PERCPU, in case kgdb is used to debug early
+ * bootup code (which might not have percpu set up yet):
+ */
+static atomic_t                 passive_cpu_wait[NR_CPUS];
+static atomic_t                 cpu_in_kgdb[NR_CPUS];
+static atomic_t                 kgdb_break_tasklet_var;
+atomic_t                        kgdb_setting_breakpoint;
+
+struct task_struct              *kgdb_usethread;
+struct task_struct              *kgdb_contthread;
+
+int                             kgdb_single_step;
+static pid_t                    kgdb_sstep_pid;
+
+/* to keep track of the CPU which is doing the single stepping*/
+atomic_t                        kgdb_cpu_doing_single_step = ATOMIC_INIT(-1);
+
+/*
+ * If you are debugging a problem where roundup (the collection of
+ * all other CPUs) is a problem [this should be extremely rare],
+ * then use the nokgdbroundup option to avoid roundup. In that case
+ * the other CPUs might interfere with your debugging context, so
+ * use this with care:
+ */
+static int kgdb_do_roundup = 1;
+
+static int __init opt_nokgdbroundup(char *str)
+{
+        kgdb_do_roundup = 0;
+
+        return 0;
+}
+
+early_param("nokgdbroundup", opt_nokgdbroundup);
+
+/*
+ * Finally, some KGDB code :-)
+ */
+
+/*
+ * Weak aliases for breakpoint management,
+ * can be overriden by architectures when needed:
+ */
+int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr)
+{
+        int err;
+
+        err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE);
+        if (err)
+                return err;
+
+        return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr,
+                                  BREAK_INSTR_SIZE);
+}
+
+int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle)
+{
+        return probe_kernel_write((char *)addr,
+                                  (char *)bundle, BREAK_INSTR_SIZE);
+}
+
+int __weak kgdb_validate_break_address(unsigned long addr)
+{
+        char tmp_variable[BREAK_INSTR_SIZE];
+        int err;
+        /* Validate setting the breakpoint and then removing it.  In the
+         * remove fails, the kernel needs to emit a bad message because we
+         * are deep trouble not being able to put things back the way we
+         * found them.
+         */
+        err = kgdb_arch_set_breakpoint(addr, tmp_variable);
+        if (err)
+                return err;
+        err = kgdb_arch_remove_breakpoint(addr, tmp_variable);
+        if (err)
+                printk(KERN_ERR "KGDB: Critical breakpoint error, kernel "
+                   "memory destroyed at: %lx", addr);
+        return err;
+}
+
+unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs)
+{
+        return instruction_pointer(regs);
+}
+
+int __weak kgdb_arch_init(void)
+{
+        return 0;
+}
+
+int __weak kgdb_skipexception(int exception, struct pt_regs *regs)
+{
+        return 0;
+}
+
+/**
+ *      kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
+ *      @regs: Current &struct pt_regs.
+ *
+ *      This function will be called if the particular architecture must
+ *      disable hardware debugging while it is processing gdb packets or
+ *      handling exception.
+ */
+void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
+{
+}
+
+/*
+ * Some architectures need cache flushes when we set/clear a
+ * breakpoint:
+ */
+static void kgdb_flush_swbreak_addr(unsigned long addr)
+{
+        if (!CACHE_FLUSH_IS_SAFE)
+                return;
+
+        if (current->mm && current->mm->mmap_cache) {
+                flush_cache_range(current->mm->mmap_cache,
+                                  addr, addr + BREAK_INSTR_SIZE);
+        }
+        /* Force flush instruction cache if it was outside the mm */
+        flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
+}
+
+/*
+ * SW breakpoint management:
+ */
+int dbg_activate_sw_breakpoints(void)
+{
+        unsigned long addr;
+        int error;
+        int ret = 0;
+        int i;
+
+        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                if (kgdb_break[i].state != BP_SET)
+                        continue;
+
+                addr = kgdb_break[i].bpt_addr;
+                error = kgdb_arch_set_breakpoint(addr,
+                                kgdb_break[i].saved_instr);
+                if (error) {
+                        ret = error;
+                        printk(KERN_INFO "KGDB: BP install failed: %lx", addr);
+                        continue;
+                }
+
+                kgdb_flush_swbreak_addr(addr);
+                kgdb_break[i].state = BP_ACTIVE;
+        }
+        return ret;
+}
+
+int dbg_set_sw_break(unsigned long addr)
+{
+        int err = kgdb_validate_break_address(addr);
+        int breakno = -1;
+        int i;
+
+        if (err)
+                return err;
+
+        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                if ((kgdb_break[i].state == BP_SET) &&
+                                        (kgdb_break[i].bpt_addr == addr))
+                        return -EEXIST;
+        }
+        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                if (kgdb_break[i].state == BP_REMOVED &&
+                                        kgdb_break[i].bpt_addr == addr) {
+                        breakno = i;
+                        break;
+                }
+        }
+
+        if (breakno == -1) {
+                for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                        if (kgdb_break[i].state == BP_UNDEFINED) {
+                                breakno = i;
+                                break;
+                        }
+                }
+        }
+
+        if (breakno == -1)
+                return -E2BIG;
+
+        kgdb_break[breakno].state = BP_SET;
+        kgdb_break[breakno].type = BP_BREAKPOINT;
+        kgdb_break[breakno].bpt_addr = addr;
+
+        return 0;
+}
+
+int dbg_deactivate_sw_breakpoints(void)
+{
+        unsigned long addr;
+        int error;
+        int ret = 0;
+        int i;
+
+        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                if (kgdb_break[i].state != BP_ACTIVE)
+                        continue;
+                addr = kgdb_break[i].bpt_addr;
+                error = kgdb_arch_remove_breakpoint(addr,
+                                        kgdb_break[i].saved_instr);
+                if (error) {
+                        printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr);
+                        ret = error;
+                }
+
+                kgdb_flush_swbreak_addr(addr);
+                kgdb_break[i].state = BP_SET;
+        }
+        return ret;
+}
+
+int dbg_remove_sw_break(unsigned long addr)
+{
+        int i;
+
+        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                if ((kgdb_break[i].state == BP_SET) &&
+                                (kgdb_break[i].bpt_addr == addr)) {
+                        kgdb_break[i].state = BP_REMOVED;
+                        return 0;
+                }
+        }
+        return -ENOENT;
+}
+
+int kgdb_isremovedbreak(unsigned long addr)
+{
+        int i;
+
+        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                if ((kgdb_break[i].state == BP_REMOVED) &&
+                                        (kgdb_break[i].bpt_addr == addr))
+                        return 1;
+        }
+        return 0;
+}
+
+int dbg_remove_all_break(void)
+{
+        unsigned long addr;
+        int error;
+        int i;
+
+        /* Clear memory breakpoints. */
+        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+                if (kgdb_break[i].state != BP_ACTIVE)
+                        goto setundefined;
+                addr = kgdb_break[i].bpt_addr;
+                error = kgdb_arch_remove_breakpoint(addr,
+                                kgdb_break[i].saved_instr);
+                if (error)
+                        printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n",
+                           addr);
+setundefined:
+                kgdb_break[i].state = BP_UNDEFINED;
+        }
+
+        /* Clear hardware breakpoints. */
+        if (arch_kgdb_ops.remove_all_hw_break)
+                arch_kgdb_ops.remove_all_hw_break();
+
+        return 0;
+}
+
+/*
+ * Return true if there is a valid kgdb I/O module.  Also if no
+ * debugger is attached a message can be printed to the console about
+ * waiting for the debugger to attach.
+ *
+ * The print_wait argument is only to be true when called from inside
+ * the core kgdb_handle_exception, because it will wait for the
+ * debugger to attach.
+ */
+static int kgdb_io_ready(int print_wait)
+{
+        if (!dbg_io_ops)
+                return 0;
+        if (kgdb_connected)
+                return 1;
+        if (atomic_read(&kgdb_setting_breakpoint))
+                return 1;
+        if (print_wait) {
+#ifdef CONFIG_KGDB_KDB
+                if (!dbg_kdb_mode)
+                        printk(KERN_CRIT "KGDB: waiting... or $3#33 for KDB\n");
+#else
+                printk(KERN_CRIT "KGDB: Waiting for remote debugger\n");
+#endif
+        }
+        return 1;
+}
+
+static int kgdb_reenter_check(struct kgdb_state *ks)
+{
+        unsigned long addr;
+
+        if (atomic_read(&kgdb_active) != raw_smp_processor_id())
+                return 0;
+
+        /* Panic on recursive debugger calls: */
+        exception_level++;
+        addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
+        dbg_deactivate_sw_breakpoints();
+
+        /*
+         * If the break point removed ok at the place exception
+         * occurred, try to recover and print a warning to the end
+         * user because the user planted a breakpoint in a place that
+         * KGDB needs in order to function.
+         */
+        if (dbg_remove_sw_break(addr) == 0) {
+                exception_level = 0;
+                kgdb_skipexception(ks->ex_vector, ks->linux_regs);
+                dbg_activate_sw_breakpoints();
+                printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n",
+                        addr);
+                WARN_ON_ONCE(1);
+
+                return 1;
+        }
+        dbg_remove_all_break();
+        kgdb_skipexception(ks->ex_vector, ks->linux_regs);
+
+        if (exception_level > 1) {
+                dump_stack();
+                panic("Recursive entry to debugger");
+        }
+
+        printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n");
+#ifdef CONFIG_KGDB_KDB
+        /* Allow kdb to debug itself one level */
+        return 0;
+#endif
+        dump_stack();
+        panic("Recursive entry to debugger");
+
+        return 1;
+}
+
+static void dbg_cpu_switch(int cpu, int next_cpu)
+{
+        /* Mark the cpu we are switching away from as a slave when it
+         * holds the kgdb_active token.  This must be done so that the
+         * that all the cpus wait in for the debug core will not enter
+         * again as the master. */
+        if (cpu == atomic_read(&kgdb_active)) {
+                kgdb_info[cpu].exception_state |= DCPU_IS_SLAVE;
+                kgdb_info[cpu].exception_state &= ~DCPU_WANT_MASTER;
+        }
+        kgdb_info[next_cpu].exception_state |= DCPU_NEXT_MASTER;
+}
+
+static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
+{
+        unsigned long flags;
+        int sstep_tries = 100;
+        int error;
+        int i, cpu;
+        int trace_on = 0;
+acquirelock:
+        /*
+         * Interrupts will be restored by the 'trap return' code, except when
+         * single stepping.
+         */
+        local_irq_save(flags);
+
+        cpu = ks->cpu;
+        kgdb_info[cpu].debuggerinfo = regs;
+        kgdb_info[cpu].task = current;
+        kgdb_info[cpu].ret_state = 0;
+        kgdb_info[cpu].irq_depth = hardirq_count() >> HARDIRQ_SHIFT;
+        /*
+         * Make sure the above info reaches the primary CPU before
+         * our cpu_in_kgdb[] flag setting does:
+         */
+        atomic_inc(&cpu_in_kgdb[cpu]);
+
+        if (exception_level == 1)
+                goto cpu_master_loop;
+
+        /*
+         * CPU will loop if it is a slave or request to become a kgdb
+         * master cpu and acquire the kgdb_active lock:
+         */
+        while (1) {
+cpu_loop:
+                if (kgdb_info[cpu].exception_state & DCPU_NEXT_MASTER) {
+                        kgdb_info[cpu].exception_state &= ~DCPU_NEXT_MASTER;
+                        goto cpu_master_loop;
+                } else if (kgdb_info[cpu].exception_state & DCPU_WANT_MASTER) {
+                        if (atomic_cmpxchg(&kgdb_active, -1, cpu) == cpu)
+                                break;
+                } else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) {
+                        if (!atomic_read(&passive_cpu_wait[cpu]))
+                                goto return_normal;
+                } else {
+return_normal:
+                        /* Return to normal operation by executing any
+                         * hw breakpoint fixup.
+                         */
+                        if (arch_kgdb_ops.correct_hw_break)
+                                arch_kgdb_ops.correct_hw_break();
+                        if (trace_on)
+                                tracing_on();
+                        atomic_dec(&cpu_in_kgdb[cpu]);
+                        touch_softlockup_watchdog_sync();
+                        clocksource_touch_watchdog();
+                        local_irq_restore(flags);
+                        return 0;
+                }
+                cpu_relax();
+        }
+
+        /*
+         * For single stepping, try to only enter on the processor
+         * that was single stepping.  To gaurd against a deadlock, the
+         * kernel will only try for the value of sstep_tries before
+         * giving up and continuing on.
+         */
+        if (atomic_read(&kgdb_cpu_doing_single_step) != -1 &&
+            (kgdb_info[cpu].task &&
+             kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) {
+                atomic_set(&kgdb_active, -1);
+                touch_softlockup_watchdog_sync();
+                clocksource_touch_watchdog();
+                local_irq_restore(flags);
+
+                goto acquirelock;
+        }
+
+        if (!kgdb_io_ready(1)) {
+                kgdb_info[cpu].ret_state = 1;
+                goto kgdb_restore; /* No I/O connection, resume the system */
+        }
+
+        /*
+         * Don't enter if we have hit a removed breakpoint.
+         */
+        if (kgdb_skipexception(ks->ex_vector, ks->linux_regs))
+                goto kgdb_restore;
+
+        /* Call the I/O driver's pre_exception routine */
+        if (dbg_io_ops->pre_exception)
+                dbg_io_ops->pre_exception();
+
+        kgdb_disable_hw_debug(ks->linux_regs);
+
+        /*
+         * Get the passive CPU lock which will hold all the non-primary
+         * CPU in a spin state while the debugger is active
+         */
+        if (!kgdb_single_step) {
+                for (i = 0; i < NR_CPUS; i++)
+                        atomic_inc(&passive_cpu_wait[i]);
+        }
+
+#ifdef CONFIG_SMP
+        /* Signal the other CPUs to enter kgdb_wait() */
+        if ((!kgdb_single_step) && kgdb_do_roundup)
+                kgdb_roundup_cpus(flags);
+#endif
+
+        /*
+         * Wait for the other CPUs to be notified and be waiting for us:
+         */
+        for_each_online_cpu(i) {
+                while (kgdb_do_roundup && !atomic_read(&cpu_in_kgdb[i]))
+                        cpu_relax();
+        }
+
+        /*
+         * At this point the primary processor is completely
+         * in the debugger and all secondary CPUs are quiescent
+         */
+        dbg_deactivate_sw_breakpoints();
+        kgdb_single_step = 0;
+        kgdb_contthread = current;
+        exception_level = 0;
+        trace_on = tracing_is_on();
+        if (trace_on)
+                tracing_off();
+
+        while (1) {
+cpu_master_loop:
+                if (dbg_kdb_mode) {
+                        kgdb_connected = 1;
+                        error = kdb_stub(ks);
+                } else {
+                        error = gdb_serial_stub(ks);
+                }
+
+                if (error == DBG_PASS_EVENT) {
+                        dbg_kdb_mode = !dbg_kdb_mode;
+                        kgdb_connected = 0;
+                } else if (error == DBG_SWITCH_CPU_EVENT) {
+                        dbg_cpu_switch(cpu, dbg_switch_cpu);
+                        goto cpu_loop;
+                } else {
+                        kgdb_info[cpu].ret_state = error;
+                        break;
+                }
+        }
+
+        /* Call the I/O driver's post_exception routine */
+        if (dbg_io_ops->post_exception)
+                dbg_io_ops->post_exception();
+
+        atomic_dec(&cpu_in_kgdb[ks->cpu]);
+
+        if (!kgdb_single_step) {
+                for (i = NR_CPUS-1; i >= 0; i--)
+                        atomic_dec(&passive_cpu_wait[i]);
+                /*
+                 * Wait till all the CPUs have quit from the debugger,
+                 * but allow a CPU that hit an exception and is
+                 * waiting to become the master to remain in the debug
+                 * core.
+                 */
+                for_each_online_cpu(i) {
+                        while (kgdb_do_roundup &&
+                               atomic_read(&cpu_in_kgdb[i]) &&
+                               !(kgdb_info[i].exception_state &
+                                 DCPU_WANT_MASTER))
+                                cpu_relax();
+                }
+        }
+
+kgdb_restore:
+        if (atomic_read(&kgdb_cpu_doing_single_step) != -1) {
+                int sstep_cpu = atomic_read(&kgdb_cpu_doing_single_step);
+                if (kgdb_info[sstep_cpu].task)
+                        kgdb_sstep_pid = kgdb_info[sstep_cpu].task->pid;
+                else
+                        kgdb_sstep_pid = 0;
+        }
+        if (trace_on)
+                tracing_on();
+        /* Free kgdb_active */
+        atomic_set(&kgdb_active, -1);
+        touch_softlockup_watchdog_sync();
+        clocksource_touch_watchdog();
+        local_irq_restore(flags);
+
+        return kgdb_info[cpu].ret_state;
+}
+
+/*
+ * kgdb_handle_exception() - main entry point from a kernel exception
+ *
+ * Locking hierarchy:
+ *      interface locks, if any (begin_session)
+ *      kgdb lock (kgdb_active)
+ */
+int
+kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
+{
+        struct kgdb_state kgdb_var;
+        struct kgdb_state *ks = &kgdb_var;
+        int ret;
+
+        ks->cpu                 = raw_smp_processor_id();
+        ks->ex_vector           = evector;
+        ks->signo               = signo;
+        ks->err_code            = ecode;
+        ks->kgdb_usethreadid    = 0;
+        ks->linux_regs          = regs;
+
+        if (kgdb_reenter_check(ks))
+                return 0; /* Ouch, double exception ! */
+        kgdb_info[ks->cpu].exception_state |= DCPU_WANT_MASTER;
+        ret = kgdb_cpu_enter(ks, regs);
+        kgdb_info[ks->cpu].exception_state &= ~(DCPU_WANT_MASTER |
+                                                DCPU_IS_SLAVE);
+        return ret;
+}
+
+int kgdb_nmicallback(int cpu, void *regs)
+{
+#ifdef CONFIG_SMP
+        struct kgdb_state kgdb_var;
+        struct kgdb_state *ks = &kgdb_var;
+
+        memset(ks, 0, sizeof(struct kgdb_state));
+        ks->cpu                 = cpu;
+        ks->linux_regs          = regs;
+
+        if (!atomic_read(&cpu_in_kgdb[cpu]) &&
+            atomic_read(&kgdb_active) != -1 &&
+            atomic_read(&kgdb_active) != cpu) {
+                kgdb_info[cpu].exception_state |= DCPU_IS_SLAVE;
+                kgdb_cpu_enter(ks, regs);
+                kgdb_info[cpu].exception_state &= ~DCPU_IS_SLAVE;
+                return 0;
+        }
+#endif
+        return 1;
+}
+
+static void kgdb_console_write(struct console *co, const char *s,
+   unsigned count)
+{
+        unsigned long flags;
+
+        /* If we're debugging, or KGDB has not connected, don't try
+         * and print. */
+        if (!kgdb_connected || atomic_read(&kgdb_active) != -1 || dbg_kdb_mode)
+                return;
+
+        local_irq_save(flags);
+        gdbstub_msg_write(s, count);
+        local_irq_restore(flags);
+}
+
+static struct console kgdbcons = {
+        .name           = "kgdb",
+        .write          = kgdb_console_write,
+        .flags          = CON_PRINTBUFFER | CON_ENABLED,
+        .index          = -1,
+};
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static void sysrq_handle_dbg(int key, struct tty_struct *tty)
+{
+        if (!dbg_io_ops) {
+                printk(KERN_CRIT "ERROR: No KGDB I/O module available\n");
+                return;
+        }
+        if (!kgdb_connected) {
+#ifdef CONFIG_KGDB_KDB
+                if (!dbg_kdb_mode)
+                        printk(KERN_CRIT "KGDB or $3#33 for KDB\n");
+#else
+                printk(KERN_CRIT "Entering KGDB\n");
+#endif
+        }
+
+        kgdb_breakpoint();
+}
+
+static struct sysrq_key_op sysrq_dbg_op = {
+        .handler        = sysrq_handle_dbg,
+        .help_msg       = "debug(G)",
+        .action_msg     = "DEBUG",
+};
+#endif
+
+static int kgdb_panic_event(struct notifier_block *self,
+                            unsigned long val,
+                            void *data)
+{
+        if (dbg_kdb_mode)
+                kdb_printf("PANIC: %s\n", (char *)data);
+        kgdb_breakpoint();
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block kgdb_panic_event_nb = {
+       .notifier_call   = kgdb_panic_event,
+       .priority        = INT_MAX,
+};
+
+void __weak kgdb_arch_late(void)
+{
+}
+
+void __init dbg_late_init(void)
+{
+        dbg_is_early = false;
+        if (kgdb_io_module_registered)
+                kgdb_arch_late();
+        kdb_init(KDB_INIT_FULL);
+}
+
+static void kgdb_register_callbacks(void)
+{
+        if (!kgdb_io_module_registered) {
+                kgdb_io_module_registered = 1;
+                kgdb_arch_init();
+                if (!dbg_is_early)
+                        kgdb_arch_late();
+                atomic_notifier_chain_register(&panic_notifier_list,
+                                               &kgdb_panic_event_nb);
+#ifdef CONFIG_MAGIC_SYSRQ
+                register_sysrq_key('g', &sysrq_dbg_op);
+#endif
+                if (kgdb_use_con && !kgdb_con_registered) {
+                        register_console(&kgdbcons);
+                        kgdb_con_registered = 1;
+                }
+        }
+}
+
+static void kgdb_unregister_callbacks(void)
+{
+        /*
+         * When this routine is called KGDB should unregister from the
+         * panic handler and clean up, making sure it is not handling any
+         * break exceptions at the time.
+         */
+        if (kgdb_io_module_registered) {
+                kgdb_io_module_registered = 0;
+                atomic_notifier_chain_unregister(&panic_notifier_list,
+                                               &kgdb_panic_event_nb);
+                kgdb_arch_exit();
+#ifdef CONFIG_MAGIC_SYSRQ
+                unregister_sysrq_key('g', &sysrq_dbg_op);
+#endif
+                if (kgdb_con_registered) {
+                        unregister_console(&kgdbcons);
+                        kgdb_con_registered = 0;
+                }
+        }
+}
+
+/*
+ * There are times a tasklet needs to be used vs a compiled in
+ * break point so as to cause an exception outside a kgdb I/O module,
+ * such as is the case with kgdboe, where calling a breakpoint in the
+ * I/O driver itself would be fatal.
+ */
+static void kgdb_tasklet_bpt(unsigned long ing)
+{
+        kgdb_breakpoint();
+        atomic_set(&kgdb_break_tasklet_var, 0);
+}
+
+static DECLARE_TASKLET(kgdb_tasklet_breakpoint, kgdb_tasklet_bpt, 0);
+
+void kgdb_schedule_breakpoint(void)
+{
+        if (atomic_read(&kgdb_break_tasklet_var) ||
+                atomic_read(&kgdb_active) != -1 ||
+                atomic_read(&kgdb_setting_breakpoint))
+                return;
+        atomic_inc(&kgdb_break_tasklet_var);
+        tasklet_schedule(&kgdb_tasklet_breakpoint);
+}
+EXPORT_SYMBOL_GPL(kgdb_schedule_breakpoint);
+
+static void kgdb_initial_breakpoint(void)
+{
+        kgdb_break_asap = 0;
+
+        printk(KERN_CRIT "kgdb: Waiting for connection from remote gdb...\n");
+        kgdb_breakpoint();
+}
+
+/**
+ *      kgdb_register_io_module - register KGDB IO module
+ *      @new_dbg_io_ops: the io ops vector
+ *
+ *      Register it with the KGDB core.
+ */
+int kgdb_register_io_module(struct kgdb_io *new_dbg_io_ops)
+{
+        int err;
+
+        spin_lock(&kgdb_registration_lock);
+
+        if (dbg_io_ops) {
+                spin_unlock(&kgdb_registration_lock);
+
+                printk(KERN_ERR "kgdb: Another I/O driver is already "
+                                "registered with KGDB.\n");
+                return -EBUSY;
+        }
+
+        if (new_dbg_io_ops->init) {
+                err = new_dbg_io_ops->init();
+                if (err) {
+                        spin_unlock(&kgdb_registration_lock);
+                        return err;
+                }
+        }
+
+        dbg_io_ops = new_dbg_io_ops;
+
+        spin_unlock(&kgdb_registration_lock);
+
+        printk(KERN_INFO "kgdb: Registered I/O driver %s.\n",
+               new_dbg_io_ops->name);
+
+        /* Arm KGDB now. */
+        kgdb_register_callbacks();
+
+        if (kgdb_break_asap)
+                kgdb_initial_breakpoint();
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(kgdb_register_io_module);
+
+/**
+ *      kkgdb_unregister_io_module - unregister KGDB IO module
+ *      @old_dbg_io_ops: the io ops vector
+ *
+ *      Unregister it with the KGDB core.
+ */
+void kgdb_unregister_io_module(struct kgdb_io *old_dbg_io_ops)
+{
+        BUG_ON(kgdb_connected);
+
+        /*
+         * KGDB is no longer able to communicate out, so
+         * unregister our callbacks and reset state.
+         */
+        kgdb_unregister_callbacks();
+
+        spin_lock(&kgdb_registration_lock);
+
+        WARN_ON_ONCE(dbg_io_ops != old_dbg_io_ops);
+        dbg_io_ops = NULL;
+
+        spin_unlock(&kgdb_registration_lock);
+
+        printk(KERN_INFO
+                "kgdb: Unregistered I/O driver %s, debugger disabled.\n",
+                old_dbg_io_ops->name);
+}
+EXPORT_SYMBOL_GPL(kgdb_unregister_io_module);
+
+int dbg_io_get_char(void)
+{
+        int ret = dbg_io_ops->read_char();
+        if (ret == NO_POLL_CHAR)
+                return -1;
+        if (!dbg_kdb_mode)
+                return ret;
+        if (ret == 127)
+                return 8;
+        return ret;
+}
+
+/**
+ * kgdb_breakpoint - generate breakpoint exception
+ *
+ * This function will generate a breakpoint exception.  It is used at the
+ * beginning of a program to sync up with a debugger and can be used
+ * otherwise as a quick means to stop program execution and "break" into
+ * the debugger.
+ */
+void kgdb_breakpoint(void)
+{
+        atomic_inc(&kgdb_setting_breakpoint);
+        wmb(); /* Sync point before breakpoint */
+        arch_kgdb_breakpoint();
+        wmb(); /* Sync point after breakpoint */
+        atomic_dec(&kgdb_setting_breakpoint);
+}
+EXPORT_SYMBOL_GPL(kgdb_breakpoint);
+
+static int __init opt_kgdb_wait(char *str)
+{
+        kgdb_break_asap = 1;
+
+        kdb_init(KDB_INIT_EARLY);
+        if (kgdb_io_module_registered)
+                kgdb_initial_breakpoint();
+
+        return 0;
+}
+
+early_param("kgdbwait", opt_kgdb_wait);
diff --git a/kernel/debug/debug_core.h b/kernel/debug/debug_core.h
new file mode 100644
index 000000000000..c5d753d80f67
--- /dev/null
+++ b/kernel/debug/debug_core.h
@@ -0,0 +1,81 @@
+/*
+ * Created by: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _DEBUG_CORE_H_
+#define _DEBUG_CORE_H_
+/*
+ * These are the private implementation headers between the kernel
+ * debugger core and the debugger front end code.
+ */
+
+/* kernel debug core data structures */
+struct kgdb_state {
+        int                     ex_vector;
+        int                     signo;
+        int                     err_code;
+        int                     cpu;
+        int                     pass_exception;
+        unsigned long           thr_query;
+        unsigned long           threadid;
+        long                    kgdb_usethreadid;
+        struct pt_regs          *linux_regs;
+};
+
+/* Exception state values */
+#define DCPU_WANT_MASTER 0x1 /* Waiting to become a master kgdb cpu */
+#define DCPU_NEXT_MASTER 0x2 /* Transition from one master cpu to another */
+#define DCPU_IS_SLAVE    0x4 /* Slave cpu enter exception */
+#define DCPU_SSTEP       0x8 /* CPU is single stepping */
+
+struct debuggerinfo_struct {
+        void                    *debuggerinfo;
+        struct task_struct      *task;
+        int                     exception_state;
+        int                     ret_state;
+        int                     irq_depth;
+};
+
+extern struct debuggerinfo_struct kgdb_info[];
+
+/* kernel debug core break point routines */
+extern int dbg_remove_all_break(void);
+extern int dbg_set_sw_break(unsigned long addr);
+extern int dbg_remove_sw_break(unsigned long addr);
+extern int dbg_activate_sw_breakpoints(void);
+extern int dbg_deactivate_sw_breakpoints(void);
+
+/* polled character access to i/o module */
+extern int dbg_io_get_char(void);
+
+/* stub return value for switching between the gdbstub and kdb */
+#define DBG_PASS_EVENT -12345
+/* Switch from one cpu to another */
+#define DBG_SWITCH_CPU_EVENT -123456
+extern int dbg_switch_cpu;
+
+/* gdbstub interface functions */
+extern int gdb_serial_stub(struct kgdb_state *ks);
+extern void gdbstub_msg_write(const char *s, int len);
+
+/* gdbstub functions used for kdb <-> gdbstub transition */
+extern int gdbstub_state(struct kgdb_state *ks, char *cmd);
+extern int dbg_kdb_mode;
+
+#ifdef CONFIG_KGDB_KDB
+extern int kdb_stub(struct kgdb_state *ks);
+extern int kdb_parse(const char *cmdstr);
+#else /* ! CONFIG_KGDB_KDB */
+static inline int kdb_stub(struct kgdb_state *ks)
+{
+        return DBG_PASS_EVENT;
+}
+#endif /* CONFIG_KGDB_KDB */
+
+#endif /* _DEBUG_CORE_H_ */
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
new file mode 100644
index 000000000000..4b17b3269525
--- /dev/null
+++ b/kernel/debug/gdbstub.c
@@ -0,0 +1,1017 @@
+/*
+ * Kernel Debug Core
+ *
+ * Maintainer: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (C) 2000-2001 VERITAS Software Corporation.
+ * Copyright (C) 2002-2004 Timesys Corporation
+ * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com>
+ * Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
+ * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
+ * Copyright (C) 2005-2009 Wind River Systems, Inc.
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *
+ * Contributors at various stages not listed above:
+ *  Jason Wessel ( jason.wessel@windriver.com )
+ *  George Anzinger <george@mvista.com>
+ *  Anurekh Saxena (anurekh.saxena@timesys.com)
+ *  Lake Stevens Instrument Division (Glenn Engel)
+ *  Jim Kingdon, Cygnus Support.
+ *
+ * Original KGDB stub: David Grothe <dave@gcom.com>,
+ * Tigran Aivazian <tigran@sco.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/reboot.h>
+#include <linux/uaccess.h>
+#include <asm/cacheflush.h>
+#include <asm/unaligned.h>
+#include "debug_core.h"
+
+#define KGDB_MAX_THREAD_QUERY 17
+
+/* Our I/O buffers. */
+static char                     remcom_in_buffer[BUFMAX];
+static char                     remcom_out_buffer[BUFMAX];
+
+/* Storage for the registers, in GDB format. */
+static unsigned long            gdb_regs[(NUMREGBYTES +
+                                        sizeof(unsigned long) - 1) /
+                                        sizeof(unsigned long)];
+
+/*
+ * GDB remote protocol parser:
+ */
+
+static int hex(char ch)
+{
+        if ((ch >= 'a') && (ch <= 'f'))
+                return ch - 'a' + 10;
+        if ((ch >= '0') && (ch <= '9'))
+                return ch - '0';
+        if ((ch >= 'A') && (ch <= 'F'))
+                return ch - 'A' + 10;
+        return -1;
+}
+
+#ifdef CONFIG_KGDB_KDB
+static int gdbstub_read_wait(void)
+{
+        int ret = -1;
+        int i;
+
+        /* poll any additional I/O interfaces that are defined */
+        while (ret < 0)
+                for (i = 0; kdb_poll_funcs[i] != NULL; i++) {
+                        ret = kdb_poll_funcs[i]();
+                        if (ret > 0)
+                                break;
+                }
+        return ret;
+}
+#else
+static int gdbstub_read_wait(void)
+{
+        int ret = dbg_io_ops->read_char();
+        while (ret == NO_POLL_CHAR)
+                ret = dbg_io_ops->read_char();
+        return ret;
+}
+#endif
+/* scan for the sequence $<data>#<checksum> */
+static void get_packet(char *buffer)
+{
+        unsigned char checksum;
+        unsigned char xmitcsum;
+        int count;
+        char ch;
+
+        do {
+                /*
+                 * Spin and wait around for the start character, ignore all
+                 * other characters:
+                 */
+                while ((ch = (gdbstub_read_wait())) != '$')
+                        /* nothing */;
+
+                kgdb_connected = 1;
+                checksum = 0;
+                xmitcsum = -1;
+
+                count = 0;
+
+                /*
+                 * now, read until a # or end of buffer is found:
+                 */
+                while (count < (BUFMAX - 1)) {
+                        ch = gdbstub_read_wait();
+                        if (ch == '#')
+                                break;
+                        checksum = checksum + ch;
+                        buffer[count] = ch;
+                        count = count + 1;
+                }
+                buffer[count] = 0;
+
+                if (ch == '#') {
+                        xmitcsum = hex(gdbstub_read_wait()) << 4;
+                        xmitcsum += hex(gdbstub_read_wait());
+
+                        if (checksum != xmitcsum)
+                                /* failed checksum */
+                                dbg_io_ops->write_char('-');
+                        else
+                                /* successful transfer */
+                                dbg_io_ops->write_char('+');
+                        if (dbg_io_ops->flush)
+                                dbg_io_ops->flush();
+                }
+        } while (checksum != xmitcsum);
+}
+
+/*
+ * Send the packet in buffer.
+ * Check for gdb connection if asked for.
+ */
+static void put_packet(char *buffer)
+{
+        unsigned char checksum;
+        int count;
+        char ch;
+
+        /*
+         * $<packet info>#<checksum>.
+         */
+        while (1) {
+                dbg_io_ops->write_char('$');
+                checksum = 0;
+                count = 0;
+
+                while ((ch = buffer[count])) {
+                        dbg_io_ops->write_char(ch);
+                        checksum += ch;
+                        count++;
+                }
+
+                dbg_io_ops->write_char('#');
+                dbg_io_ops->write_char(hex_asc_hi(checksum));
+                dbg_io_ops->write_char(hex_asc_lo(checksum));
+                if (dbg_io_ops->flush)
+                        dbg_io_ops->flush();
+
+                /* Now see what we get in reply. */
+                ch = gdbstub_read_wait();
+
+                if (ch == 3)
+                        ch = gdbstub_read_wait();
+
+                /* If we get an ACK, we are done. */
+                if (ch == '+')
+                        return;
+
+                /*
+                 * If we get the start of another packet, this means
+                 * that GDB is attempting to reconnect.  We will NAK
+                 * the packet being sent, and stop trying to send this
+                 * packet.
+                 */
+                if (ch == '$') {
+                        dbg_io_ops->write_char('-');
+                        if (dbg_io_ops->flush)
+                                dbg_io_ops->flush();
+                        return;
+                }
+        }
+}
+
+static char gdbmsgbuf[BUFMAX + 1];
+
+void gdbstub_msg_write(const char *s, int len)
+{
+        char *bufptr;
+        int wcount;
+        int i;
+
+        if (len == 0)
+                len = strlen(s);
+
+        /* 'O'utput */
+        gdbmsgbuf[0] = 'O';
+
+        /* Fill and send buffers... */
+        while (len > 0) {
+                bufptr = gdbmsgbuf + 1;
+
+                /* Calculate how many this time */
+                if ((len << 1) > (BUFMAX - 2))
+                        wcount = (BUFMAX - 2) >> 1;
+                else
+                        wcount = len;
+
+                /* Pack in hex chars */
+                for (i = 0; i < wcount; i++)
+                        bufptr = pack_hex_byte(bufptr, s[i]);
+                *bufptr = '\0';
+
+                /* Move up */
+                s += wcount;
+                len -= wcount;
+
+                /* Write packet */
+                put_packet(gdbmsgbuf);
+        }
+}
+
+/*
+ * Convert the memory pointed to by mem into hex, placing result in
+ * buf.  Return a pointer to the last char put in buf (null). May
+ * return an error.
+ */
+int kgdb_mem2hex(char *mem, char *buf, int count)
+{
+        char *tmp;
+        int err;
+
+        /*
+         * We use the upper half of buf as an intermediate buffer for the
+         * raw memory copy.  Hex conversion will work against this one.
+         */
+        tmp = buf + count;
+
+        err = probe_kernel_read(tmp, mem, count);
+        if (!err) {
+                while (count > 0) {
+                        buf = pack_hex_byte(buf, *tmp);
+                        tmp++;
+                        count--;
+                }
+
+                *buf = 0;
+        }
+
+        return err;
+}
+
+/*
+ * Convert the hex array pointed to by buf into binary to be placed in
+ * mem.  Return a pointer to the character AFTER the last byte
+ * written.  May return an error.
+ */
+int kgdb_hex2mem(char *buf, char *mem, int count)
+{
+        char *tmp_raw;
+        char *tmp_hex;
+
+        /*
+         * We use the upper half of buf as an intermediate buffer for the
+         * raw memory that is converted from hex.
+         */
+        tmp_raw = buf + count * 2;
+
+        tmp_hex = tmp_raw - 1;
+        while (tmp_hex >= buf) {
+                tmp_raw--;
+                *tmp_raw = hex(*tmp_hex--);
+                *tmp_raw |= hex(*tmp_hex--) << 4;
+        }
+
+        return probe_kernel_write(mem, tmp_raw, count);
+}
+
+/*
+ * While we find nice hex chars, build a long_val.
+ * Return number of chars processed.
+ */
+int kgdb_hex2long(char **ptr, unsigned long *long_val)
+{
+        int hex_val;
+        int num = 0;
+        int negate = 0;
+
+        *long_val = 0;
+
+        if (**ptr == '-') {
+                negate = 1;
+                (*ptr)++;
+        }
+        while (**ptr) {
+                hex_val = hex(**ptr);
+                if (hex_val < 0)
+                        break;
+
+                *long_val = (*long_val << 4) | hex_val;
+                num++;
+                (*ptr)++;
+        }
+
+        if (negate)
+                *long_val = -*long_val;
+
+        return num;
+}
+
+/*
+ * Copy the binary array pointed to by buf into mem.  Fix $, #, and
+ * 0x7d escaped with 0x7d. Return -EFAULT on failure or 0 on success.
+ * The input buf is overwitten with the result to write to mem.
+ */
+static int kgdb_ebin2mem(char *buf, char *mem, int count)
+{
+        int size = 0;
+        char *c = buf;
+
+        while (count-- > 0) {
+                c[size] = *buf++;
+                if (c[size] == 0x7d)
+                        c[size] = *buf++ ^ 0x20;
+                size++;
+        }
+
+        return probe_kernel_write(mem, c, size);
+}
+
+/* Write memory due to an 'M' or 'X' packet. */
+static int write_mem_msg(int binary)
+{
+        char *ptr = &remcom_in_buffer[1];
+        unsigned long addr;
+        unsigned long length;
+        int err;
+
+        if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' &&
+            kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') {
+                if (binary)
+                        err = kgdb_ebin2mem(ptr, (char *)addr, length);
+                else
+                        err = kgdb_hex2mem(ptr, (char *)addr, length);
+                if (err)
+                        return err;
+                if (CACHE_FLUSH_IS_SAFE)
+                        flush_icache_range(addr, addr + length);
+                return 0;
+        }
+
+        return -EINVAL;
+}
+
+static void error_packet(char *pkt, int error)
+{
+        error = -error;
+        pkt[0] = 'E';
+        pkt[1] = hex_asc[(error / 10)];
+        pkt[2] = hex_asc[(error % 10)];
+        pkt[3] = '\0';
+}
+
+/*
+ * Thread ID accessors. We represent a flat TID space to GDB, where
+ * the per CPU idle threads (which under Linux all have PID 0) are
+ * remapped to negative TIDs.
+ */
+
+#define BUF_THREAD_ID_SIZE      16
+
+static char *pack_threadid(char *pkt, unsigned char *id)
+{
+        char *limit;
+
+        limit = pkt + BUF_THREAD_ID_SIZE;
+        while (pkt < limit)
+                pkt = pack_hex_byte(pkt, *id++);
+
+        return pkt;
+}
+
+static void int_to_threadref(unsigned char *id, int value)
+{
+        unsigned char *scan;
+        int i = 4;
+
+        scan = (unsigned char *)id;
+        while (i--)
+                *scan++ = 0;
+        put_unaligned_be32(value, scan);
+}
+
+static struct task_struct *getthread(struct pt_regs *regs, int tid)
+{
+        /*
+         * Non-positive TIDs are remapped to the cpu shadow information
+         */
+        if (tid == 0 || tid == -1)
+                tid = -atomic_read(&kgdb_active) - 2;
+        if (tid < -1 && tid > -NR_CPUS - 2) {
+                if (kgdb_info[-tid - 2].task)
+                        return kgdb_info[-tid - 2].task;
+                else
+                        return idle_task(-tid - 2);
+        }
+        if (tid <= 0) {
+                printk(KERN_ERR "KGDB: Internal thread select error\n");
+                dump_stack();
+                return NULL;
+        }
+
+        /*
+         * find_task_by_pid_ns() does not take the tasklist lock anymore
+         * but is nicely RCU locked - hence is a pretty resilient
+         * thing to use:
+         */
+        return find_task_by_pid_ns(tid, &init_pid_ns);
+}
+
+
+/*
+ * Remap normal tasks to their real PID,
+ * CPU shadow threads are mapped to -CPU - 2
+ */
+static inline int shadow_pid(int realpid)
+{
+        if (realpid)
+                return realpid;
+
+        return -raw_smp_processor_id() - 2;
+}
+
+/*
+ * All the functions that start with gdb_cmd are the various
+ * operations to implement the handlers for the gdbserial protocol
+ * where KGDB is communicating with an external debugger
+ */
+
+/* Handle the '?' status packets */
+static void gdb_cmd_status(struct kgdb_state *ks)
+{
+        /*
+         * We know that this packet is only sent
+         * during initial connect.  So to be safe,
+         * we clear out our breakpoints now in case
+         * GDB is reconnecting.
+         */
+        dbg_remove_all_break();
+
+        remcom_out_buffer[0] = 'S';
+        pack_hex_byte(&remcom_out_buffer[1], ks->signo);
+}
+
+/* Handle the 'g' get registers request */
+static void gdb_cmd_getregs(struct kgdb_state *ks)
+{
+        struct task_struct *thread;
+        void *local_debuggerinfo;
+        int i;
+
+        thread = kgdb_usethread;
+        if (!thread) {
+                thread = kgdb_info[ks->cpu].task;
+                local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo;
+        } else {
+                local_debuggerinfo = NULL;
+                for_each_online_cpu(i) {
+                        /*
+                         * Try to find the task on some other
+                         * or possibly this node if we do not
+                         * find the matching task then we try
+                         * to approximate the results.
+                         */
+                        if (thread == kgdb_info[i].task)
+                                local_debuggerinfo = kgdb_info[i].debuggerinfo;
+                }
+        }
+
+        /*
+         * All threads that don't have debuggerinfo should be
+         * in schedule() sleeping, since all other CPUs
+         * are in kgdb_wait, and thus have debuggerinfo.
+         */
+        if (local_debuggerinfo) {
+                pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo);
+        } else {
+                /*
+                 * Pull stuff saved during switch_to; nothing
+                 * else is accessible (or even particularly
+                 * relevant).
+                 *
+                 * This should be enough for a stack trace.
+                 */
+                sleeping_thread_to_gdb_regs(gdb_regs, thread);
+        }
+        kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES);
+}
+
+/* Handle the 'G' set registers request */
+static void gdb_cmd_setregs(struct kgdb_state *ks)
+{
+        kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES);
+
+        if (kgdb_usethread && kgdb_usethread != current) {
+                error_packet(remcom_out_buffer, -EINVAL);
+        } else {
+                gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs);
+                strcpy(remcom_out_buffer, "OK");
+        }
+}
+
+/* Handle the 'm' memory read bytes */
+static void gdb_cmd_memread(struct kgdb_state *ks)
+{
+        char *ptr = &remcom_in_buffer[1];
+        unsigned long length;
+        unsigned long addr;
+        int err;
+
+        if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' &&
+                                        kgdb_hex2long(&ptr, &length) > 0) {
+                err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length);
+                if (err)
+                        error_packet(remcom_out_buffer, err);
+        } else {
+                error_packet(remcom_out_buffer, -EINVAL);
+        }
+}
+
+/* Handle the 'M' memory write bytes */
+static void gdb_cmd_memwrite(struct kgdb_state *ks)
+{
+        int err = write_mem_msg(0);
+
+        if (err)
+                error_packet(remcom_out_buffer, err);
+        else
+                strcpy(remcom_out_buffer, "OK");
+}
+
+/* Handle the 'X' memory binary write bytes */
+static void gdb_cmd_binwrite(struct kgdb_state *ks)
+{
+        int err = write_mem_msg(1);
+
+        if (err)
+                error_packet(remcom_out_buffer, err);
+        else
+                strcpy(remcom_out_buffer, "OK");
+}
+
+/* Handle the 'D' or 'k', detach or kill packets */
+static void gdb_cmd_detachkill(struct kgdb_state *ks)
+{
+        int error;
+
+        /* The detach case */
+        if (remcom_in_buffer[0] == 'D') {
+                error = dbg_remove_all_break();
+                if (error < 0) {
+                        error_packet(remcom_out_buffer, error);
+                } else {
+                        strcpy(remcom_out_buffer, "OK");
+                        kgdb_connected = 0;
+                }
+                put_packet(remcom_out_buffer);
+        } else {
+                /*
+                 * Assume the kill case, with no exit code checking,
+                 * trying to force detach the debugger:
+                 */
+                dbg_remove_all_break();
+                kgdb_connected = 0;
+        }
+}
+
+/* Handle the 'R' reboot packets */
+static int gdb_cmd_reboot(struct kgdb_state *ks)
+{
+        /* For now, only honor R0 */
+        if (strcmp(remcom_in_buffer, "R0") == 0) {
+                printk(KERN_CRIT "Executing emergency reboot\n");
+                strcpy(remcom_out_buffer, "OK");
+                put_packet(remcom_out_buffer);
+
+                /*
+                 * Execution should not return from
+                 * machine_emergency_restart()
+                 */
+                machine_emergency_restart();
+                kgdb_connected = 0;
+
+                return 1;
+        }
+        return 0;
+}
+
+/* Handle the 'q' query packets */
+static void gdb_cmd_query(struct kgdb_state *ks)
+{
+        struct task_struct *g;
+        struct task_struct *p;
+        unsigned char thref[8];
+        char *ptr;
+        int i;
+        int cpu;
+        int finished = 0;
+
+        switch (remcom_in_buffer[1]) {
+        case 's':
+        case 'f':
+                if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) {
+                        error_packet(remcom_out_buffer, -EINVAL);
+                        break;
+                }
+
+                i = 0;
+                remcom_out_buffer[0] = 'm';
+                ptr = remcom_out_buffer + 1;
+                if (remcom_in_buffer[1] == 'f') {
+                        /* Each cpu is a shadow thread */
+                        for_each_online_cpu(cpu) {
+                                ks->thr_query = 0;
+                                int_to_threadref(thref, -cpu - 2);
+                                pack_threadid(ptr, thref);
+                                ptr += BUF_THREAD_ID_SIZE;
+                                *(ptr++) = ',';
+                                i++;
+                        }
+                }
+
+                do_each_thread(g, p) {
+                        if (i >= ks->thr_query && !finished) {
+                                int_to_threadref(thref, p->pid);
+                                pack_threadid(ptr, thref);
+                                ptr += BUF_THREAD_ID_SIZE;
+                                *(ptr++) = ',';
+                                ks->thr_query++;
+                                if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0)
+                                        finished = 1;
+                        }
+                        i++;
+                } while_each_thread(g, p);
+
+                *(--ptr) = '\0';
+                break;
+
+        case 'C':
+                /* Current thread id */
+                strcpy(remcom_out_buffer, "QC");
+                ks->threadid = shadow_pid(current->pid);
+                int_to_threadref(thref, ks->threadid);
+                pack_threadid(remcom_out_buffer + 2, thref);
+                break;
+        case 'T':
+                if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) {
+                        error_packet(remcom_out_buffer, -EINVAL);
+                        break;
+                }
+                ks->threadid = 0;
+                ptr = remcom_in_buffer + 17;
+                kgdb_hex2long(&ptr, &ks->threadid);
+                if (!getthread(ks->linux_regs, ks->threadid)) {
+                        error_packet(remcom_out_buffer, -EINVAL);
+                        break;
+                }
+                if ((int)ks->threadid > 0) {
+                        kgdb_mem2hex(getthread(ks->linux_regs,
+                                        ks->threadid)->comm,
+                                        remcom_out_buffer, 16);
+                } else {
+                        static char tmpstr[23 + BUF_THREAD_ID_SIZE];
+
+                        sprintf(tmpstr, "shadowCPU%d",
+                                        (int)(-ks->threadid - 2));
+                        kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr));
+                }
+                break;
+#ifdef CONFIG_KGDB_KDB
+        case 'R':
+                if (strncmp(remcom_in_buffer, "qRcmd,", 6) == 0) {
+                        int len = strlen(remcom_in_buffer + 6);
+
+                        if ((len % 2) != 0) {
+                                strcpy(remcom_out_buffer, "E01");
+                                break;
+                        }
+                        kgdb_hex2mem(remcom_in_buffer + 6,
+                                     remcom_out_buffer, len);
+                        len = len / 2;
+                        remcom_out_buffer[len++] = 0;
+
+                        kdb_parse(remcom_out_buffer);
+                        strcpy(remcom_out_buffer, "OK");
+                }
+                break;
+#endif
+        }
+}
+
+/* Handle the 'H' task query packets */
+static void gdb_cmd_task(struct kgdb_state *ks)
+{
+        struct task_struct *thread;
+        char *ptr;
+
+        switch (remcom_in_buffer[1]) {
+        case 'g':
+                ptr = &remcom_in_buffer[2];
+                kgdb_hex2long(&ptr, &ks->threadid);
+                thread = getthread(ks->linux_regs, ks->threadid);
+                if (!thread && ks->threadid > 0) {
+                        error_packet(remcom_out_buffer, -EINVAL);
+                        break;
+                }
+                kgdb_usethread = thread;
+                ks->kgdb_usethreadid = ks->threadid;
+                strcpy(remcom_out_buffer, "OK");
+                break;
+        case 'c':
+                ptr = &remcom_in_buffer[2];
+                kgdb_hex2long(&ptr, &ks->threadid);
+                if (!ks->threadid) {
+                        kgdb_contthread = NULL;
+                } else {
+                        thread = getthread(ks->linux_regs, ks->threadid);
+                        if (!thread && ks->threadid > 0) {
+                                error_packet(remcom_out_buffer, -EINVAL);
+                                break;
+                        }
+                        kgdb_contthread = thread;
+                }
+                strcpy(remcom_out_buffer, "OK");
+                break;
+        }
+}
+
+/* Handle the 'T' thread query packets */
+static void gdb_cmd_thread(struct kgdb_state *ks)
+{
+        char *ptr = &remcom_in_buffer[1];
+        struct task_struct *thread;
+
+        kgdb_hex2long(&ptr, &ks->threadid);
+        thread = getthread(ks->linux_regs, ks->threadid);
+        if (thread)
+                strcpy(remcom_out_buffer, "OK");
+        else
+                error_packet(remcom_out_buffer, -EINVAL);
+}
+
+/* Handle the 'z' or 'Z' breakpoint remove or set packets */
+static void gdb_cmd_break(struct kgdb_state *ks)
+{
+        /*
+         * Since GDB-5.3, it's been drafted that '0' is a software
+         * breakpoint, '1' is a hardware breakpoint, so let's do that.
+         */
+        char *bpt_type = &remcom_in_buffer[1];
+        char *ptr = &remcom_in_buffer[2];
+        unsigned long addr;
+        unsigned long length;
+        int error = 0;
+
+        if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') {
+                /* Unsupported */
+                if (*bpt_type > '4')
+                        return;
+        } else {
+                if (*bpt_type != '0' && *bpt_type != '1')
+                        /* Unsupported. */
+                        return;
+        }
+
+        /*
+         * Test if this is a hardware breakpoint, and
+         * if we support it:
+         */
+        if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT))
+                /* Unsupported. */
+                return;
+
+        if (*(ptr++) != ',') {
+                error_packet(remcom_out_buffer, -EINVAL);
+                return;
+        }
+        if (!kgdb_hex2long(&ptr, &addr)) {
+                error_packet(remcom_out_buffer, -EINVAL);
+                return;
+        }
+        if (*(ptr++) != ',' ||
+                !kgdb_hex2long(&ptr, &length)) {
+                error_packet(remcom_out_buffer, -EINVAL);
+                return;
+        }
+
+        if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0')
+                error = dbg_set_sw_break(addr);
+        else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0')
+                error = dbg_remove_sw_break(addr);
+        else if (remcom_in_buffer[0] == 'Z')
+                error = arch_kgdb_ops.set_hw_breakpoint(addr,
+                        (int)length, *bpt_type - '0');
+        else if (remcom_in_buffer[0] == 'z')
+                error = arch_kgdb_ops.remove_hw_breakpoint(addr,
+                        (int) length, *bpt_type - '0');
+
+        if (error == 0)
+                strcpy(remcom_out_buffer, "OK");
+        else
+                error_packet(remcom_out_buffer, error);
+}
+
+/* Handle the 'C' signal / exception passing packets */
+static int gdb_cmd_exception_pass(struct kgdb_state *ks)
+{
+        /* C09 == pass exception
+         * C15 == detach kgdb, pass exception
+         */
+        if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') {
+
+                ks->pass_exception = 1;
+                remcom_in_buffer[0] = 'c';
+
+        } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') {
+
+                ks->pass_exception = 1;
+                remcom_in_buffer[0] = 'D';
+                dbg_remove_all_break();
+                kgdb_connected = 0;
+                return 1;
+
+        } else {
+                gdbstub_msg_write("KGDB only knows signal 9 (pass)"
+                        " and 15 (pass and disconnect)\n"
+                        "Executing a continue without signal passing\n", 0);
+                remcom_in_buffer[0] = 'c';
+        }
+
+        /* Indicate fall through */
+        return -1;
+}
+
+/*
+ * This function performs all gdbserial command procesing
+ */
+int gdb_serial_stub(struct kgdb_state *ks)
+{
+        int error = 0;
+        int tmp;
+
+        /* Clear the out buffer. */
+        memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
+
+        if (kgdb_connected) {
+                unsigned char thref[8];
+                char *ptr;
+
+                /* Reply to host that an exception has occurred */
+                ptr = remcom_out_buffer;
+                *ptr++ = 'T';
+                ptr = pack_hex_byte(ptr, ks->signo);
+                ptr += strlen(strcpy(ptr, "thread:"));
+                int_to_threadref(thref, shadow_pid(current->pid));
+                ptr = pack_threadid(ptr, thref);
+                *ptr++ = ';';
+                put_packet(remcom_out_buffer);
+        }
+
+        kgdb_usethread = kgdb_info[ks->cpu].task;
+        ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid);
+        ks->pass_exception = 0;
+
+        while (1) {
+                error = 0;
+
+                /* Clear the out buffer. */
+                memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
+
+                get_packet(remcom_in_buffer);
+
+                switch (remcom_in_buffer[0]) {
+                case '?': /* gdbserial status */
+                        gdb_cmd_status(ks);
+                        break;
+                case 'g': /* return the value of the CPU registers */
+                        gdb_cmd_getregs(ks);
+                        break;
+                case 'G': /* set the value of the CPU registers - return OK */
+                        gdb_cmd_setregs(ks);
+                        break;
+                case 'm': /* mAA..AA,LLLL  Read LLLL bytes at address AA..AA */
+                        gdb_cmd_memread(ks);
+                        break;
+                case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */
+                        gdb_cmd_memwrite(ks);
+                        break;
+                case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */
+                        gdb_cmd_binwrite(ks);
+                        break;
+                        /* kill or detach. KGDB should treat this like a
+                         * continue.
+                         */
+                case 'D': /* Debugger detach */
+                case 'k': /* Debugger detach via kill */
+                        gdb_cmd_detachkill(ks);
+                        goto default_handle;
+                case 'R': /* Reboot */
+                        if (gdb_cmd_reboot(ks))
+                                goto default_handle;
+                        break;
+                case 'q': /* query command */
+                        gdb_cmd_query(ks);
+                        break;
+                case 'H': /* task related */
+                        gdb_cmd_task(ks);
+                        break;
+                case 'T': /* Query thread status */
+                        gdb_cmd_thread(ks);
+                        break;
+                case 'z': /* Break point remove */
+                case 'Z': /* Break point set */
+                        gdb_cmd_break(ks);
+                        break;
+#ifdef CONFIG_KGDB_KDB
+                case '3': /* Escape into back into kdb */
+                        if (remcom_in_buffer[1] == '\0') {
+                                gdb_cmd_detachkill(ks);
+                                return DBG_PASS_EVENT;
+                        }
+#endif
+                case 'C': /* Exception passing */
+                        tmp = gdb_cmd_exception_pass(ks);
+                        if (tmp > 0)
+                                goto default_handle;
+                        if (tmp == 0)
+                                break;
+                        /* Fall through on tmp < 0 */
+                case 'c': /* Continue packet */
+                case 's': /* Single step packet */
+                        if (kgdb_contthread && kgdb_contthread != current) {
+                                /* Can't switch threads in kgdb */
+                                error_packet(remcom_out_buffer, -EINVAL);
+                                break;
+                        }
+                        dbg_activate_sw_breakpoints();
+                        /* Fall through to default processing */
+                default:
+default_handle:
+                        error = kgdb_arch_handle_exception(ks->ex_vector,
+                                                ks->signo,
+                                                ks->err_code,
+                                                remcom_in_buffer,
+                                                remcom_out_buffer,
+                                                ks->linux_regs);
+                        /*
+                         * Leave cmd processing on error, detach,
+                         * kill, continue, or single step.
+                         */
+                        if (error >= 0 || remcom_in_buffer[0] == 'D' ||
+                            remcom_in_buffer[0] == 'k') {
+                                error = 0;
+                                goto kgdb_exit;
+                        }
+
+                }
+
+                /* reply to the request */
+                put_packet(remcom_out_buffer);
+        }
+
+kgdb_exit:
+        if (ks->pass_exception)
+                error = 1;
+        return error;
+}
+
+int gdbstub_state(struct kgdb_state *ks, char *cmd)
+{
+        int error;
+
+        switch (cmd[0]) {
+        case 'e':
+                error = kgdb_arch_handle_exception(ks->ex_vector,
+                                                   ks->signo,
+                                                   ks->err_code,
+                                                   remcom_in_buffer,
+                                                   remcom_out_buffer,
+                                                   ks->linux_regs);
+                return error;
+        case 's':
+        case 'c':
+                strcpy(remcom_in_buffer, cmd);
+                return 0;
+        case '?':
+                gdb_cmd_status(ks);
+                break;
+        case '\0':
+                strcpy(remcom_out_buffer, "");
+                break;
+        }
+        dbg_io_ops->write_char('+');
+        put_packet(remcom_out_buffer);
+        return 0;
+}
diff --git a/kernel/debug/kdb/.gitignore b/kernel/debug/kdb/.gitignore
new file mode 100644
index 000000000000..396d12eda9e8
--- /dev/null
+++ b/kernel/debug/kdb/.gitignore
@@ -0,0 +1 @@
+gen-kdb_cmds.c
diff --git a/kernel/debug/kdb/Makefile b/kernel/debug/kdb/Makefile
new file mode 100644
index 000000000000..d4fc58f4b88d
--- /dev/null
+++ b/kernel/debug/kdb/Makefile
@@ -0,0 +1,25 @@
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+# Copyright (c) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
+# Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+#
+
+CCVERSION       := $(shell $(CC) -v 2>&1 | sed -ne '$$p')
+obj-y := kdb_io.o kdb_main.o kdb_support.o kdb_bt.o gen-kdb_cmds.o kdb_bp.o kdb_debugger.o
+obj-$(CONFIG_KDB_KEYBOARD)    += kdb_keyboard.o
+
+clean-files := gen-kdb_cmds.c
+
+quiet_cmd_gen-kdb = GENKDB  $@
+      cmd_gen-kdb = $(AWK) 'BEGIN {print "\#include <linux/stddef.h>"; print "\#include <linux/init.h>"} \
+                /^\#/{next} \
+                /^[ \t]*$$/{next} \
+                {gsub(/"/, "\\\"", $$0); \
+                  print "static __initdata char kdb_cmd" cmds++ "[] = \"" $$0 "\\n\";"} \
+                END {print "extern char *kdb_cmds[]; char __initdata *kdb_cmds[] = {"; for (i = 0; i < cmds; ++i) {print "  kdb_cmd" i ","}; print("  NULL\n};");}' \
+                $(filter-out %/Makefile,$^) > $@#
+
+$(obj)/gen-kdb_cmds.c:  $(src)/kdb_cmds $(src)/Makefile
+        $(call cmd,gen-kdb)
diff --git a/kernel/debug/kdb/kdb_bp.c b/kernel/debug/kdb/kdb_bp.c
new file mode 100644
index 000000000000..75bd9b3ebbb7
--- /dev/null
+++ b/kernel/debug/kdb/kdb_bp.c
@@ -0,0 +1,564 @@
+/*
+ * Kernel Debugger Architecture Independent Breakpoint Handler
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ */
+
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/kdb.h>
+#include <linux/kgdb.h>
+#include <linux/smp.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include "kdb_private.h"
+
+/*
+ * Table of kdb_breakpoints
+ */
+kdb_bp_t kdb_breakpoints[KDB_MAXBPT];
+
+static void kdb_setsinglestep(struct pt_regs *regs)
+{
+        KDB_STATE_SET(DOING_SS);
+}
+
+static char *kdb_rwtypes[] = {
+        "Instruction(i)",
+        "Instruction(Register)",
+        "Data Write",
+        "I/O",
+        "Data Access"
+};
+
+static char *kdb_bptype(kdb_bp_t *bp)
+{
+        if (bp->bp_type < 0 || bp->bp_type > 4)
+                return "";
+
+        return kdb_rwtypes[bp->bp_type];
+}
+
+static int kdb_parsebp(int argc, const char **argv, int *nextargp, kdb_bp_t *bp)
+{
+        int nextarg = *nextargp;
+        int diag;
+
+        bp->bph_length = 1;
+        if ((argc + 1) != nextarg) {
+                if (strnicmp(argv[nextarg], "datar", sizeof("datar")) == 0)
+                        bp->bp_type = BP_ACCESS_WATCHPOINT;
+                else if (strnicmp(argv[nextarg], "dataw", sizeof("dataw")) == 0)
+                        bp->bp_type = BP_WRITE_WATCHPOINT;
+                else if (strnicmp(argv[nextarg], "inst", sizeof("inst")) == 0)
+                        bp->bp_type = BP_HARDWARE_BREAKPOINT;
+                else
+                        return KDB_ARGCOUNT;
+
+                bp->bph_length = 1;
+
+                nextarg++;
+
+                if ((argc + 1) != nextarg) {
+                        unsigned long len;
+
+                        diag = kdbgetularg((char *)argv[nextarg],
+                                           &len);
+                        if (diag)
+                                return diag;
+
+
+                        if (len > 8)
+                                return KDB_BADLENGTH;
+
+                        bp->bph_length = len;
+                        nextarg++;
+                }
+
+                if ((argc + 1) != nextarg)
+                        return KDB_ARGCOUNT;
+        }
+
+        *nextargp = nextarg;
+        return 0;
+}
+
+static int _kdb_bp_remove(kdb_bp_t *bp)
+{
+        int ret = 1;
+        if (!bp->bp_installed)
+                return ret;
+        if (!bp->bp_type)
+                ret = dbg_remove_sw_break(bp->bp_addr);
+        else
+                ret = arch_kgdb_ops.remove_hw_breakpoint(bp->bp_addr,
+                         bp->bph_length,
+                         bp->bp_type);
+        if (ret == 0)
+                bp->bp_installed = 0;
+        return ret;
+}
+
+static void kdb_handle_bp(struct pt_regs *regs, kdb_bp_t *bp)
+{
+        if (KDB_DEBUG(BP))
+                kdb_printf("regs->ip = 0x%lx\n", instruction_pointer(regs));
+
+        /*
+         * Setup single step
+         */
+        kdb_setsinglestep(regs);
+
+        /*
+         * Reset delay attribute
+         */
+        bp->bp_delay = 0;
+        bp->bp_delayed = 1;
+}
+
+static int _kdb_bp_install(struct pt_regs *regs, kdb_bp_t *bp)
+{
+        int ret;
+        /*
+         * Install the breakpoint, if it is not already installed.
+         */
+
+        if (KDB_DEBUG(BP))
+                kdb_printf("%s: bp_installed %d\n",
+                           __func__, bp->bp_installed);
+        if (!KDB_STATE(SSBPT))
+                bp->bp_delay = 0;
+        if (bp->bp_installed)
+                return 1;
+        if (bp->bp_delay || (bp->bp_delayed && KDB_STATE(DOING_SS))) {
+                if (KDB_DEBUG(BP))
+                        kdb_printf("%s: delayed bp\n", __func__);
+                kdb_handle_bp(regs, bp);
+                return 0;
+        }
+        if (!bp->bp_type)
+                ret = dbg_set_sw_break(bp->bp_addr);
+        else
+                ret = arch_kgdb_ops.set_hw_breakpoint(bp->bp_addr,
+                         bp->bph_length,
+                         bp->bp_type);
+        if (ret == 0) {
+                bp->bp_installed = 1;
+        } else {
+                kdb_printf("%s: failed to set breakpoint at 0x%lx\n",
+                           __func__, bp->bp_addr);
+                return 1;
+        }
+        return 0;
+}
+
+/*
+ * kdb_bp_install
+ *
+ *      Install kdb_breakpoints prior to returning from the
+ *      kernel debugger.  This allows the kdb_breakpoints to be set
+ *      upon functions that are used internally by kdb, such as
+ *      printk().  This function is only called once per kdb session.
+ */
+void kdb_bp_install(struct pt_regs *regs)
+{
+        int i;
+
+        for (i = 0; i < KDB_MAXBPT; i++) {
+                kdb_bp_t *bp = &kdb_breakpoints[i];
+
+                if (KDB_DEBUG(BP)) {
+                        kdb_printf("%s: bp %d bp_enabled %d\n",
+                                   __func__, i, bp->bp_enabled);
+                }
+                if (bp->bp_enabled)
+                        _kdb_bp_install(regs, bp);
+        }
+}
+
+/*
+ * kdb_bp_remove
+ *
+ *      Remove kdb_breakpoints upon entry to the kernel debugger.
+ *
+ * Parameters:
+ *      None.
+ * Outputs:
+ *      None.
+ * Returns:
+ *      None.
+ * Locking:
+ *      None.
+ * Remarks:
+ */
+void kdb_bp_remove(void)
+{
+        int i;
+
+        for (i = KDB_MAXBPT - 1; i >= 0; i--) {
+                kdb_bp_t *bp = &kdb_breakpoints[i];
+
+                if (KDB_DEBUG(BP)) {
+                        kdb_printf("%s: bp %d bp_enabled %d\n",
+                                   __func__, i, bp->bp_enabled);
+                }
+                if (bp->bp_enabled)
+                        _kdb_bp_remove(bp);
+        }
+}
+
+
+/*
+ * kdb_printbp
+ *
+ *      Internal function to format and print a breakpoint entry.
+ *
+ * Parameters:
+ *      None.
+ * Outputs:
+ *      None.
+ * Returns:
+ *      None.
+ * Locking:
+ *      None.
+ * Remarks:
+ */
+
+static void kdb_printbp(kdb_bp_t *bp, int i)
+{
+        kdb_printf("%s ", kdb_bptype(bp));
+        kdb_printf("BP #%d at ", i);
+        kdb_symbol_print(bp->bp_addr, NULL, KDB_SP_DEFAULT);
+
+        if (bp->bp_enabled)
+                kdb_printf("\n    is enabled");
+        else
+                kdb_printf("\n    is disabled");
+
+        kdb_printf("\taddr at %016lx, hardtype=%d installed=%d\n",
+                   bp->bp_addr, bp->bp_type, bp->bp_installed);
+
+        kdb_printf("\n");
+}
+
+/*
+ * kdb_bp
+ *
+ *      Handle the bp commands.
+ *
+ *      [bp|bph] <addr-expression> [DATAR|DATAW]
+ *
+ * Parameters:
+ *      argc    Count of arguments in argv
+ *      argv    Space delimited command line arguments
+ * Outputs:
+ *      None.
+ * Returns:
+ *      Zero for success, a kdb diagnostic if failure.
+ * Locking:
+ *      None.
+ * Remarks:
+ *
+ *      bp      Set breakpoint on all cpus.  Only use hardware assist if need.
+ *      bph     Set breakpoint on all cpus.  Force hardware register
+ */
+
+static int kdb_bp(int argc, const char **argv)
+{
+        int i, bpno;
+        kdb_bp_t *bp, *bp_check;
+        int diag;
+        int free;
+        char *symname = NULL;
+        long offset = 0ul;
+        int nextarg;
+        kdb_bp_t template = {0};
+
+        if (argc == 0) {
+                /*
+                 * Display breakpoint table
+                 */
+                for (bpno = 0, bp = kdb_breakpoints; bpno < KDB_MAXBPT;
+                     bpno++, bp++) {
+                        if (bp->bp_free)
+                                continue;
+                        kdb_printbp(bp, bpno);
+                }
+
+                return 0;
+        }
+
+        nextarg = 1;
+        diag = kdbgetaddrarg(argc, argv, &nextarg, &template.bp_addr,
+                             &offset, &symname);
+        if (diag)
+                return diag;
+        if (!template.bp_addr)
+                return KDB_BADINT;
+
+        /*
+         * Find an empty bp structure to allocate
+         */
+        free = KDB_MAXBPT;
+        for (bpno = 0, bp = kdb_breakpoints; bpno < KDB_MAXBPT; bpno++, bp++) {
+                if (bp->bp_free)
+                        break;
+        }
+
+        if (bpno == KDB_MAXBPT)
+                return KDB_TOOMANYBPT;
+
+        if (strcmp(argv[0], "bph") == 0) {
+                template.bp_type = BP_HARDWARE_BREAKPOINT;
+                diag = kdb_parsebp(argc, argv, &nextarg, &template);
+                if (diag)
+                        return diag;
+        } else {
+                template.bp_type = BP_BREAKPOINT;
+        }
+
+        /*
+         * Check for clashing breakpoints.
+         *
+         * Note, in this design we can't have hardware breakpoints
+         * enabled for both read and write on the same address.
+         */
+        for (i = 0, bp_check = kdb_breakpoints; i < KDB_MAXBPT;
+             i++, bp_check++) {
+                if (!bp_check->bp_free &&
+                    bp_check->bp_addr == template.bp_addr) {
+                        kdb_printf("You already have a breakpoint at "
+                                   kdb_bfd_vma_fmt0 "\n", template.bp_addr);
+                        return KDB_DUPBPT;
+                }
+        }
+
+        template.bp_enabled = 1;
+
+        /*
+         * Actually allocate the breakpoint found earlier
+         */
+        *bp = template;
+        bp->bp_free = 0;
+
+        kdb_printbp(bp, bpno);
+
+        return 0;
+}
+
+/*
+ * kdb_bc
+ *
+ *      Handles the 'bc', 'be', and 'bd' commands
+ *
+ *      [bd|bc|be] <breakpoint-number>
+ *      [bd|bc|be] *
+ *
+ * Parameters:
+ *      argc    Count of arguments in argv
+ *      argv    Space delimited command line arguments
+ * Outputs:
+ *      None.
+ * Returns:
+ *      Zero for success, a kdb diagnostic for failure
+ * Locking:
+ *      None.
+ * Remarks:
+ */
+static int kdb_bc(int argc, const char **argv)
+{
+        unsigned long addr;
+        kdb_bp_t *bp = NULL;
+        int lowbp = KDB_MAXBPT;
+        int highbp = 0;
+        int done = 0;
+        int i;
+        int diag = 0;
+
+        int cmd;                        /* KDBCMD_B? */
+#define KDBCMD_BC       0
+#define KDBCMD_BE       1
+#define KDBCMD_BD       2
+
+        if (strcmp(argv[0], "be") == 0)
+                cmd = KDBCMD_BE;
+        else if (strcmp(argv[0], "bd") == 0)
+                cmd = KDBCMD_BD;
+        else
+                cmd = KDBCMD_BC;
+
+        if (argc != 1)
+                return KDB_ARGCOUNT;
+
+        if (strcmp(argv[1], "*") == 0) {
+                lowbp = 0;
+                highbp = KDB_MAXBPT;
+        } else {
+                diag = kdbgetularg(argv[1], &addr);
+                if (diag)
+                        return diag;
+
+                /*
+                 * For addresses less than the maximum breakpoint number,
+                 * assume that the breakpoint number is desired.
+                 */
+                if (addr < KDB_MAXBPT) {
+                        bp = &kdb_breakpoints[addr];
+                        lowbp = highbp = addr;
+                        highbp++;
+                } else {
+                        for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT;
+                            i++, bp++) {
+                                if (bp->bp_addr == addr) {
+                                        lowbp = highbp = i;
+                                        highbp++;
+                                        break;
+                                }
+                        }
+                }
+        }
+
+        /*
+         * Now operate on the set of breakpoints matching the input
+         * criteria (either '*' for all, or an individual breakpoint).
+         */
+        for (bp = &kdb_breakpoints[lowbp], i = lowbp;
+            i < highbp;
+            i++, bp++) {
+                if (bp->bp_free)
+                        continue;
+
+                done++;
+
+                switch (cmd) {
+                case KDBCMD_BC:
+                        bp->bp_enabled = 0;
+
+                        kdb_printf("Breakpoint %d at "
+                                   kdb_bfd_vma_fmt " cleared\n",
+                                   i, bp->bp_addr);
+
+                        bp->bp_addr = 0;
+                        bp->bp_free = 1;
+
+                        break;
+                case KDBCMD_BE:
+                        bp->bp_enabled = 1;
+
+                        kdb_printf("Breakpoint %d at "
+                                   kdb_bfd_vma_fmt " enabled",
+                                   i, bp->bp_addr);
+
+                        kdb_printf("\n");
+                        break;
+                case KDBCMD_BD:
+                        if (!bp->bp_enabled)
+                                break;
+
+                        bp->bp_enabled = 0;
+
+                        kdb_printf("Breakpoint %d at "
+                                   kdb_bfd_vma_fmt " disabled\n",
+                                   i, bp->bp_addr);
+
+                        break;
+                }
+                if (bp->bp_delay && (cmd == KDBCMD_BC || cmd == KDBCMD_BD)) {
+                        bp->bp_delay = 0;
+                        KDB_STATE_CLEAR(SSBPT);
+                }
+        }
+
+        return (!done) ? KDB_BPTNOTFOUND : 0;
+}
+
+/*
+ * kdb_ss
+ *
+ *      Process the 'ss' (Single Step) and 'ssb' (Single Step to Branch)
+ *      commands.
+ *
+ *      ss
+ *      ssb
+ *
+ * Parameters:
+ *      argc    Argument count
+ *      argv    Argument vector
+ * Outputs:
+ *      None.
+ * Returns:
+ *      KDB_CMD_SS[B] for success, a kdb error if failure.
+ * Locking:
+ *      None.
+ * Remarks:
+ *
+ *      Set the arch specific option to trigger a debug trap after the next
+ *      instruction.
+ *
+ *      For 'ssb', set the trace flag in the debug trap handler
+ *      after printing the current insn and return directly without
+ *      invoking the kdb command processor, until a branch instruction
+ *      is encountered.
+ */
+
+static int kdb_ss(int argc, const char **argv)
+{
+        int ssb = 0;
+
+        ssb = (strcmp(argv[0], "ssb") == 0);
+        if (argc != 0)
+                return KDB_ARGCOUNT;
+        /*
+         * Set trace flag and go.
+         */
+        KDB_STATE_SET(DOING_SS);
+        if (ssb) {
+                KDB_STATE_SET(DOING_SSB);
+                return KDB_CMD_SSB;
+        }
+        return KDB_CMD_SS;
+}
+
+/* Initialize the breakpoint table and register breakpoint commands. */
+
+void __init kdb_initbptab(void)
+{
+        int i;
+        kdb_bp_t *bp;
+
+        /*
+         * First time initialization.
+         */
+        memset(&kdb_breakpoints, '\0', sizeof(kdb_breakpoints));
+
+        for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++)
+                bp->bp_free = 1;
+
+        kdb_register_repeat("bp", kdb_bp, "[<vaddr>]",
+                "Set/Display breakpoints", 0, KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("bl", kdb_bp, "[<vaddr>]",
+                "Display breakpoints", 0, KDB_REPEAT_NO_ARGS);
+        if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT)
+                kdb_register_repeat("bph", kdb_bp, "[<vaddr>]",
+                "[datar [length]|dataw [length]]   Set hw brk", 0, KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("bc", kdb_bc, "<bpnum>",
+                "Clear Breakpoint", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("be", kdb_bc, "<bpnum>",
+                "Enable Breakpoint", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("bd", kdb_bc, "<bpnum>",
+                "Disable Breakpoint", 0, KDB_REPEAT_NONE);
+
+        kdb_register_repeat("ss", kdb_ss, "",
+                "Single Step", 1, KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("ssb", kdb_ss, "",
+                "Single step to branch/call", 0, KDB_REPEAT_NO_ARGS);
+        /*
+         * Architecture dependent initialization.
+         */
+}
diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c
new file mode 100644
index 000000000000..2f62fe85f16a
--- /dev/null
+++ b/kernel/debug/kdb/kdb_bt.c
@@ -0,0 +1,210 @@
+/*
+ * Kernel Debugger Architecture Independent Stack Traceback
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ */
+
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/kdb.h>
+#include <linux/nmi.h>
+#include <asm/system.h>
+#include "kdb_private.h"
+
+
+static void kdb_show_stack(struct task_struct *p, void *addr)
+{
+        int old_lvl = console_loglevel;
+        console_loglevel = 15;
+        kdb_trap_printk++;
+        kdb_set_current_task(p);
+        if (addr) {
+                show_stack((struct task_struct *)p, addr);
+        } else if (kdb_current_regs) {
+#ifdef CONFIG_X86
+                show_stack(p, &kdb_current_regs->sp);
+#else
+                show_stack(p, NULL);
+#endif
+        } else {
+                show_stack(p, NULL);
+        }
+        console_loglevel = old_lvl;
+        kdb_trap_printk--;
+}
+
+/*
+ * kdb_bt
+ *
+ *      This function implements the 'bt' command.  Print a stack
+ *      traceback.
+ *
+ *      bt [<address-expression>]       (addr-exp is for alternate stacks)
+ *      btp <pid>                       Kernel stack for <pid>
+ *      btt <address-expression>        Kernel stack for task structure at
+ *                                      <address-expression>
+ *      bta [DRSTCZEUIMA]               All useful processes, optionally
+ *                                      filtered by state
+ *      btc [<cpu>]                     The current process on one cpu,
+ *                                      default is all cpus
+ *
+ *      bt <address-expression> refers to a address on the stack, that location
+ *      is assumed to contain a return address.
+ *
+ *      btt <address-expression> refers to the address of a struct task.
+ *
+ * Inputs:
+ *      argc    argument count
+ *      argv    argument vector
+ * Outputs:
+ *      None.
+ * Returns:
+ *      zero for success, a kdb diagnostic if error
+ * Locking:
+ *      none.
+ * Remarks:
+ *      Backtrack works best when the code uses frame pointers.  But even
+ *      without frame pointers we should get a reasonable trace.
+ *
+ *      mds comes in handy when examining the stack to do a manual traceback or
+ *      to get a starting point for bt <address-expression>.
+ */
+
+static int
+kdb_bt1(struct task_struct *p, unsigned long mask,
+        int argcount, int btaprompt)
+{
+        char buffer[2];
+        if (kdb_getarea(buffer[0], (unsigned long)p) ||
+            kdb_getarea(buffer[0], (unsigned long)(p+1)-1))
+                return KDB_BADADDR;
+        if (!kdb_task_state(p, mask))
+                return 0;
+        kdb_printf("Stack traceback for pid %d\n", p->pid);
+        kdb_ps1(p);
+        kdb_show_stack(p, NULL);
+        if (btaprompt) {
+                kdb_getstr(buffer, sizeof(buffer),
+                           "Enter <q> to end, <cr> to continue:");
+                if (buffer[0] == 'q') {
+                        kdb_printf("\n");
+                        return 1;
+                }
+        }
+        touch_nmi_watchdog();
+        return 0;
+}
+
+int
+kdb_bt(int argc, const char **argv)
+{
+        int diag;
+        int argcount = 5;
+        int btaprompt = 1;
+        int nextarg;
+        unsigned long addr;
+        long offset;
+
+        kdbgetintenv("BTARGS", &argcount);      /* Arguments to print */
+        kdbgetintenv("BTAPROMPT", &btaprompt);  /* Prompt after each
+                                                 * proc in bta */
+
+        if (strcmp(argv[0], "bta") == 0) {
+                struct task_struct *g, *p;
+                unsigned long cpu;
+                unsigned long mask = kdb_task_state_string(argc ? argv[1] :
+                                                           NULL);
+                if (argc == 0)
+                        kdb_ps_suppressed();
+                /* Run the active tasks first */
+                for_each_online_cpu(cpu) {
+                        p = kdb_curr_task(cpu);
+                        if (kdb_bt1(p, mask, argcount, btaprompt))
+                                return 0;
+                }
+                /* Now the inactive tasks */
+                kdb_do_each_thread(g, p) {
+                        if (task_curr(p))
+                                continue;
+                        if (kdb_bt1(p, mask, argcount, btaprompt))
+                                return 0;
+                } kdb_while_each_thread(g, p);
+        } else if (strcmp(argv[0], "btp") == 0) {
+                struct task_struct *p;
+                unsigned long pid;
+                if (argc != 1)
+                        return KDB_ARGCOUNT;
+                diag = kdbgetularg((char *)argv[1], &pid);
+                if (diag)
+                        return diag;
+                p = find_task_by_pid_ns(pid, &init_pid_ns);
+                if (p) {
+                        kdb_set_current_task(p);
+                        return kdb_bt1(p, ~0UL, argcount, 0);
+                }
+                kdb_printf("No process with pid == %ld found\n", pid);
+                return 0;
+        } else if (strcmp(argv[0], "btt") == 0) {
+                if (argc != 1)
+                        return KDB_ARGCOUNT;
+                diag = kdbgetularg((char *)argv[1], &addr);
+                if (diag)
+                        return diag;
+                kdb_set_current_task((struct task_struct *)addr);
+                return kdb_bt1((struct task_struct *)addr, ~0UL, argcount, 0);
+        } else if (strcmp(argv[0], "btc") == 0) {
+                unsigned long cpu = ~0;
+                struct task_struct *save_current_task = kdb_current_task;
+                char buf[80];
+                if (argc > 1)
+                        return KDB_ARGCOUNT;
+                if (argc == 1) {
+                        diag = kdbgetularg((char *)argv[1], &cpu);
+                        if (diag)
+                                return diag;
+                }
+                /* Recursive use of kdb_parse, do not use argv after
+                 * this point */
+                argv = NULL;
+                if (cpu != ~0) {
+                        if (cpu >= num_possible_cpus() || !cpu_online(cpu)) {
+                                kdb_printf("no process for cpu %ld\n", cpu);
+                                return 0;
+                        }
+                        sprintf(buf, "btt 0x%p\n", KDB_TSK(cpu));
+                        kdb_parse(buf);
+                        return 0;
+                }
+                kdb_printf("btc: cpu status: ");
+                kdb_parse("cpu\n");
+                for_each_online_cpu(cpu) {
+                        sprintf(buf, "btt 0x%p\n", KDB_TSK(cpu));
+                        kdb_parse(buf);
+                        touch_nmi_watchdog();
+                }
+                kdb_set_current_task(save_current_task);
+                return 0;
+        } else {
+                if (argc) {
+                        nextarg = 1;
+                        diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
+                                             &offset, NULL);
+                        if (diag)
+                                return diag;
+                        kdb_show_stack(kdb_current_task, (void *)addr);
+                        return 0;
+                } else {
+                        return kdb_bt1(kdb_current_task, ~0UL, argcount, 0);
+                }
+        }
+
+        /* NOTREACHED */
+        return 0;
+}
diff --git a/kernel/debug/kdb/kdb_cmds b/kernel/debug/kdb/kdb_cmds
new file mode 100644
index 000000000000..56c88e4db309
--- /dev/null
+++ b/kernel/debug/kdb/kdb_cmds
@@ -0,0 +1,35 @@
+# Initial commands for kdb, alter to suit your needs.
+# These commands are executed in kdb_init() context, no SMP, no
+# processes.  Commands that require process data (including stack or
+# registers) are not reliable this early.  set and bp commands should
+# be safe.  Global breakpoint commands affect each cpu as it is booted.
+
+# Standard debugging information for first level support, just type archkdb
+# or archkdbcpu or archkdbshort at the kdb prompt.
+
+defcmd dumpcommon "" "Common kdb debugging"
+  set BTAPROMPT 0
+  set LINES 10000
+  -summary
+  -cpu
+  -ps
+  -dmesg 600
+  -bt
+endefcmd
+
+defcmd dumpall "" "First line debugging"
+  set BTSYMARG 1
+  set BTARGS 9
+  pid R
+  -dumpcommon
+  -bta
+endefcmd
+
+defcmd dumpcpu "" "Same as dumpall but only tasks on cpus"
+  set BTSYMARG 1
+  set BTARGS 9
+  pid R
+  -dumpcommon
+  -btc
+endefcmd
+
diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c
new file mode 100644
index 000000000000..bf6e8270e957
--- /dev/null
+++ b/kernel/debug/kdb/kdb_debugger.c
@@ -0,0 +1,169 @@
+/*
+ * Created by: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/kdebug.h>
+#include "kdb_private.h"
+#include "../debug_core.h"
+
+/*
+ * KDB interface to KGDB internals
+ */
+get_char_func kdb_poll_funcs[] = {
+        dbg_io_get_char,
+        NULL,
+        NULL,
+        NULL,
+        NULL,
+        NULL,
+};
+EXPORT_SYMBOL_GPL(kdb_poll_funcs);
+
+int kdb_poll_idx = 1;
+EXPORT_SYMBOL_GPL(kdb_poll_idx);
+
+int kdb_stub(struct kgdb_state *ks)
+{
+        int error = 0;
+        kdb_bp_t *bp;
+        unsigned long addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
+        kdb_reason_t reason = KDB_REASON_OOPS;
+        kdb_dbtrap_t db_result = KDB_DB_NOBPT;
+        int i;
+
+        if (KDB_STATE(REENTRY)) {
+                reason = KDB_REASON_SWITCH;
+                KDB_STATE_CLEAR(REENTRY);
+                addr = instruction_pointer(ks->linux_regs);
+        }
+        ks->pass_exception = 0;
+        if (atomic_read(&kgdb_setting_breakpoint))
+                reason = KDB_REASON_KEYBOARD;
+
+        for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) {
+                if ((bp->bp_enabled) && (bp->bp_addr == addr)) {
+                        reason = KDB_REASON_BREAK;
+                        db_result = KDB_DB_BPT;
+                        if (addr != instruction_pointer(ks->linux_regs))
+                                kgdb_arch_set_pc(ks->linux_regs, addr);
+                        break;
+                }
+        }
+        if (reason == KDB_REASON_BREAK || reason == KDB_REASON_SWITCH) {
+                for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) {
+                        if (bp->bp_free)
+                                continue;
+                        if (bp->bp_addr == addr) {
+                                bp->bp_delay = 1;
+                                bp->bp_delayed = 1;
+        /*
+         * SSBPT is set when the kernel debugger must single step a
+         * task in order to re-establish an instruction breakpoint
+         * which uses the instruction replacement mechanism.  It is
+         * cleared by any action that removes the need to single-step
+         * the breakpoint.
+         */
+                                reason = KDB_REASON_BREAK;
+                                db_result = KDB_DB_BPT;
+                                KDB_STATE_SET(SSBPT);
+                                break;
+                        }
+                }
+        }
+
+        if (reason != KDB_REASON_BREAK && ks->ex_vector == 0 &&
+                ks->signo == SIGTRAP) {
+                reason = KDB_REASON_SSTEP;
+                db_result = KDB_DB_BPT;
+        }
+        /* Set initial kdb state variables */
+        KDB_STATE_CLEAR(KGDB_TRANS);
+        kdb_initial_cpu = ks->cpu;
+        kdb_current_task = kgdb_info[ks->cpu].task;
+        kdb_current_regs = kgdb_info[ks->cpu].debuggerinfo;
+        /* Remove any breakpoints as needed by kdb and clear single step */
+        kdb_bp_remove();
+        KDB_STATE_CLEAR(DOING_SS);
+        KDB_STATE_CLEAR(DOING_SSB);
+        KDB_STATE_SET(PAGER);
+        /* zero out any offline cpu data */
+        for_each_present_cpu(i) {
+                if (!cpu_online(i)) {
+                        kgdb_info[i].debuggerinfo = NULL;
+                        kgdb_info[i].task = NULL;
+                }
+        }
+        if (ks->err_code == DIE_OOPS || reason == KDB_REASON_OOPS) {
+                ks->pass_exception = 1;
+                KDB_FLAG_SET(CATASTROPHIC);
+        }
+        kdb_initial_cpu = ks->cpu;
+        if (KDB_STATE(SSBPT) && reason == KDB_REASON_SSTEP) {
+                KDB_STATE_CLEAR(SSBPT);
+                KDB_STATE_CLEAR(DOING_SS);
+        } else {
+                /* Start kdb main loop */
+                error = kdb_main_loop(KDB_REASON_ENTER, reason,
+                                      ks->err_code, db_result, ks->linux_regs);
+        }
+        /*
+         * Upon exit from the kdb main loop setup break points and restart
+         * the system based on the requested continue state
+         */
+        kdb_initial_cpu = -1;
+        kdb_current_task = NULL;
+        kdb_current_regs = NULL;
+        KDB_STATE_CLEAR(PAGER);
+        kdbnearsym_cleanup();
+        if (error == KDB_CMD_KGDB) {
+                if (KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)) {
+        /*
+         * This inteface glue which allows kdb to transition in into
+         * the gdb stub.  In order to do this the '?' or '' gdb serial
+         * packet response is processed here.  And then control is
+         * passed to the gdbstub.
+         */
+                        if (KDB_STATE(DOING_KGDB))
+                                gdbstub_state(ks, "?");
+                        else
+                                gdbstub_state(ks, "");
+                        KDB_STATE_CLEAR(DOING_KGDB);
+                        KDB_STATE_CLEAR(DOING_KGDB2);
+                }
+                return DBG_PASS_EVENT;
+        }
+        kdb_bp_install(ks->linux_regs);
+        dbg_activate_sw_breakpoints();
+        /* Set the exit state to a single step or a continue */
+        if (KDB_STATE(DOING_SS))
+                gdbstub_state(ks, "s");
+        else
+                gdbstub_state(ks, "c");
+
+        KDB_FLAG_CLEAR(CATASTROPHIC);
+
+        /* Invoke arch specific exception handling prior to system resume */
+        kgdb_info[ks->cpu].ret_state = gdbstub_state(ks, "e");
+        if (ks->pass_exception)
+                kgdb_info[ks->cpu].ret_state = 1;
+        if (error == KDB_CMD_CPU) {
+                KDB_STATE_SET(REENTRY);
+                /*
+                 * Force clear the single step bit because kdb emulates this
+                 * differently vs the gdbstub
+                 */
+                kgdb_single_step = 0;
+                dbg_deactivate_sw_breakpoints();
+                return DBG_SWITCH_CPU_EVENT;
+        }
+        return kgdb_info[ks->cpu].ret_state;
+}
+
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
new file mode 100644
index 000000000000..c9b7f4f90bba
--- /dev/null
+++ b/kernel/debug/kdb/kdb_io.c
@@ -0,0 +1,826 @@
+/*
+ * Kernel Debugger Architecture Independent Console I/O handler
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2006 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/kdev_t.h>
+#include <linux/console.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/nmi.h>
+#include <linux/delay.h>
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/kallsyms.h>
+#include "kdb_private.h"
+
+#define CMD_BUFLEN 256
+char kdb_prompt_str[CMD_BUFLEN];
+
+int kdb_trap_printk;
+
+static void kgdb_transition_check(char *buffer)
+{
+        int slen = strlen(buffer);
+        if (strncmp(buffer, "$?#3f", slen) != 0 &&
+            strncmp(buffer, "$qSupported#37", slen) != 0 &&
+            strncmp(buffer, "+$qSupported#37", slen) != 0) {
+                KDB_STATE_SET(KGDB_TRANS);
+                kdb_printf("%s", buffer);
+        }
+}
+
+static int kdb_read_get_key(char *buffer, size_t bufsize)
+{
+#define ESCAPE_UDELAY 1000
+#define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */
+        char escape_data[5];    /* longest vt100 escape sequence is 4 bytes */
+        char *ped = escape_data;
+        int escape_delay = 0;
+        get_char_func *f, *f_escape = NULL;
+        int key;
+
+        for (f = &kdb_poll_funcs[0]; ; ++f) {
+                if (*f == NULL) {
+                        /* Reset NMI watchdog once per poll loop */
+                        touch_nmi_watchdog();
+                        f = &kdb_poll_funcs[0];
+                }
+                if (escape_delay == 2) {
+                        *ped = '\0';
+                        ped = escape_data;
+                        --escape_delay;
+                }
+                if (escape_delay == 1) {
+                        key = *ped++;
+                        if (!*ped)
+                                --escape_delay;
+                        break;
+                }
+                key = (*f)();
+                if (key == -1) {
+                        if (escape_delay) {
+                                udelay(ESCAPE_UDELAY);
+                                --escape_delay;
+                        }
+                        continue;
+                }
+                if (bufsize <= 2) {
+                        if (key == '\r')
+                                key = '\n';
+                        *buffer++ = key;
+                        *buffer = '\0';
+                        return -1;
+                }
+                if (escape_delay == 0 && key == '\e') {
+                        escape_delay = ESCAPE_DELAY;
+                        ped = escape_data;
+                        f_escape = f;
+                }
+                if (escape_delay) {
+                        *ped++ = key;
+                        if (f_escape != f) {
+                                escape_delay = 2;
+                                continue;
+                        }
+                        if (ped - escape_data == 1) {
+                                /* \e */
+                                continue;
+                        } else if (ped - escape_data == 2) {
+                                /* \e<something> */
+                                if (key != '[')
+                                        escape_delay = 2;
+                                continue;
+                        } else if (ped - escape_data == 3) {
+                                /* \e[<something> */
+                                int mapkey = 0;
+                                switch (key) {
+                                case 'A': /* \e[A, up arrow */
+                                        mapkey = 16;
+                                        break;
+                                case 'B': /* \e[B, down arrow */
+                                        mapkey = 14;
+                                        break;
+                                case 'C': /* \e[C, right arrow */
+                                        mapkey = 6;
+                                        break;
+                                case 'D': /* \e[D, left arrow */
+                                        mapkey = 2;
+                                        break;
+                                case '1': /* dropthrough */
+                                case '3': /* dropthrough */
+                                /* \e[<1,3,4>], may be home, del, end */
+                                case '4':
+                                        mapkey = -1;
+                                        break;
+                                }
+                                if (mapkey != -1) {
+                                        if (mapkey > 0) {
+                                                escape_data[0] = mapkey;
+                                                escape_data[1] = '\0';
+                                        }
+                                        escape_delay = 2;
+                                }
+                                continue;
+                        } else if (ped - escape_data == 4) {
+                                /* \e[<1,3,4><something> */
+                                int mapkey = 0;
+                                if (key == '~') {
+                                        switch (escape_data[2]) {
+                                        case '1': /* \e[1~, home */
+                                                mapkey = 1;
+                                                break;
+                                        case '3': /* \e[3~, del */
+                                                mapkey = 4;
+                                                break;
+                                        case '4': /* \e[4~, end */
+                                                mapkey = 5;
+                                                break;
+                                        }
+                                }
+                                if (mapkey > 0) {
+                                        escape_data[0] = mapkey;
+                                        escape_data[1] = '\0';
+                                }
+                                escape_delay = 2;
+                                continue;
+                        }
+                }
+                break;  /* A key to process */
+        }
+        return key;
+}
+
+/*
+ * kdb_read
+ *
+ *      This function reads a string of characters, terminated by
+ *      a newline, or by reaching the end of the supplied buffer,
+ *      from the current kernel debugger console device.
+ * Parameters:
+ *      buffer  - Address of character buffer to receive input characters.
+ *      bufsize - size, in bytes, of the character buffer
+ * Returns:
+ *      Returns a pointer to the buffer containing the received
+ *      character string.  This string will be terminated by a
+ *      newline character.
+ * Locking:
+ *      No locks are required to be held upon entry to this
+ *      function.  It is not reentrant - it relies on the fact
+ *      that while kdb is running on only one "master debug" cpu.
+ * Remarks:
+ *
+ * The buffer size must be >= 2.  A buffer size of 2 means that the caller only
+ * wants a single key.
+ *
+ * An escape key could be the start of a vt100 control sequence such as \e[D
+ * (left arrow) or it could be a character in its own right.  The standard
+ * method for detecting the difference is to wait for 2 seconds to see if there
+ * are any other characters.  kdb is complicated by the lack of a timer service
+ * (interrupts are off), by multiple input sources and by the need to sometimes
+ * return after just one key.  Escape sequence processing has to be done as
+ * states in the polling loop.
+ */
+
+static char *kdb_read(char *buffer, size_t bufsize)
+{
+        char *cp = buffer;
+        char *bufend = buffer+bufsize-2;        /* Reserve space for newline
+                                                 * and null byte */
+        char *lastchar;
+        char *p_tmp;
+        char tmp;
+        static char tmpbuffer[CMD_BUFLEN];
+        int len = strlen(buffer);
+        int len_tmp;
+        int tab = 0;
+        int count;
+        int i;
+        int diag, dtab_count;
+        int key;
+
+
+        diag = kdbgetintenv("DTABCOUNT", &dtab_count);
+        if (diag)
+                dtab_count = 30;
+
+        if (len > 0) {
+                cp += len;
+                if (*(buffer+len-1) == '\n')
+                        cp--;
+        }
+
+        lastchar = cp;
+        *cp = '\0';
+        kdb_printf("%s", buffer);
+poll_again:
+        key = kdb_read_get_key(buffer, bufsize);
+        if (key == -1)
+                return buffer;
+        if (key != 9)
+                tab = 0;
+        switch (key) {
+        case 8: /* backspace */
+                if (cp > buffer) {
+                        if (cp < lastchar) {
+                                memcpy(tmpbuffer, cp, lastchar - cp);
+                                memcpy(cp-1, tmpbuffer, lastchar - cp);
+                        }
+                        *(--lastchar) = '\0';
+                        --cp;
+                        kdb_printf("\b%s \r", cp);
+                        tmp = *cp;
+                        *cp = '\0';
+                        kdb_printf(kdb_prompt_str);
+                        kdb_printf("%s", buffer);
+                        *cp = tmp;
+                }
+                break;
+        case 13: /* enter */
+                *lastchar++ = '\n';
+                *lastchar++ = '\0';
+                kdb_printf("\n");
+                return buffer;
+        case 4: /* Del */
+                if (cp < lastchar) {
+                        memcpy(tmpbuffer, cp+1, lastchar - cp - 1);
+                        memcpy(cp, tmpbuffer, lastchar - cp - 1);
+                        *(--lastchar) = '\0';
+                        kdb_printf("%s \r", cp);
+                        tmp = *cp;
+                        *cp = '\0';
+                        kdb_printf(kdb_prompt_str);
+                        kdb_printf("%s", buffer);
+                        *cp = tmp;
+                }
+                break;
+        case 1: /* Home */
+                if (cp > buffer) {
+                        kdb_printf("\r");
+                        kdb_printf(kdb_prompt_str);
+                        cp = buffer;
+                }
+                break;
+        case 5: /* End */
+                if (cp < lastchar) {
+                        kdb_printf("%s", cp);
+                        cp = lastchar;
+                }
+                break;
+        case 2: /* Left */
+                if (cp > buffer) {
+                        kdb_printf("\b");
+                        --cp;
+                }
+                break;
+        case 14: /* Down */
+                memset(tmpbuffer, ' ',
+                       strlen(kdb_prompt_str) + (lastchar-buffer));
+                *(tmpbuffer+strlen(kdb_prompt_str) +
+                  (lastchar-buffer)) = '\0';
+                kdb_printf("\r%s\r", tmpbuffer);
+                *lastchar = (char)key;
+                *(lastchar+1) = '\0';
+                return lastchar;
+        case 6: /* Right */
+                if (cp < lastchar) {
+                        kdb_printf("%c", *cp);
+                        ++cp;
+                }
+                break;
+        case 16: /* Up */
+                memset(tmpbuffer, ' ',
+                       strlen(kdb_prompt_str) + (lastchar-buffer));
+                *(tmpbuffer+strlen(kdb_prompt_str) +
+                  (lastchar-buffer)) = '\0';
+                kdb_printf("\r%s\r", tmpbuffer);
+                *lastchar = (char)key;
+                *(lastchar+1) = '\0';
+                return lastchar;
+        case 9: /* Tab */
+                if (tab < 2)
+                        ++tab;
+                p_tmp = buffer;
+                while (*p_tmp == ' ')
+                        p_tmp++;
+                if (p_tmp > cp)
+                        break;
+                memcpy(tmpbuffer, p_tmp, cp-p_tmp);
+                *(tmpbuffer + (cp-p_tmp)) = '\0';
+                p_tmp = strrchr(tmpbuffer, ' ');
+                if (p_tmp)
+                        ++p_tmp;
+                else
+                        p_tmp = tmpbuffer;
+                len = strlen(p_tmp);
+                count = kallsyms_symbol_complete(p_tmp,
+                                                 sizeof(tmpbuffer) -
+                                                 (p_tmp - tmpbuffer));
+                if (tab == 2 && count > 0) {
+                        kdb_printf("\n%d symbols are found.", count);
+                        if (count > dtab_count) {
+                                count = dtab_count;
+                                kdb_printf(" But only first %d symbols will"
+                                           " be printed.\nYou can change the"
+                                           " environment variable DTABCOUNT.",
+                                           count);
+                        }
+                        kdb_printf("\n");
+                        for (i = 0; i < count; i++) {
+                                if (kallsyms_symbol_next(p_tmp, i) < 0)
+                                        break;
+                                kdb_printf("%s ", p_tmp);
+                                *(p_tmp + len) = '\0';
+                        }
+                        if (i >= dtab_count)
+                                kdb_printf("...");
+                        kdb_printf("\n");
+                        kdb_printf(kdb_prompt_str);
+                        kdb_printf("%s", buffer);
+                } else if (tab != 2 && count > 0) {
+                        len_tmp = strlen(p_tmp);
+                        strncpy(p_tmp+len_tmp, cp, lastchar-cp+1);
+                        len_tmp = strlen(p_tmp);
+                        strncpy(cp, p_tmp+len, len_tmp-len + 1);
+                        len = len_tmp - len;
+                        kdb_printf("%s", cp);
+                        cp += len;
+                        lastchar += len;
+                }
+                kdb_nextline = 1; /* reset output line number */
+                break;
+        default:
+                if (key >= 32 && lastchar < bufend) {
+                        if (cp < lastchar) {
+                                memcpy(tmpbuffer, cp, lastchar - cp);
+                                memcpy(cp+1, tmpbuffer, lastchar - cp);
+                                *++lastchar = '\0';
+                                *cp = key;
+                                kdb_printf("%s\r", cp);
+                                ++cp;
+                                tmp = *cp;
+                                *cp = '\0';
+                                kdb_printf(kdb_prompt_str);
+                                kdb_printf("%s", buffer);
+                                *cp = tmp;
+                        } else {
+                                *++lastchar = '\0';
+                                *cp++ = key;
+                                /* The kgdb transition check will hide
+                                 * printed characters if we think that
+                                 * kgdb is connecting, until the check
+                                 * fails */
+                                if (!KDB_STATE(KGDB_TRANS))
+                                        kgdb_transition_check(buffer);
+                                else
+                                        kdb_printf("%c", key);
+                        }
+                        /* Special escape to kgdb */
+                        if (lastchar - buffer >= 5 &&
+                            strcmp(lastchar - 5, "$?#3f") == 0) {
+                                strcpy(buffer, "kgdb");
+                                KDB_STATE_SET(DOING_KGDB);
+                                return buffer;
+                        }
+                        if (lastchar - buffer >= 14 &&
+                            strcmp(lastchar - 14, "$qSupported#37") == 0) {
+                                strcpy(buffer, "kgdb");
+                                KDB_STATE_SET(DOING_KGDB2);
+                                return buffer;
+                        }
+                }
+                break;
+        }
+        goto poll_again;
+}
+
+/*
+ * kdb_getstr
+ *
+ *      Print the prompt string and read a command from the
+ *      input device.
+ *
+ * Parameters:
+ *      buffer  Address of buffer to receive command
+ *      bufsize Size of buffer in bytes
+ *      prompt  Pointer to string to use as prompt string
+ * Returns:
+ *      Pointer to command buffer.
+ * Locking:
+ *      None.
+ * Remarks:
+ *      For SMP kernels, the processor number will be
+ *      substituted for %d, %x or %o in the prompt.
+ */
+
+char *kdb_getstr(char *buffer, size_t bufsize, char *prompt)
+{
+        if (prompt && kdb_prompt_str != prompt)
+                strncpy(kdb_prompt_str, prompt, CMD_BUFLEN);
+        kdb_printf(kdb_prompt_str);
+        kdb_nextline = 1;       /* Prompt and input resets line number */
+        return kdb_read(buffer, bufsize);
+}
+
+/*
+ * kdb_input_flush
+ *
+ *      Get rid of any buffered console input.
+ *
+ * Parameters:
+ *      none
+ * Returns:
+ *      nothing
+ * Locking:
+ *      none
+ * Remarks:
+ *      Call this function whenever you want to flush input.  If there is any
+ *      outstanding input, it ignores all characters until there has been no
+ *      data for approximately 1ms.
+ */
+
+static void kdb_input_flush(void)
+{
+        get_char_func *f;
+        int res;
+        int flush_delay = 1;
+        while (flush_delay) {
+                flush_delay--;
+empty:
+                touch_nmi_watchdog();
+                for (f = &kdb_poll_funcs[0]; *f; ++f) {
+                        res = (*f)();
+                        if (res != -1) {
+                                flush_delay = 1;
+                                goto empty;
+                        }
+                }
+                if (flush_delay)
+                        mdelay(1);
+        }
+}
+
+/*
+ * kdb_printf
+ *
+ *      Print a string to the output device(s).
+ *
+ * Parameters:
+ *      printf-like format and optional args.
+ * Returns:
+ *      0
+ * Locking:
+ *      None.
+ * Remarks:
+ *      use 'kdbcons->write()' to avoid polluting 'log_buf' with
+ *      kdb output.
+ *
+ *  If the user is doing a cmd args | grep srch
+ *  then kdb_grepping_flag is set.
+ *  In that case we need to accumulate full lines (ending in \n) before
+ *  searching for the pattern.
+ */
+
+static char kdb_buffer[256];    /* A bit too big to go on stack */
+static char *next_avail = kdb_buffer;
+static int  size_avail;
+static int  suspend_grep;
+
+/*
+ * search arg1 to see if it contains arg2
+ * (kdmain.c provides flags for ^pat and pat$)
+ *
+ * return 1 for found, 0 for not found
+ */
+static int kdb_search_string(char *searched, char *searchfor)
+{
+        char firstchar, *cp;
+        int len1, len2;
+
+        /* not counting the newline at the end of "searched" */
+        len1 = strlen(searched)-1;
+        len2 = strlen(searchfor);
+        if (len1 < len2)
+                return 0;
+        if (kdb_grep_leading && kdb_grep_trailing && len1 != len2)
+                return 0;
+        if (kdb_grep_leading) {
+                if (!strncmp(searched, searchfor, len2))
+                        return 1;
+        } else if (kdb_grep_trailing) {
+                if (!strncmp(searched+len1-len2, searchfor, len2))
+                        return 1;
+        } else {
+                firstchar = *searchfor;
+                cp = searched;
+                while ((cp = strchr(cp, firstchar))) {
+                        if (!strncmp(cp, searchfor, len2))
+                                return 1;
+                        cp++;
+                }
+        }
+        return 0;
+}
+
+int vkdb_printf(const char *fmt, va_list ap)
+{
+        int diag;
+        int linecount;
+        int logging, saved_loglevel = 0;
+        int saved_trap_printk;
+        int got_printf_lock = 0;
+        int retlen = 0;
+        int fnd, len;
+        char *cp, *cp2, *cphold = NULL, replaced_byte = ' ';
+        char *moreprompt = "more> ";
+        struct console *c = console_drivers;
+        static DEFINE_SPINLOCK(kdb_printf_lock);
+        unsigned long uninitialized_var(flags);
+
+        preempt_disable();
+        saved_trap_printk = kdb_trap_printk;
+        kdb_trap_printk = 0;
+
+        /* Serialize kdb_printf if multiple cpus try to write at once.
+         * But if any cpu goes recursive in kdb, just print the output,
+         * even if it is interleaved with any other text.
+         */
+        if (!KDB_STATE(PRINTF_LOCK)) {
+                KDB_STATE_SET(PRINTF_LOCK);
+                spin_lock_irqsave(&kdb_printf_lock, flags);
+                got_printf_lock = 1;
+                atomic_inc(&kdb_event);
+        } else {
+                __acquire(kdb_printf_lock);
+        }
+
+        diag = kdbgetintenv("LINES", &linecount);
+        if (diag || linecount <= 1)
+                linecount = 24;
+
+        diag = kdbgetintenv("LOGGING", &logging);
+        if (diag)
+                logging = 0;
+
+        if (!kdb_grepping_flag || suspend_grep) {
+                /* normally, every vsnprintf starts a new buffer */
+                next_avail = kdb_buffer;
+                size_avail = sizeof(kdb_buffer);
+        }
+        vsnprintf(next_avail, size_avail, fmt, ap);
+
+        /*
+         * If kdb_parse() found that the command was cmd xxx | grep yyy
+         * then kdb_grepping_flag is set, and kdb_grep_string contains yyy
+         *
+         * Accumulate the print data up to a newline before searching it.
+         * (vsnprintf does null-terminate the string that it generates)
+         */
+
+        /* skip the search if prints are temporarily unconditional */
+        if (!suspend_grep && kdb_grepping_flag) {
+                cp = strchr(kdb_buffer, '\n');
+                if (!cp) {
+                        /*
+                         * Special cases that don't end with newlines
+                         * but should be written without one:
+                         *   The "[nn]kdb> " prompt should
+                         *   appear at the front of the buffer.
+                         *
+                         *   The "[nn]more " prompt should also be
+                         *     (MOREPROMPT -> moreprompt)
+                         *   written *   but we print that ourselves,
+                         *   we set the suspend_grep flag to make
+                         *   it unconditional.
+                         *
+                         */
+                        if (next_avail == kdb_buffer) {
+                                /*
+                                 * these should occur after a newline,
+                                 * so they will be at the front of the
+                                 * buffer
+                                 */
+                                cp2 = kdb_buffer;
+                                len = strlen(kdb_prompt_str);
+                                if (!strncmp(cp2, kdb_prompt_str, len)) {
+                                        /*
+                                         * We're about to start a new
+                                         * command, so we can go back
+                                         * to normal mode.
+                                         */
+                                        kdb_grepping_flag = 0;
+                                        goto kdb_printit;
+                                }
+                        }
+                        /* no newline; don't search/write the buffer
+                           until one is there */
+                        len = strlen(kdb_buffer);
+                        next_avail = kdb_buffer + len;
+                        size_avail = sizeof(kdb_buffer) - len;
+                        goto kdb_print_out;
+                }
+
+                /*
+                 * The newline is present; print through it or discard
+                 * it, depending on the results of the search.
+                 */
+                cp++;                /* to byte after the newline */
+                replaced_byte = *cp; /* remember what/where it was */
+                cphold = cp;
+                *cp = '\0';          /* end the string for our search */
+
+                /*
+                 * We now have a newline at the end of the string
+                 * Only continue with this output if it contains the
+                 * search string.
+                 */
+                fnd = kdb_search_string(kdb_buffer, kdb_grep_string);
+                if (!fnd) {
+                        /*
+                         * At this point the complete line at the start
+                         * of kdb_buffer can be discarded, as it does
+                         * not contain what the user is looking for.
+                         * Shift the buffer left.
+                         */
+                        *cphold = replaced_byte;
+                        strcpy(kdb_buffer, cphold);
+                        len = strlen(kdb_buffer);
+                        next_avail = kdb_buffer + len;
+                        size_avail = sizeof(kdb_buffer) - len;
+                        goto kdb_print_out;
+                }
+                /*
+                 * at this point the string is a full line and
+                 * should be printed, up to the null.
+                 */
+        }
+kdb_printit:
+
+        /*
+         * Write to all consoles.
+         */
+        retlen = strlen(kdb_buffer);
+        if (!dbg_kdb_mode && kgdb_connected) {
+                gdbstub_msg_write(kdb_buffer, retlen);
+        } else {
+                if (!dbg_io_ops->is_console) {
+                        len = strlen(kdb_buffer);
+                        cp = kdb_buffer;
+                        while (len--) {
+                                dbg_io_ops->write_char(*cp);
+                                cp++;
+                        }
+                }
+                while (c) {
+                        c->write(c, kdb_buffer, retlen);
+                        touch_nmi_watchdog();
+                        c = c->next;
+                }
+        }
+        if (logging) {
+                saved_loglevel = console_loglevel;
+                console_loglevel = 0;
+                printk(KERN_INFO "%s", kdb_buffer);
+        }
+
+        if (KDB_STATE(PAGER) && strchr(kdb_buffer, '\n'))
+                kdb_nextline++;
+
+        /* check for having reached the LINES number of printed lines */
+        if (kdb_nextline == linecount) {
+                char buf1[16] = "";
+#if defined(CONFIG_SMP)
+                char buf2[32];
+#endif
+
+                /* Watch out for recursion here.  Any routine that calls
+                 * kdb_printf will come back through here.  And kdb_read
+                 * uses kdb_printf to echo on serial consoles ...
+                 */
+                kdb_nextline = 1;       /* In case of recursion */
+
+                /*
+                 * Pause until cr.
+                 */
+                moreprompt = kdbgetenv("MOREPROMPT");
+                if (moreprompt == NULL)
+                        moreprompt = "more> ";
+
+#if defined(CONFIG_SMP)
+                if (strchr(moreprompt, '%')) {
+                        sprintf(buf2, moreprompt, get_cpu());
+                        put_cpu();
+                        moreprompt = buf2;
+                }
+#endif
+
+                kdb_input_flush();
+                c = console_drivers;
+
+                if (!dbg_io_ops->is_console) {
+                        len = strlen(moreprompt);
+                        cp = moreprompt;
+                        while (len--) {
+                                dbg_io_ops->write_char(*cp);
+                                cp++;
+                        }
+                }
+                while (c) {
+                        c->write(c, moreprompt, strlen(moreprompt));
+                        touch_nmi_watchdog();
+                        c = c->next;
+                }
+
+                if (logging)
+                        printk("%s", moreprompt);
+
+                kdb_read(buf1, 2); /* '2' indicates to return
+                                    * immediately after getting one key. */
+                kdb_nextline = 1;       /* Really set output line 1 */
+
+                /* empty and reset the buffer: */
+                kdb_buffer[0] = '\0';
+                next_avail = kdb_buffer;
+                size_avail = sizeof(kdb_buffer);
+                if ((buf1[0] == 'q') || (buf1[0] == 'Q')) {
+                        /* user hit q or Q */
+                        KDB_FLAG_SET(CMD_INTERRUPT); /* command interrupted */
+                        KDB_STATE_CLEAR(PAGER);
+                        /* end of command output; back to normal mode */
+                        kdb_grepping_flag = 0;
+                        kdb_printf("\n");
+                } else if (buf1[0] == ' ') {
+                        kdb_printf("\n");
+                        suspend_grep = 1; /* for this recursion */
+                } else if (buf1[0] == '\n') {
+                        kdb_nextline = linecount - 1;
+                        kdb_printf("\r");
+                        suspend_grep = 1; /* for this recursion */
+                } else if (buf1[0] && buf1[0] != '\n') {
+                        /* user hit something other than enter */
+                        suspend_grep = 1; /* for this recursion */
+                        kdb_printf("\nOnly 'q' or 'Q' are processed at more "
+                                   "prompt, input ignored\n");
+                } else if (kdb_grepping_flag) {
+                        /* user hit enter */
+                        suspend_grep = 1; /* for this recursion */
+                        kdb_printf("\n");
+                }
+                kdb_input_flush();
+        }
+
+        /*
+         * For grep searches, shift the printed string left.
+         *  replaced_byte contains the character that was overwritten with
+         *  the terminating null, and cphold points to the null.
+         * Then adjust the notion of available space in the buffer.
+         */
+        if (kdb_grepping_flag && !suspend_grep) {
+                *cphold = replaced_byte;
+                strcpy(kdb_buffer, cphold);
+                len = strlen(kdb_buffer);
+                next_avail = kdb_buffer + len;
+                size_avail = sizeof(kdb_buffer) - len;
+        }
+
+kdb_print_out:
+        suspend_grep = 0; /* end of what may have been a recursive call */
+        if (logging)
+                console_loglevel = saved_loglevel;
+        if (KDB_STATE(PRINTF_LOCK) && got_printf_lock) {
+                got_printf_lock = 0;
+                spin_unlock_irqrestore(&kdb_printf_lock, flags);
+                KDB_STATE_CLEAR(PRINTF_LOCK);
+                atomic_dec(&kdb_event);
+        } else {
+                __release(kdb_printf_lock);
+        }
+        kdb_trap_printk = saved_trap_printk;
+        preempt_enable();
+        return retlen;
+}
+
+int kdb_printf(const char *fmt, ...)
+{
+        va_list ap;
+        int r;
+
+        va_start(ap, fmt);
+        r = vkdb_printf(fmt, ap);
+        va_end(ap);
+
+        return r;
+}
+
diff --git a/kernel/debug/kdb/kdb_keyboard.c b/kernel/debug/kdb/kdb_keyboard.c
new file mode 100644
index 000000000000..4bca634975c0
--- /dev/null
+++ b/kernel/debug/kdb/kdb_keyboard.c
@@ -0,0 +1,212 @@
+/*
+ * Kernel Debugger Architecture Dependent Console I/O handler
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.
+ *
+ * Copyright (c) 1999-2006 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ */
+
+#include <linux/kdb.h>
+#include <linux/keyboard.h>
+#include <linux/ctype.h>
+#include <linux/module.h>
+#include <linux/io.h>
+
+/* Keyboard Controller Registers on normal PCs. */
+
+#define KBD_STATUS_REG          0x64    /* Status register (R) */
+#define KBD_DATA_REG            0x60    /* Keyboard data register (R/W) */
+
+/* Status Register Bits */
+
+#define KBD_STAT_OBF            0x01    /* Keyboard output buffer full */
+#define KBD_STAT_MOUSE_OBF      0x20    /* Mouse output buffer full */
+
+static int kbd_exists;
+
+/*
+ * Check if the keyboard controller has a keypress for us.
+ * Some parts (Enter Release, LED change) are still blocking polled here,
+ * but hopefully they are all short.
+ */
+int kdb_get_kbd_char(void)
+{
+        int scancode, scanstatus;
+        static int shift_lock;  /* CAPS LOCK state (0-off, 1-on) */
+        static int shift_key;   /* Shift next keypress */
+        static int ctrl_key;
+        u_short keychar;
+
+        if (KDB_FLAG(NO_I8042) || KDB_FLAG(NO_VT_CONSOLE) ||
+            (inb(KBD_STATUS_REG) == 0xff && inb(KBD_DATA_REG) == 0xff)) {
+                kbd_exists = 0;
+                return -1;
+        }
+        kbd_exists = 1;
+
+        if ((inb(KBD_STATUS_REG) & KBD_STAT_OBF) == 0)
+                return -1;
+
+        /*
+         * Fetch the scancode
+         */
+        scancode = inb(KBD_DATA_REG);
+        scanstatus = inb(KBD_STATUS_REG);
+
+        /*
+         * Ignore mouse events.
+         */
+        if (scanstatus & KBD_STAT_MOUSE_OBF)
+                return -1;
+
+        /*
+         * Ignore release, trigger on make
+         * (except for shift keys, where we want to
+         *  keep the shift state so long as the key is
+         *  held down).
+         */
+
+        if (((scancode&0x7f) == 0x2a) || ((scancode&0x7f) == 0x36)) {
+                /*
+                 * Next key may use shift table
+                 */
+                if ((scancode & 0x80) == 0)
+                        shift_key = 1;
+                else
+                        shift_key = 0;
+                return -1;
+        }
+
+        if ((scancode&0x7f) == 0x1d) {
+                /*
+                 * Left ctrl key
+                 */
+                if ((scancode & 0x80) == 0)
+                        ctrl_key = 1;
+                else
+                        ctrl_key = 0;
+                return -1;
+        }
+
+        if ((scancode & 0x80) != 0)
+                return -1;
+
+        scancode &= 0x7f;
+
+        /*
+         * Translate scancode
+         */
+
+        if (scancode == 0x3a) {
+                /*
+                 * Toggle caps lock
+                 */
+                shift_lock ^= 1;
+
+#ifdef  KDB_BLINK_LED
+                kdb_toggleled(0x4);
+#endif
+                return -1;
+        }
+
+        if (scancode == 0x0e) {
+                /*
+                 * Backspace
+                 */
+                return 8;
+        }
+
+        /* Special Key */
+        switch (scancode) {
+        case 0xF: /* Tab */
+                return 9;
+        case 0x53: /* Del */
+                return 4;
+        case 0x47: /* Home */
+                return 1;
+        case 0x4F: /* End */
+                return 5;
+        case 0x4B: /* Left */
+                return 2;
+        case 0x48: /* Up */
+                return 16;
+        case 0x50: /* Down */
+                return 14;
+        case 0x4D: /* Right */
+                return 6;
+        }
+
+        if (scancode == 0xe0)
+                return -1;
+
+        /*
+         * For Japanese 86/106 keyboards
+         *      See comment in drivers/char/pc_keyb.c.
+         *      - Masahiro Adegawa
+         */
+        if (scancode == 0x73)
+                scancode = 0x59;
+        else if (scancode == 0x7d)
+                scancode = 0x7c;
+
+        if (!shift_lock && !shift_key && !ctrl_key) {
+                keychar = plain_map[scancode];
+        } else if ((shift_lock || shift_key) && key_maps[1]) {
+                keychar = key_maps[1][scancode];
+        } else if (ctrl_key && key_maps[4]) {
+                keychar = key_maps[4][scancode];
+        } else {
+                keychar = 0x0020;
+                kdb_printf("Unknown state/scancode (%d)\n", scancode);
+        }
+        keychar &= 0x0fff;
+        if (keychar == '\t')
+                keychar = ' ';
+        switch (KTYP(keychar)) {
+        case KT_LETTER:
+        case KT_LATIN:
+                if (isprint(keychar))
+                        break;          /* printable characters */
+                /* drop through */
+        case KT_SPEC:
+                if (keychar == K_ENTER)
+                        break;
+                /* drop through */
+        default:
+                return -1;      /* ignore unprintables */
+        }
+
+        if ((scancode & 0x7f) == 0x1c) {
+                /*
+                 * enter key.  All done.  Absorb the release scancode.
+                 */
+                while ((inb(KBD_STATUS_REG) & KBD_STAT_OBF) == 0)
+                        ;
+
+                /*
+                 * Fetch the scancode
+                 */
+                scancode = inb(KBD_DATA_REG);
+                scanstatus = inb(KBD_STATUS_REG);
+
+                while (scanstatus & KBD_STAT_MOUSE_OBF) {
+                        scancode = inb(KBD_DATA_REG);
+                        scanstatus = inb(KBD_STATUS_REG);
+                }
+
+                if (scancode != 0x9c) {
+                        /*
+                         * Wasn't an enter-release,  why not?
+                         */
+                        kdb_printf("kdb: expected enter got 0x%x status 0x%x\n",
+                               scancode, scanstatus);
+                }
+
+                return 13;
+        }
+
+        return keychar & 0xff;
+}
+EXPORT_SYMBOL_GPL(kdb_get_kbd_char);
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
new file mode 100644
index 000000000000..b724c791b6d4
--- /dev/null
+++ b/kernel/debug/kdb/kdb_main.c
@@ -0,0 +1,2849 @@
+/*
+ * Kernel Debugger Architecture Independent Main Code
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
+ * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ */
+
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/reboot.h>
+#include <linux/sched.h>
+#include <linux/sysrq.h>
+#include <linux/smp.h>
+#include <linux/utsname.h>
+#include <linux/vmalloc.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/kallsyms.h>
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/notifier.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/nmi.h>
+#include <linux/time.h>
+#include <linux/ptrace.h>
+#include <linux/sysctl.h>
+#include <linux/cpu.h>
+#include <linux/kdebug.h>
+#include <linux/proc_fs.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include "kdb_private.h"
+
+#define GREP_LEN 256
+char kdb_grep_string[GREP_LEN];
+int kdb_grepping_flag;
+EXPORT_SYMBOL(kdb_grepping_flag);
+int kdb_grep_leading;
+int kdb_grep_trailing;
+
+/*
+ * Kernel debugger state flags
+ */
+int kdb_flags;
+atomic_t kdb_event;
+
+/*
+ * kdb_lock protects updates to kdb_initial_cpu.  Used to
+ * single thread processors through the kernel debugger.
+ */
+int kdb_initial_cpu = -1;       /* cpu number that owns kdb */
+int kdb_nextline = 1;
+int kdb_state;                  /* General KDB state */
+
+struct task_struct *kdb_current_task;
+EXPORT_SYMBOL(kdb_current_task);
+struct pt_regs *kdb_current_regs;
+
+const char *kdb_diemsg;
+static int kdb_go_count;
+#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
+static unsigned int kdb_continue_catastrophic =
+        CONFIG_KDB_CONTINUE_CATASTROPHIC;
+#else
+static unsigned int kdb_continue_catastrophic;
+#endif
+
+/* kdb_commands describes the available commands. */
+static kdbtab_t *kdb_commands;
+#define KDB_BASE_CMD_MAX 50
+static int kdb_max_commands = KDB_BASE_CMD_MAX;
+static kdbtab_t kdb_base_commands[50];
+#define for_each_kdbcmd(cmd, num)                                       \
+        for ((cmd) = kdb_base_commands, (num) = 0;                      \
+             num < kdb_max_commands;                                    \
+             num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++, num++)
+
+typedef struct _kdbmsg {
+        int     km_diag;        /* kdb diagnostic */
+        char    *km_msg;        /* Corresponding message text */
+} kdbmsg_t;
+
+#define KDBMSG(msgnum, text) \
+        { KDB_##msgnum, text }
+
+static kdbmsg_t kdbmsgs[] = {
+        KDBMSG(NOTFOUND, "Command Not Found"),
+        KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
+        KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
+               "8 is only allowed on 64 bit systems"),
+        KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
+        KDBMSG(NOTENV, "Cannot find environment variable"),
+        KDBMSG(NOENVVALUE, "Environment variable should have value"),
+        KDBMSG(NOTIMP, "Command not implemented"),
+        KDBMSG(ENVFULL, "Environment full"),
+        KDBMSG(ENVBUFFULL, "Environment buffer full"),
+        KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
+#ifdef CONFIG_CPU_XSCALE
+        KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
+#else
+        KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
+#endif
+        KDBMSG(DUPBPT, "Duplicate breakpoint address"),
+        KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
+        KDBMSG(BADMODE, "Invalid IDMODE"),
+        KDBMSG(BADINT, "Illegal numeric value"),
+        KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
+        KDBMSG(BADREG, "Invalid register name"),
+        KDBMSG(BADCPUNUM, "Invalid cpu number"),
+        KDBMSG(BADLENGTH, "Invalid length field"),
+        KDBMSG(NOBP, "No Breakpoint exists"),
+        KDBMSG(BADADDR, "Invalid address"),
+};
+#undef KDBMSG
+
+static const int __nkdb_err = sizeof(kdbmsgs) / sizeof(kdbmsg_t);
+
+
+/*
+ * Initial environment.   This is all kept static and local to
+ * this file.   We don't want to rely on the memory allocation
+ * mechanisms in the kernel, so we use a very limited allocate-only
+ * heap for new and altered environment variables.  The entire
+ * environment is limited to a fixed number of entries (add more
+ * to __env[] if required) and a fixed amount of heap (add more to
+ * KDB_ENVBUFSIZE if required).
+ */
+
+static char *__env[] = {
+#if defined(CONFIG_SMP)
+ "PROMPT=[%d]kdb> ",
+ "MOREPROMPT=[%d]more> ",
+#else
+ "PROMPT=kdb> ",
+ "MOREPROMPT=more> ",
+#endif
+ "RADIX=16",
+ "MDCOUNT=8",                   /* lines of md output */
+ "BTARGS=9",                    /* 9 possible args in bt */
+ KDB_PLATFORM_ENV,
+ "DTABCOUNT=30",
+ "NOSECT=1",
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+};
+
+static const int __nenv = (sizeof(__env) / sizeof(char *));
+
+struct task_struct *kdb_curr_task(int cpu)
+{
+        struct task_struct *p = curr_task(cpu);
+#ifdef  _TIF_MCA_INIT
+        if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
+                p = krp->p;
+#endif
+        return p;
+}
+
+/*
+ * kdbgetenv - This function will return the character string value of
+ *      an environment variable.
+ * Parameters:
+ *      match   A character string representing an environment variable.
+ * Returns:
+ *      NULL    No environment variable matches 'match'
+ *      char*   Pointer to string value of environment variable.
+ */
+char *kdbgetenv(const char *match)
+{
+        char **ep = __env;
+        int matchlen = strlen(match);
+        int i;
+
+        for (i = 0; i < __nenv; i++) {
+                char *e = *ep++;
+
+                if (!e)
+                        continue;
+
+                if ((strncmp(match, e, matchlen) == 0)
+                 && ((e[matchlen] == '\0')
+                   || (e[matchlen] == '='))) {
+                        char *cp = strchr(e, '=');
+                        return cp ? ++cp : "";
+                }
+        }
+        return NULL;
+}
+
+/*
+ * kdballocenv - This function is used to allocate bytes for
+ *      environment entries.
+ * Parameters:
+ *      match   A character string representing a numeric value
+ * Outputs:
+ *      *value  the unsigned long representation of the env variable 'match'
+ * Returns:
+ *      Zero on success, a kdb diagnostic on failure.
+ * Remarks:
+ *      We use a static environment buffer (envbuffer) to hold the values
+ *      of dynamically generated environment variables (see kdb_set).  Buffer
+ *      space once allocated is never free'd, so over time, the amount of space
+ *      (currently 512 bytes) will be exhausted if env variables are changed
+ *      frequently.
+ */
+static char *kdballocenv(size_t bytes)
+{
+#define KDB_ENVBUFSIZE  512
+        static char envbuffer[KDB_ENVBUFSIZE];
+        static int envbufsize;
+        char *ep = NULL;
+
+        if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
+                ep = &envbuffer[envbufsize];
+                envbufsize += bytes;
+        }
+        return ep;
+}
+
+/*
+ * kdbgetulenv - This function will return the value of an unsigned
+ *      long-valued environment variable.
+ * Parameters:
+ *      match   A character string representing a numeric value
+ * Outputs:
+ *      *value  the unsigned long represntation of the env variable 'match'
+ * Returns:
+ *      Zero on success, a kdb diagnostic on failure.
+ */
+static int kdbgetulenv(const char *match, unsigned long *value)
+{
+        char *ep;
+
+        ep = kdbgetenv(match);
+        if (!ep)
+                return KDB_NOTENV;
+        if (strlen(ep) == 0)
+                return KDB_NOENVVALUE;
+
+        *value = simple_strtoul(ep, NULL, 0);
+
+        return 0;
+}
+
+/*
+ * kdbgetintenv - This function will return the value of an
+ *      integer-valued environment variable.
+ * Parameters:
+ *      match   A character string representing an integer-valued env variable
+ * Outputs:
+ *      *value  the integer representation of the environment variable 'match'
+ * Returns:
+ *      Zero on success, a kdb diagnostic on failure.
+ */
+int kdbgetintenv(const char *match, int *value)
+{
+        unsigned long val;
+        int diag;
+
+        diag = kdbgetulenv(match, &val);
+        if (!diag)
+                *value = (int) val;
+        return diag;
+}
+
+/*
+ * kdbgetularg - This function will convert a numeric string into an
+ *      unsigned long value.
+ * Parameters:
+ *      arg     A character string representing a numeric value
+ * Outputs:
+ *      *value  the unsigned long represntation of arg.
+ * Returns:
+ *      Zero on success, a kdb diagnostic on failure.
+ */
+int kdbgetularg(const char *arg, unsigned long *value)
+{
+        char *endp;
+        unsigned long val;
+
+        val = simple_strtoul(arg, &endp, 0);
+
+        if (endp == arg) {
+                /*
+                 * Try base 16, for us folks too lazy to type the
+                 * leading 0x...
+                 */
+                val = simple_strtoul(arg, &endp, 16);
+                if (endp == arg)
+                        return KDB_BADINT;
+        }
+
+        *value = val;
+
+        return 0;
+}
+
+/*
+ * kdb_set - This function implements the 'set' command.  Alter an
+ *      existing environment variable or create a new one.
+ */
+int kdb_set(int argc, const char **argv)
+{
+        int i;
+        char *ep;
+        size_t varlen, vallen;
+
+        /*
+         * we can be invoked two ways:
+         *   set var=value    argv[1]="var", argv[2]="value"
+         *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
+         * - if the latter, shift 'em down.
+         */
+        if (argc == 3) {
+                argv[2] = argv[3];
+                argc--;
+        }
+
+        if (argc != 2)
+                return KDB_ARGCOUNT;
+
+        /*
+         * Check for internal variables
+         */
+        if (strcmp(argv[1], "KDBDEBUG") == 0) {
+                unsigned int debugflags;
+                char *cp;
+
+                debugflags = simple_strtoul(argv[2], &cp, 0);
+                if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
+                        kdb_printf("kdb: illegal debug flags '%s'\n",
+                                    argv[2]);
+                        return 0;
+                }
+                kdb_flags = (kdb_flags &
+                             ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT))
+                        | (debugflags << KDB_DEBUG_FLAG_SHIFT);
+
+                return 0;
+        }
+
+        /*
+         * Tokenizer squashed the '=' sign.  argv[1] is variable
+         * name, argv[2] = value.
+         */
+        varlen = strlen(argv[1]);
+        vallen = strlen(argv[2]);
+        ep = kdballocenv(varlen + vallen + 2);
+        if (ep == (char *)0)
+                return KDB_ENVBUFFULL;
+
+        sprintf(ep, "%s=%s", argv[1], argv[2]);
+
+        ep[varlen+vallen+1] = '\0';
+
+        for (i = 0; i < __nenv; i++) {
+                if (__env[i]
+                 && ((strncmp(__env[i], argv[1], varlen) == 0)
+                   && ((__env[i][varlen] == '\0')
+                    || (__env[i][varlen] == '=')))) {
+                        __env[i] = ep;
+                        return 0;
+                }
+        }
+
+        /*
+         * Wasn't existing variable.  Fit into slot.
+         */
+        for (i = 0; i < __nenv-1; i++) {
+                if (__env[i] == (char *)0) {
+                        __env[i] = ep;
+                        return 0;
+                }
+        }
+
+        return KDB_ENVFULL;
+}
+
+static int kdb_check_regs(void)
+{
+        if (!kdb_current_regs) {
+                kdb_printf("No current kdb registers."
+                           "  You may need to select another task\n");
+                return KDB_BADREG;
+        }
+        return 0;
+}
+
+/*
+ * kdbgetaddrarg - This function is responsible for parsing an
+ *      address-expression and returning the value of the expression,
+ *      symbol name, and offset to the caller.
+ *
+ *      The argument may consist of a numeric value (decimal or
+ *      hexidecimal), a symbol name, a register name (preceeded by the
+ *      percent sign), an environment variable with a numeric value
+ *      (preceeded by a dollar sign) or a simple arithmetic expression
+ *      consisting of a symbol name, +/-, and a numeric constant value
+ *      (offset).
+ * Parameters:
+ *      argc    - count of arguments in argv
+ *      argv    - argument vector
+ *      *nextarg - index to next unparsed argument in argv[]
+ *      regs    - Register state at time of KDB entry
+ * Outputs:
+ *      *value  - receives the value of the address-expression
+ *      *offset - receives the offset specified, if any
+ *      *name   - receives the symbol name, if any
+ *      *nextarg - index to next unparsed argument in argv[]
+ * Returns:
+ *      zero is returned on success, a kdb diagnostic code is
+ *      returned on error.
+ */
+int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
+                  unsigned long *value,  long *offset,
+                  char **name)
+{
+        unsigned long addr;
+        unsigned long off = 0;
+        int positive;
+        int diag;
+        int found = 0;
+        char *symname;
+        char symbol = '\0';
+        char *cp;
+        kdb_symtab_t symtab;
+
+        /*
+         * Process arguments which follow the following syntax:
+         *
+         *  symbol | numeric-address [+/- numeric-offset]
+         *  %register
+         *  $environment-variable
+         */
+
+        if (*nextarg > argc)
+                return KDB_ARGCOUNT;
+
+        symname = (char *)argv[*nextarg];
+
+        /*
+         * If there is no whitespace between the symbol
+         * or address and the '+' or '-' symbols, we
+         * remember the character and replace it with a
+         * null so the symbol/value can be properly parsed
+         */
+        cp = strpbrk(symname, "+-");
+        if (cp != NULL) {
+                symbol = *cp;
+                *cp++ = '\0';
+        }
+
+        if (symname[0] == '$') {
+                diag = kdbgetulenv(&symname[1], &addr);
+                if (diag)
+                        return diag;
+        } else if (symname[0] == '%') {
+                diag = kdb_check_regs();
+                if (diag)
+                        return diag;
+                /* Implement register values with % at a later time as it is
+                 * arch optional.
+                 */
+                return KDB_NOTIMP;
+        } else {
+                found = kdbgetsymval(symname, &symtab);
+                if (found) {
+                        addr = symtab.sym_start;
+                } else {
+                        diag = kdbgetularg(argv[*nextarg], &addr);
+                        if (diag)
+                                return diag;
+                }
+        }
+
+        if (!found)
+                found = kdbnearsym(addr, &symtab);
+
+        (*nextarg)++;
+
+        if (name)
+                *name = symname;
+        if (value)
+                *value = addr;
+        if (offset && name && *name)
+                *offset = addr - symtab.sym_start;
+
+        if ((*nextarg > argc)
+         && (symbol == '\0'))
+                return 0;
+
+        /*
+         * check for +/- and offset
+         */
+
+        if (symbol == '\0') {
+                if ((argv[*nextarg][0] != '+')
+                 && (argv[*nextarg][0] != '-')) {
+                        /*
+                         * Not our argument.  Return.
+                         */
+                        return 0;
+                } else {
+                        positive = (argv[*nextarg][0] == '+');
+                        (*nextarg)++;
+                }
+        } else
+                positive = (symbol == '+');
+
+        /*
+         * Now there must be an offset!
+         */
+        if ((*nextarg > argc)
+         && (symbol == '\0')) {
+                return KDB_INVADDRFMT;
+        }
+
+        if (!symbol) {
+                cp = (char *)argv[*nextarg];
+                (*nextarg)++;
+        }
+
+        diag = kdbgetularg(cp, &off);
+        if (diag)
+                return diag;
+
+        if (!positive)
+                off = -off;
+
+        if (offset)
+                *offset += off;
+
+        if (value)
+                *value += off;
+
+        return 0;
+}
+
+static void kdb_cmderror(int diag)
+{
+        int i;
+
+        if (diag >= 0) {
+                kdb_printf("no error detected (diagnostic is %d)\n", diag);
+                return;
+        }
+
+        for (i = 0; i < __nkdb_err; i++) {
+                if (kdbmsgs[i].km_diag == diag) {
+                        kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
+                        return;
+                }
+        }
+
+        kdb_printf("Unknown diag %d\n", -diag);
+}
+
+/*
+ * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
+ *      command which defines one command as a set of other commands,
+ *      terminated by endefcmd.  kdb_defcmd processes the initial
+ *      'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
+ *      the following commands until 'endefcmd'.
+ * Inputs:
+ *      argc    argument count
+ *      argv    argument vector
+ * Returns:
+ *      zero for success, a kdb diagnostic if error
+ */
+struct defcmd_set {
+        int count;
+        int usable;
+        char *name;
+        char *usage;
+        char *help;
+        char **command;
+};
+static struct defcmd_set *defcmd_set;
+static int defcmd_set_count;
+static int defcmd_in_progress;
+
+/* Forward references */
+static int kdb_exec_defcmd(int argc, const char **argv);
+
+static int kdb_defcmd2(const char *cmdstr, const char *argv0)
+{
+        struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
+        char **save_command = s->command;
+        if (strcmp(argv0, "endefcmd") == 0) {
+                defcmd_in_progress = 0;
+                if (!s->count)
+                        s->usable = 0;
+                if (s->usable)
+                        kdb_register(s->name, kdb_exec_defcmd,
+                                     s->usage, s->help, 0);
+                return 0;
+        }
+        if (!s->usable)
+                return KDB_NOTIMP;
+        s->command = kmalloc((s->count + 1) * sizeof(*(s->command)), GFP_KDB);
+        if (!s->command) {
+                kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
+                           cmdstr);
+                s->usable = 0;
+                return KDB_NOTIMP;
+        }
+        memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
+        s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
+        kfree(save_command);
+        return 0;
+}
+
+static int kdb_defcmd(int argc, const char **argv)
+{
+        struct defcmd_set *save_defcmd_set = defcmd_set, *s;
+        if (defcmd_in_progress) {
+                kdb_printf("kdb: nested defcmd detected, assuming missing "
+                           "endefcmd\n");
+                kdb_defcmd2("endefcmd", "endefcmd");
+        }
+        if (argc == 0) {
+                int i;
+                for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
+                        kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
+                                   s->usage, s->help);
+                        for (i = 0; i < s->count; ++i)
+                                kdb_printf("%s", s->command[i]);
+                        kdb_printf("endefcmd\n");
+                }
+                return 0;
+        }
+        if (argc != 3)
+                return KDB_ARGCOUNT;
+        defcmd_set = kmalloc((defcmd_set_count + 1) * sizeof(*defcmd_set),
+                             GFP_KDB);
+        if (!defcmd_set) {
+                kdb_printf("Could not allocate new defcmd_set entry for %s\n",
+                           argv[1]);
+                defcmd_set = save_defcmd_set;
+                return KDB_NOTIMP;
+        }
+        memcpy(defcmd_set, save_defcmd_set,
+               defcmd_set_count * sizeof(*defcmd_set));
+        kfree(save_defcmd_set);
+        s = defcmd_set + defcmd_set_count;
+        memset(s, 0, sizeof(*s));
+        s->usable = 1;
+        s->name = kdb_strdup(argv[1], GFP_KDB);
+        s->usage = kdb_strdup(argv[2], GFP_KDB);
+        s->help = kdb_strdup(argv[3], GFP_KDB);
+        if (s->usage[0] == '"') {
+                strcpy(s->usage, s->usage+1);
+                s->usage[strlen(s->usage)-1] = '\0';
+        }
+        if (s->help[0] == '"') {
+                strcpy(s->help, s->help+1);
+                s->help[strlen(s->help)-1] = '\0';
+        }
+        ++defcmd_set_count;
+        defcmd_in_progress = 1;
+        return 0;
+}
+
+/*
+ * kdb_exec_defcmd - Execute the set of commands associated with this
+ *      defcmd name.
+ * Inputs:
+ *      argc    argument count
+ *      argv    argument vector
+ * Returns:
+ *      zero for success, a kdb diagnostic if error
+ */
+static int kdb_exec_defcmd(int argc, const char **argv)
+{
+        int i, ret;
+        struct defcmd_set *s;
+        if (argc != 0)
+                return KDB_ARGCOUNT;
+        for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
+                if (strcmp(s->name, argv[0]) == 0)
+                        break;
+        }
+        if (i == defcmd_set_count) {
+                kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
+                           argv[0]);
+                return KDB_NOTIMP;
+        }
+        for (i = 0; i < s->count; ++i) {
+                /* Recursive use of kdb_parse, do not use argv after
+                 * this point */
+                argv = NULL;
+                kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
+                ret = kdb_parse(s->command[i]);
+                if (ret)
+                        return ret;
+        }
+        return 0;
+}
+
+/* Command history */
+#define KDB_CMD_HISTORY_COUNT   32
+#define CMD_BUFLEN              200     /* kdb_printf: max printline
+                                         * size == 256 */
+static unsigned int cmd_head, cmd_tail;
+static unsigned int cmdptr;
+static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
+static char cmd_cur[CMD_BUFLEN];
+
+/*
+ * The "str" argument may point to something like  | grep xyz
+ */
+static void parse_grep(const char *str)
+{
+        int     len;
+        char    *cp = (char *)str, *cp2;
+
+        /* sanity check: we should have been called with the \ first */
+        if (*cp != '|')
+                return;
+        cp++;
+        while (isspace(*cp))
+                cp++;
+        if (strncmp(cp, "grep ", 5)) {
+                kdb_printf("invalid 'pipe', see grephelp\n");
+                return;
+        }
+        cp += 5;
+        while (isspace(*cp))
+                cp++;
+        cp2 = strchr(cp, '\n');
+        if (cp2)
+                *cp2 = '\0'; /* remove the trailing newline */
+        len = strlen(cp);
+        if (len == 0) {
+                kdb_printf("invalid 'pipe', see grephelp\n");
+                return;
+        }
+        /* now cp points to a nonzero length search string */
+        if (*cp == '"') {
+                /* allow it be "x y z" by removing the "'s - there must
+                   be two of them */
+                cp++;
+                cp2 = strchr(cp, '"');
+                if (!cp2) {
+                        kdb_printf("invalid quoted string, see grephelp\n");
+                        return;
+                }
+                *cp2 = '\0'; /* end the string where the 2nd " was */
+        }
+        kdb_grep_leading = 0;
+        if (*cp == '^') {
+                kdb_grep_leading = 1;
+                cp++;
+        }
+        len = strlen(cp);
+        kdb_grep_trailing = 0;
+        if (*(cp+len-1) == '$') {
+                kdb_grep_trailing = 1;
+                *(cp+len-1) = '\0';
+        }
+        len = strlen(cp);
+        if (!len)
+                return;
+        if (len >= GREP_LEN) {
+                kdb_printf("search string too long\n");
+                return;
+        }
+        strcpy(kdb_grep_string, cp);
+        kdb_grepping_flag++;
+        return;
+}
+
+/*
+ * kdb_parse - Parse the command line, search the command table for a
+ *      matching command and invoke the command function.  This
+ *      function may be called recursively, if it is, the second call
+ *      will overwrite argv and cbuf.  It is the caller's
+ *      responsibility to save their argv if they recursively call
+ *      kdb_parse().
+ * Parameters:
+ *      cmdstr  The input command line to be parsed.
+ *      regs    The registers at the time kdb was entered.
+ * Returns:
+ *      Zero for success, a kdb diagnostic if failure.
+ * Remarks:
+ *      Limited to 20 tokens.
+ *
+ *      Real rudimentary tokenization. Basically only whitespace
+ *      is considered a token delimeter (but special consideration
+ *      is taken of the '=' sign as used by the 'set' command).
+ *
+ *      The algorithm used to tokenize the input string relies on
+ *      there being at least one whitespace (or otherwise useless)
+ *      character between tokens as the character immediately following
+ *      the token is altered in-place to a null-byte to terminate the
+ *      token string.
+ */
+
+#define MAXARGC 20
+
+int kdb_parse(const char *cmdstr)
+{
+        static char *argv[MAXARGC];
+        static int argc;
+        static char cbuf[CMD_BUFLEN+2];
+        char *cp;
+        char *cpp, quoted;
+        kdbtab_t *tp;
+        int i, escaped, ignore_errors = 0, check_grep;
+
+        /*
+         * First tokenize the command string.
+         */
+        cp = (char *)cmdstr;
+        kdb_grepping_flag = check_grep = 0;
+
+        if (KDB_FLAG(CMD_INTERRUPT)) {
+                /* Previous command was interrupted, newline must not
+                 * repeat the command */
+                KDB_FLAG_CLEAR(CMD_INTERRUPT);
+                KDB_STATE_SET(PAGER);
+                argc = 0;       /* no repeat */
+        }
+
+        if (*cp != '\n' && *cp != '\0') {
+                argc = 0;
+                cpp = cbuf;
+                while (*cp) {
+                        /* skip whitespace */
+                        while (isspace(*cp))
+                                cp++;
+                        if ((*cp == '\0') || (*cp == '\n') ||
+                            (*cp == '#' && !defcmd_in_progress))
+                                break;
+                        /* special case: check for | grep pattern */
+                        if (*cp == '|') {
+                                check_grep++;
+                                break;
+                        }
+                        if (cpp >= cbuf + CMD_BUFLEN) {
+                                kdb_printf("kdb_parse: command buffer "
+                                           "overflow, command ignored\n%s\n",
+                                           cmdstr);
+                                return KDB_NOTFOUND;
+                        }
+                        if (argc >= MAXARGC - 1) {
+                                kdb_printf("kdb_parse: too many arguments, "
+                                           "command ignored\n%s\n", cmdstr);
+                                return KDB_NOTFOUND;
+                        }
+                        argv[argc++] = cpp;
+                        escaped = 0;
+                        quoted = '\0';
+                        /* Copy to next unquoted and unescaped
+                         * whitespace or '=' */
+                        while (*cp && *cp != '\n' &&
+                               (escaped || quoted || !isspace(*cp))) {
+                                if (cpp >= cbuf + CMD_BUFLEN)
+                                        break;
+                                if (escaped) {
+                                        escaped = 0;
+                                        *cpp++ = *cp++;
+                                        continue;
+                                }
+                                if (*cp == '\\') {
+                                        escaped = 1;
+                                        ++cp;
+                                        continue;
+                                }
+                                if (*cp == quoted)
+                                        quoted = '\0';
+                                else if (*cp == '\'' || *cp == '"')
+                                        quoted = *cp;
+                                *cpp = *cp++;
+                                if (*cpp == '=' && !quoted)
+                                        break;
+                                ++cpp;
+                        }
+                        *cpp++ = '\0';  /* Squash a ws or '=' character */
+                }
+        }
+        if (!argc)
+                return 0;
+        if (check_grep)
+                parse_grep(cp);
+        if (defcmd_in_progress) {
+                int result = kdb_defcmd2(cmdstr, argv[0]);
+                if (!defcmd_in_progress) {
+                        argc = 0;       /* avoid repeat on endefcmd */
+                        *(argv[0]) = '\0';
+                }
+                return result;
+        }
+        if (argv[0][0] == '-' && argv[0][1] &&
+            (argv[0][1] < '0' || argv[0][1] > '9')) {
+                ignore_errors = 1;
+                ++argv[0];
+        }
+
+        for_each_kdbcmd(tp, i) {
+                if (tp->cmd_name) {
+                        /*
+                         * If this command is allowed to be abbreviated,
+                         * check to see if this is it.
+                         */
+
+                        if (tp->cmd_minlen
+                         && (strlen(argv[0]) <= tp->cmd_minlen)) {
+                                if (strncmp(argv[0],
+                                            tp->cmd_name,
+                                            tp->cmd_minlen) == 0) {
+                                        break;
+                                }
+                        }
+
+                        if (strcmp(argv[0], tp->cmd_name) == 0)
+                                break;
+                }
+        }
+
+        /*
+         * If we don't find a command by this name, see if the first
+         * few characters of this match any of the known commands.
+         * e.g., md1c20 should match md.
+         */
+        if (i == kdb_max_commands) {
+                for_each_kdbcmd(tp, i) {
+                        if (tp->cmd_name) {
+                                if (strncmp(argv[0],
+                                            tp->cmd_name,
+                                            strlen(tp->cmd_name)) == 0) {
+                                        break;
+                                }
+                        }
+                }
+        }
+
+        if (i < kdb_max_commands) {
+                int result;
+                KDB_STATE_SET(CMD);
+                result = (*tp->cmd_func)(argc-1, (const char **)argv);
+                if (result && ignore_errors && result > KDB_CMD_GO)
+                        result = 0;
+                KDB_STATE_CLEAR(CMD);
+                switch (tp->cmd_repeat) {
+                case KDB_REPEAT_NONE:
+                        argc = 0;
+                        if (argv[0])
+                                *(argv[0]) = '\0';
+                        break;
+                case KDB_REPEAT_NO_ARGS:
+                        argc = 1;
+                        if (argv[1])
+                                *(argv[1]) = '\0';
+                        break;
+                case KDB_REPEAT_WITH_ARGS:
+                        break;
+                }
+                return result;
+        }
+
+        /*
+         * If the input with which we were presented does not
+         * map to an existing command, attempt to parse it as an
+         * address argument and display the result.   Useful for
+         * obtaining the address of a variable, or the nearest symbol
+         * to an address contained in a register.
+         */
+        {
+                unsigned long value;
+                char *name = NULL;
+                long offset;
+                int nextarg = 0;
+
+                if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
+                                  &value, &offset, &name)) {
+                        return KDB_NOTFOUND;
+                }
+
+                kdb_printf("%s = ", argv[0]);
+                kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
+                kdb_printf("\n");
+                return 0;
+        }
+}
+
+
+static int handle_ctrl_cmd(char *cmd)
+{
+#define CTRL_P  16
+#define CTRL_N  14
+
+        /* initial situation */
+        if (cmd_head == cmd_tail)
+                return 0;
+        switch (*cmd) {
+        case CTRL_P:
+                if (cmdptr != cmd_tail)
+                        cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
+                strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
+                return 1;
+        case CTRL_N:
+                if (cmdptr != cmd_head)
+                        cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
+                strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
+                return 1;
+        }
+        return 0;
+}
+
+/*
+ * kdb_reboot - This function implements the 'reboot' command.  Reboot
+ *      the system immediately, or loop for ever on failure.
+ */
+static int kdb_reboot(int argc, const char **argv)
+{
+        emergency_restart();
+        kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
+        while (1)
+                cpu_relax();
+        /* NOTREACHED */
+        return 0;
+}
+
+static void kdb_dumpregs(struct pt_regs *regs)
+{
+        int old_lvl = console_loglevel;
+        console_loglevel = 15;
+        kdb_trap_printk++;
+        show_regs(regs);
+        kdb_trap_printk--;
+        kdb_printf("\n");
+        console_loglevel = old_lvl;
+}
+
+void kdb_set_current_task(struct task_struct *p)
+{
+        kdb_current_task = p;
+
+        if (kdb_task_has_cpu(p)) {
+                kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
+                return;
+        }
+        kdb_current_regs = NULL;
+}
+
+/*
+ * kdb_local - The main code for kdb.  This routine is invoked on a
+ *      specific processor, it is not global.  The main kdb() routine
+ *      ensures that only one processor at a time is in this routine.
+ *      This code is called with the real reason code on the first
+ *      entry to a kdb session, thereafter it is called with reason
+ *      SWITCH, even if the user goes back to the original cpu.
+ * Inputs:
+ *      reason          The reason KDB was invoked
+ *      error           The hardware-defined error code
+ *      regs            The exception frame at time of fault/breakpoint.
+ *      db_result       Result code from the break or debug point.
+ * Returns:
+ *      0       KDB was invoked for an event which it wasn't responsible
+ *      1       KDB handled the event for which it was invoked.
+ *      KDB_CMD_GO      User typed 'go'.
+ *      KDB_CMD_CPU     User switched to another cpu.
+ *      KDB_CMD_SS      Single step.
+ *      KDB_CMD_SSB     Single step until branch.
+ */
+static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
+                     kdb_dbtrap_t db_result)
+{
+        char *cmdbuf;
+        int diag;
+        struct task_struct *kdb_current =
+                kdb_curr_task(raw_smp_processor_id());
+
+        KDB_DEBUG_STATE("kdb_local 1", reason);
+        kdb_go_count = 0;
+        if (reason == KDB_REASON_DEBUG) {
+                /* special case below */
+        } else {
+                kdb_printf("\nEntering kdb (current=0x%p, pid %d) ",
+                           kdb_current, kdb_current->pid);
+#if defined(CONFIG_SMP)
+                kdb_printf("on processor %d ", raw_smp_processor_id());
+#endif
+        }
+
+        switch (reason) {
+        case KDB_REASON_DEBUG:
+        {
+                /*
+                 * If re-entering kdb after a single step
+                 * command, don't print the message.
+                 */
+                switch (db_result) {
+                case KDB_DB_BPT:
+                        kdb_printf("\nEntering kdb (0x%p, pid %d) ",
+                                   kdb_current, kdb_current->pid);
+#if defined(CONFIG_SMP)
+                        kdb_printf("on processor %d ", raw_smp_processor_id());
+#endif
+                        kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
+                                   instruction_pointer(regs));
+                        break;
+                case KDB_DB_SSB:
+                        /*
+                         * In the midst of ssb command. Just return.
+                         */
+                        KDB_DEBUG_STATE("kdb_local 3", reason);
+                        return KDB_CMD_SSB;     /* Continue with SSB command */
+
+                        break;
+                case KDB_DB_SS:
+                        break;
+                case KDB_DB_SSBPT:
+                        KDB_DEBUG_STATE("kdb_local 4", reason);
+                        return 1;       /* kdba_db_trap did the work */
+                default:
+                        kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
+                                   db_result);
+                        break;
+                }
+
+        }
+                break;
+        case KDB_REASON_ENTER:
+                if (KDB_STATE(KEYBOARD))
+                        kdb_printf("due to Keyboard Entry\n");
+                else
+                        kdb_printf("due to KDB_ENTER()\n");
+                break;
+        case KDB_REASON_KEYBOARD:
+                KDB_STATE_SET(KEYBOARD);
+                kdb_printf("due to Keyboard Entry\n");
+                break;
+        case KDB_REASON_ENTER_SLAVE:
+                /* drop through, slaves only get released via cpu switch */
+        case KDB_REASON_SWITCH:
+                kdb_printf("due to cpu switch\n");
+                break;
+        case KDB_REASON_OOPS:
+                kdb_printf("Oops: %s\n", kdb_diemsg);
+                kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
+                           instruction_pointer(regs));
+                kdb_dumpregs(regs);
+                break;
+        case KDB_REASON_NMI:
+                kdb_printf("due to NonMaskable Interrupt @ "
+                           kdb_machreg_fmt "\n",
+                           instruction_pointer(regs));
+                kdb_dumpregs(regs);
+                break;
+        case KDB_REASON_SSTEP:
+        case KDB_REASON_BREAK:
+                kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
+                           reason == KDB_REASON_BREAK ?
+                           "Breakpoint" : "SS trap", instruction_pointer(regs));
+                /*
+                 * Determine if this breakpoint is one that we
+                 * are interested in.
+                 */
+                if (db_result != KDB_DB_BPT) {
+                        kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
+                                   db_result);
+                        KDB_DEBUG_STATE("kdb_local 6", reason);
+                        return 0;       /* Not for us, dismiss it */
+                }
+                break;
+        case KDB_REASON_RECURSE:
+                kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
+                           instruction_pointer(regs));
+                break;
+        default:
+                kdb_printf("kdb: unexpected reason code: %d\n", reason);
+                KDB_DEBUG_STATE("kdb_local 8", reason);
+                return 0;       /* Not for us, dismiss it */
+        }
+
+        while (1) {
+                /*
+                 * Initialize pager context.
+                 */
+                kdb_nextline = 1;
+                KDB_STATE_CLEAR(SUPPRESS);
+
+                cmdbuf = cmd_cur;
+                *cmdbuf = '\0';
+                *(cmd_hist[cmd_head]) = '\0';
+
+                if (KDB_FLAG(ONLY_DO_DUMP)) {
+                        /* kdb is off but a catastrophic error requires a dump.
+                         * Take the dump and reboot.
+                         * Turn on logging so the kdb output appears in the log
+                         * buffer in the dump.
+                         */
+                        const char *setargs[] = { "set", "LOGGING", "1" };
+                        kdb_set(2, setargs);
+                        kdb_reboot(0, NULL);
+                        /*NOTREACHED*/
+                }
+
+do_full_getstr:
+#if defined(CONFIG_SMP)
+                snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
+                         raw_smp_processor_id());
+#else
+                snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"));
+#endif
+                if (defcmd_in_progress)
+                        strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
+
+                /*
+                 * Fetch command from keyboard
+                 */
+                cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
+                if (*cmdbuf != '\n') {
+                        if (*cmdbuf < 32) {
+                                if (cmdptr == cmd_head) {
+                                        strncpy(cmd_hist[cmd_head], cmd_cur,
+                                                CMD_BUFLEN);
+                                        *(cmd_hist[cmd_head] +
+                                          strlen(cmd_hist[cmd_head])-1) = '\0';
+                                }
+                                if (!handle_ctrl_cmd(cmdbuf))
+                                        *(cmd_cur+strlen(cmd_cur)-1) = '\0';
+                                cmdbuf = cmd_cur;
+                                goto do_full_getstr;
+                        } else {
+                                strncpy(cmd_hist[cmd_head], cmd_cur,
+                                        CMD_BUFLEN);
+                        }
+
+                        cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
+                        if (cmd_head == cmd_tail)
+                                cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
+                }
+
+                cmdptr = cmd_head;
+                diag = kdb_parse(cmdbuf);
+                if (diag == KDB_NOTFOUND) {
+                        kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
+                        diag = 0;
+                }
+                if (diag == KDB_CMD_GO
+                 || diag == KDB_CMD_CPU
+                 || diag == KDB_CMD_SS
+                 || diag == KDB_CMD_SSB
+                 || diag == KDB_CMD_KGDB)
+                        break;
+
+                if (diag)
+                        kdb_cmderror(diag);
+        }
+        KDB_DEBUG_STATE("kdb_local 9", diag);
+        return diag;
+}
+
+
+/*
+ * kdb_print_state - Print the state data for the current processor
+ *      for debugging.
+ * Inputs:
+ *      text            Identifies the debug point
+ *      value           Any integer value to be printed, e.g. reason code.
+ */
+void kdb_print_state(const char *text, int value)
+{
+        kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
+                   text, raw_smp_processor_id(), value, kdb_initial_cpu,
+                   kdb_state);
+}
+
+/*
+ * kdb_main_loop - After initial setup and assignment of the
+ *      controlling cpu, all cpus are in this loop.  One cpu is in
+ *      control and will issue the kdb prompt, the others will spin
+ *      until 'go' or cpu switch.
+ *
+ *      To get a consistent view of the kernel stacks for all
+ *      processes, this routine is invoked from the main kdb code via
+ *      an architecture specific routine.  kdba_main_loop is
+ *      responsible for making the kernel stacks consistent for all
+ *      processes, there should be no difference between a blocked
+ *      process and a running process as far as kdb is concerned.
+ * Inputs:
+ *      reason          The reason KDB was invoked
+ *      error           The hardware-defined error code
+ *      reason2         kdb's current reason code.
+ *                      Initially error but can change
+ *                      acording to kdb state.
+ *      db_result       Result code from break or debug point.
+ *      regs            The exception frame at time of fault/breakpoint.
+ *                      should always be valid.
+ * Returns:
+ *      0       KDB was invoked for an event which it wasn't responsible
+ *      1       KDB handled the event for which it was invoked.
+ */
+int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
+              kdb_dbtrap_t db_result, struct pt_regs *regs)
+{
+        int result = 1;
+        /* Stay in kdb() until 'go', 'ss[b]' or an error */
+        while (1) {
+                /*
+                 * All processors except the one that is in control
+                 * will spin here.
+                 */
+                KDB_DEBUG_STATE("kdb_main_loop 1", reason);
+                while (KDB_STATE(HOLD_CPU)) {
+                        /* state KDB is turned off by kdb_cpu to see if the
+                         * other cpus are still live, each cpu in this loop
+                         * turns it back on.
+                         */
+                        if (!KDB_STATE(KDB))
+                                KDB_STATE_SET(KDB);
+                }
+
+                KDB_STATE_CLEAR(SUPPRESS);
+                KDB_DEBUG_STATE("kdb_main_loop 2", reason);
+                if (KDB_STATE(LEAVING))
+                        break;  /* Another cpu said 'go' */
+                /* Still using kdb, this processor is in control */
+                result = kdb_local(reason2, error, regs, db_result);
+                KDB_DEBUG_STATE("kdb_main_loop 3", result);
+
+                if (result == KDB_CMD_CPU)
+                        break;
+
+                if (result == KDB_CMD_SS) {
+                        KDB_STATE_SET(DOING_SS);
+                        break;
+                }
+
+                if (result == KDB_CMD_SSB) {
+                        KDB_STATE_SET(DOING_SS);
+                        KDB_STATE_SET(DOING_SSB);
+                        break;
+                }
+
+                if (result == KDB_CMD_KGDB) {
+                        if (!(KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)))
+                                kdb_printf("Entering please attach debugger "
+                                           "or use $D#44+ or $3#33\n");
+                        break;
+                }
+                if (result && result != 1 && result != KDB_CMD_GO)
+                        kdb_printf("\nUnexpected kdb_local return code %d\n",
+                                   result);
+                KDB_DEBUG_STATE("kdb_main_loop 4", reason);
+                break;
+        }
+        if (KDB_STATE(DOING_SS))
+                KDB_STATE_CLEAR(SSBPT);
+
+        return result;
+}
+
+/*
+ * kdb_mdr - This function implements the guts of the 'mdr', memory
+ * read command.
+ *      mdr  <addr arg>,<byte count>
+ * Inputs:
+ *      addr    Start address
+ *      count   Number of bytes
+ * Returns:
+ *      Always 0.  Any errors are detected and printed by kdb_getarea.
+ */
+static int kdb_mdr(unsigned long addr, unsigned int count)
+{
+        unsigned char c;
+        while (count--) {
+                if (kdb_getarea(c, addr))
+                        return 0;
+                kdb_printf("%02x", c);
+                addr++;
+        }
+        kdb_printf("\n");
+        return 0;
+}
+
+/*
+ * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
+ *      'md8' 'mdr' and 'mds' commands.
+ *
+ *      md|mds  [<addr arg> [<line count> [<radix>]]]
+ *      mdWcN   [<addr arg> [<line count> [<radix>]]]
+ *              where W = is the width (1, 2, 4 or 8) and N is the count.
+ *              for eg., md1c20 reads 20 bytes, 1 at a time.
+ *      mdr  <addr arg>,<byte count>
+ */
+static void kdb_md_line(const char *fmtstr, unsigned long addr,
+                        int symbolic, int nosect, int bytesperword,
+                        int num, int repeat, int phys)
+{
+        /* print just one line of data */
+        kdb_symtab_t symtab;
+        char cbuf[32];
+        char *c = cbuf;
+        int i;
+        unsigned long word;
+
+        memset(cbuf, '\0', sizeof(cbuf));
+        if (phys)
+                kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
+        else
+                kdb_printf(kdb_machreg_fmt0 " ", addr);
+
+        for (i = 0; i < num && repeat--; i++) {
+                if (phys) {
+                        if (kdb_getphysword(&word, addr, bytesperword))
+                                break;
+                } else if (kdb_getword(&word, addr, bytesperword))
+                        break;
+                kdb_printf(fmtstr, word);
+                if (symbolic)
+                        kdbnearsym(word, &symtab);
+                else
+                        memset(&symtab, 0, sizeof(symtab));
+                if (symtab.sym_name) {
+                        kdb_symbol_print(word, &symtab, 0);
+                        if (!nosect) {
+                                kdb_printf("\n");
+                                kdb_printf("                       %s %s "
+                                           kdb_machreg_fmt " "
+                                           kdb_machreg_fmt " "
+                                           kdb_machreg_fmt, symtab.mod_name,
+                                           symtab.sec_name, symtab.sec_start,
+                                           symtab.sym_start, symtab.sym_end);
+                        }
+                        addr += bytesperword;
+                } else {
+                        union {
+                                u64 word;
+                                unsigned char c[8];
+                        } wc;
+                        unsigned char *cp;
+#ifdef  __BIG_ENDIAN
+                        cp = wc.c + 8 - bytesperword;
+#else
+                        cp = wc.c;
+#endif
+                        wc.word = word;
+#define printable_char(c) \
+        ({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
+                        switch (bytesperword) {
+                        case 8:
+                                *c++ = printable_char(*cp++);
+                                *c++ = printable_char(*cp++);
+                                *c++ = printable_char(*cp++);
+                                *c++ = printable_char(*cp++);
+                                addr += 4;
+                        case 4:
+                                *c++ = printable_char(*cp++);
+                                *c++ = printable_char(*cp++);
+                                addr += 2;
+                        case 2:
+                                *c++ = printable_char(*cp++);
+                                addr++;
+                        case 1:
+                                *c++ = printable_char(*cp++);
+                                addr++;
+                                break;
+                        }
+#undef printable_char
+                }
+        }
+        kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
+                   " ", cbuf);
+}
+
+static int kdb_md(int argc, const char **argv)
+{
+        static unsigned long last_addr;
+        static int last_radix, last_bytesperword, last_repeat;
+        int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
+        int nosect = 0;
+        char fmtchar, fmtstr[64];
+        unsigned long addr;
+        unsigned long word;
+        long offset = 0;
+        int symbolic = 0;
+        int valid = 0;
+        int phys = 0;
+
+        kdbgetintenv("MDCOUNT", &mdcount);
+        kdbgetintenv("RADIX", &radix);
+        kdbgetintenv("BYTESPERWORD", &bytesperword);
+
+        /* Assume 'md <addr>' and start with environment values */
+        repeat = mdcount * 16 / bytesperword;
+
+        if (strcmp(argv[0], "mdr") == 0) {
+                if (argc != 2)
+                        return KDB_ARGCOUNT;
+                valid = 1;
+        } else if (isdigit(argv[0][2])) {
+                bytesperword = (int)(argv[0][2] - '0');
+                if (bytesperword == 0) {
+                        bytesperword = last_bytesperword;
+                        if (bytesperword == 0)
+                                bytesperword = 4;
+                }
+                last_bytesperword = bytesperword;
+                repeat = mdcount * 16 / bytesperword;
+                if (!argv[0][3])
+                        valid = 1;
+                else if (argv[0][3] == 'c' && argv[0][4]) {
+                        char *p;
+                        repeat = simple_strtoul(argv[0] + 4, &p, 10);
+                        mdcount = ((repeat * bytesperword) + 15) / 16;
+                        valid = !*p;
+                }
+                last_repeat = repeat;
+        } else if (strcmp(argv[0], "md") == 0)
+                valid = 1;
+        else if (strcmp(argv[0], "mds") == 0)
+                valid = 1;
+        else if (strcmp(argv[0], "mdp") == 0) {
+                phys = valid = 1;
+        }
+        if (!valid)
+                return KDB_NOTFOUND;
+
+        if (argc == 0) {
+                if (last_addr == 0)
+                        return KDB_ARGCOUNT;
+                addr = last_addr;
+                radix = last_radix;
+                bytesperword = last_bytesperword;
+                repeat = last_repeat;
+                mdcount = ((repeat * bytesperword) + 15) / 16;
+        }
+
+        if (argc) {
+                unsigned long val;
+                int diag, nextarg = 1;
+                diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
+                                     &offset, NULL);
+                if (diag)
+                        return diag;
+                if (argc > nextarg+2)
+                        return KDB_ARGCOUNT;
+
+                if (argc >= nextarg) {
+                        diag = kdbgetularg(argv[nextarg], &val);
+                        if (!diag) {
+                                mdcount = (int) val;
+                                repeat = mdcount * 16 / bytesperword;
+                        }
+                }
+                if (argc >= nextarg+1) {
+                        diag = kdbgetularg(argv[nextarg+1], &val);
+                        if (!diag)
+                                radix = (int) val;
+                }
+        }
+
+        if (strcmp(argv[0], "mdr") == 0)
+                return kdb_mdr(addr, mdcount);
+
+        switch (radix) {
+        case 10:
+                fmtchar = 'd';
+                break;
+        case 16:
+                fmtchar = 'x';
+                break;
+        case 8:
+                fmtchar = 'o';
+                break;
+        default:
+                return KDB_BADRADIX;
+        }
+
+        last_radix = radix;
+
+        if (bytesperword > KDB_WORD_SIZE)
+                return KDB_BADWIDTH;
+
+        switch (bytesperword) {
+        case 8:
+                sprintf(fmtstr, "%%16.16l%c ", fmtchar);
+                break;
+        case 4:
+                sprintf(fmtstr, "%%8.8l%c ", fmtchar);
+                break;
+        case 2:
+                sprintf(fmtstr, "%%4.4l%c ", fmtchar);
+                break;
+        case 1:
+                sprintf(fmtstr, "%%2.2l%c ", fmtchar);
+                break;
+        default:
+                return KDB_BADWIDTH;
+        }
+
+        last_repeat = repeat;
+        last_bytesperword = bytesperword;
+
+        if (strcmp(argv[0], "mds") == 0) {
+                symbolic = 1;
+                /* Do not save these changes as last_*, they are temporary mds
+                 * overrides.
+                 */
+                bytesperword = KDB_WORD_SIZE;
+                repeat = mdcount;
+                kdbgetintenv("NOSECT", &nosect);
+        }
+
+        /* Round address down modulo BYTESPERWORD */
+
+        addr &= ~(bytesperword-1);
+
+        while (repeat > 0) {
+                unsigned long a;
+                int n, z, num = (symbolic ? 1 : (16 / bytesperword));
+
+                if (KDB_FLAG(CMD_INTERRUPT))
+                        return 0;
+                for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
+                        if (phys) {
+                                if (kdb_getphysword(&word, a, bytesperword)
+                                                || word)
+                                        break;
+                        } else if (kdb_getword(&word, a, bytesperword) || word)
+                                break;
+                }
+                n = min(num, repeat);
+                kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
+                            num, repeat, phys);
+                addr += bytesperword * n;
+                repeat -= n;
+                z = (z + num - 1) / num;
+                if (z > 2) {
+                        int s = num * (z-2);
+                        kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
+                                   " zero suppressed\n",
+                                addr, addr + bytesperword * s - 1);
+                        addr += bytesperword * s;
+                        repeat -= s;
+                }
+        }
+        last_addr = addr;
+
+        return 0;
+}
+
+/*
+ * kdb_mm - This function implements the 'mm' command.
+ *      mm address-expression new-value
+ * Remarks:
+ *      mm works on machine words, mmW works on bytes.
+ */
+static int kdb_mm(int argc, const char **argv)
+{
+        int diag;
+        unsigned long addr;
+        long offset = 0;
+        unsigned long contents;
+        int nextarg;
+        int width;
+
+        if (argv[0][2] && !isdigit(argv[0][2]))
+                return KDB_NOTFOUND;
+
+        if (argc < 2)
+                return KDB_ARGCOUNT;
+
+        nextarg = 1;
+        diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
+        if (diag)
+                return diag;
+
+        if (nextarg > argc)
+                return KDB_ARGCOUNT;
+        diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
+        if (diag)
+                return diag;
+
+        if (nextarg != argc + 1)
+                return KDB_ARGCOUNT;
+
+        width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
+        diag = kdb_putword(addr, contents, width);
+        if (diag)
+                return diag;
+
+        kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
+
+        return 0;
+}
+
+/*
+ * kdb_go - This function implements the 'go' command.
+ *      go [address-expression]
+ */
+static int kdb_go(int argc, const char **argv)
+{
+        unsigned long addr;
+        int diag;
+        int nextarg;
+        long offset;
+
+        if (argc == 1) {
+                if (raw_smp_processor_id() != kdb_initial_cpu) {
+                        kdb_printf("go <address> must be issued from the "
+                                   "initial cpu, do cpu %d first\n",
+                                   kdb_initial_cpu);
+                        return KDB_ARGCOUNT;
+                }
+                nextarg = 1;
+                diag = kdbgetaddrarg(argc, argv, &nextarg,
+                                     &addr, &offset, NULL);
+                if (diag)
+                        return diag;
+        } else if (argc) {
+                return KDB_ARGCOUNT;
+        }
+
+        diag = KDB_CMD_GO;
+        if (KDB_FLAG(CATASTROPHIC)) {
+                kdb_printf("Catastrophic error detected\n");
+                kdb_printf("kdb_continue_catastrophic=%d, ",
+                        kdb_continue_catastrophic);
+                if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
+                        kdb_printf("type go a second time if you really want "
+                                   "to continue\n");
+                        return 0;
+                }
+                if (kdb_continue_catastrophic == 2) {
+                        kdb_printf("forcing reboot\n");
+                        kdb_reboot(0, NULL);
+                }
+                kdb_printf("attempting to continue\n");
+        }
+        return diag;
+}
+
+/*
+ * kdb_rd - This function implements the 'rd' command.
+ */
+static int kdb_rd(int argc, const char **argv)
+{
+        int diag = kdb_check_regs();
+        if (diag)
+                return diag;
+
+        kdb_dumpregs(kdb_current_regs);
+        return 0;
+}
+
+/*
+ * kdb_rm - This function implements the 'rm' (register modify)  command.
+ *      rm register-name new-contents
+ * Remarks:
+ *      Currently doesn't allow modification of control or
+ *      debug registers.
+ */
+static int kdb_rm(int argc, const char **argv)
+{
+        int diag;
+        int ind = 0;
+        unsigned long contents;
+
+        if (argc != 2)
+                return KDB_ARGCOUNT;
+        /*
+         * Allow presence or absence of leading '%' symbol.
+         */
+        if (argv[1][0] == '%')
+                ind = 1;
+
+        diag = kdbgetularg(argv[2], &contents);
+        if (diag)
+                return diag;
+
+        diag = kdb_check_regs();
+        if (diag)
+                return diag;
+        kdb_printf("ERROR: Register set currently not implemented\n");
+        return 0;
+}
+
+#if defined(CONFIG_MAGIC_SYSRQ)
+/*
+ * kdb_sr - This function implements the 'sr' (SYSRQ key) command
+ *      which interfaces to the soi-disant MAGIC SYSRQ functionality.
+ *              sr <magic-sysrq-code>
+ */
+static int kdb_sr(int argc, const char **argv)
+{
+        if (argc != 1)
+                return KDB_ARGCOUNT;
+        sysrq_toggle_support(1);
+        kdb_trap_printk++;
+        handle_sysrq(*argv[1], NULL);
+        kdb_trap_printk--;
+
+        return 0;
+}
+#endif  /* CONFIG_MAGIC_SYSRQ */
+
+/*
+ * kdb_ef - This function implements the 'regs' (display exception
+ *      frame) command.  This command takes an address and expects to
+ *      find an exception frame at that address, formats and prints
+ *      it.
+ *              regs address-expression
+ * Remarks:
+ *      Not done yet.
+ */
+static int kdb_ef(int argc, const char **argv)
+{
+        int diag;
+        unsigned long addr;
+        long offset;
+        int nextarg;
+
+        if (argc != 1)
+                return KDB_ARGCOUNT;
+
+        nextarg = 1;
+        diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
+        if (diag)
+                return diag;
+        show_regs((struct pt_regs *)addr);
+        return 0;
+}
+
+#if defined(CONFIG_MODULES)
+/* modules using other modules */
+struct module_use {
+        struct list_head list;
+        struct module *module_which_uses;
+};
+
+/*
+ * kdb_lsmod - This function implements the 'lsmod' command.  Lists
+ *      currently loaded kernel modules.
+ *      Mostly taken from userland lsmod.
+ */
+static int kdb_lsmod(int argc, const char **argv)
+{
+        struct module *mod;
+
+        if (argc != 0)
+                return KDB_ARGCOUNT;
+
+        kdb_printf("Module                  Size  modstruct     Used by\n");
+        list_for_each_entry(mod, kdb_modules, list) {
+
+                kdb_printf("%-20s%8u  0x%p ", mod->name,
+                           mod->core_size, (void *)mod);
+#ifdef CONFIG_MODULE_UNLOAD
+                kdb_printf("%4d ", module_refcount(mod));
+#endif
+                if (mod->state == MODULE_STATE_GOING)
+                        kdb_printf(" (Unloading)");
+                else if (mod->state == MODULE_STATE_COMING)
+                        kdb_printf(" (Loading)");
+                else
+                        kdb_printf(" (Live)");
+
+#ifdef CONFIG_MODULE_UNLOAD
+                {
+                        struct module_use *use;
+                        kdb_printf(" [ ");
+                        list_for_each_entry(use, &mod->modules_which_use_me,
+                                            list)
+                                kdb_printf("%s ", use->module_which_uses->name);
+                        kdb_printf("]\n");
+                }
+#endif
+        }
+
+        return 0;
+}
+
+#endif  /* CONFIG_MODULES */
+
+/*
+ * kdb_env - This function implements the 'env' command.  Display the
+ *      current environment variables.
+ */
+
+static int kdb_env(int argc, const char **argv)
+{
+        int i;
+
+        for (i = 0; i < __nenv; i++) {
+                if (__env[i])
+                        kdb_printf("%s\n", __env[i]);
+        }
+
+        if (KDB_DEBUG(MASK))
+                kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
+
+        return 0;
+}
+
+#ifdef CONFIG_PRINTK
+/*
+ * kdb_dmesg - This function implements the 'dmesg' command to display
+ *      the contents of the syslog buffer.
+ *              dmesg [lines] [adjust]
+ */
+static int kdb_dmesg(int argc, const char **argv)
+{
+        char *syslog_data[4], *start, *end, c = '\0', *p;
+        int diag, logging, logsize, lines = 0, adjust = 0, n;
+
+        if (argc > 2)
+                return KDB_ARGCOUNT;
+        if (argc) {
+                char *cp;
+                lines = simple_strtol(argv[1], &cp, 0);
+                if (*cp)
+                        lines = 0;
+                if (argc > 1) {
+                        adjust = simple_strtoul(argv[2], &cp, 0);
+                        if (*cp || adjust < 0)
+                                adjust = 0;
+                }
+        }
+
+        /* disable LOGGING if set */
+        diag = kdbgetintenv("LOGGING", &logging);
+        if (!diag && logging) {
+                const char *setargs[] = { "set", "LOGGING", "0" };
+                kdb_set(2, setargs);
+        }
+
+        /* syslog_data[0,1] physical start, end+1.  syslog_data[2,3]
+         * logical start, end+1. */
+        kdb_syslog_data(syslog_data);
+        if (syslog_data[2] == syslog_data[3])
+                return 0;
+        logsize = syslog_data[1] - syslog_data[0];
+        start = syslog_data[2];
+        end = syslog_data[3];
+#define KDB_WRAP(p) (((p - syslog_data[0]) % logsize) + syslog_data[0])
+        for (n = 0, p = start; p < end; ++p) {
+                c = *KDB_WRAP(p);
+                if (c == '\n')
+                        ++n;
+        }
+        if (c != '\n')
+                ++n;
+        if (lines < 0) {
+                if (adjust >= n)
+                        kdb_printf("buffer only contains %d lines, nothing "
+                                   "printed\n", n);
+                else if (adjust - lines >= n)
+                        kdb_printf("buffer only contains %d lines, last %d "
+                                   "lines printed\n", n, n - adjust);
+                if (adjust) {
+                        for (; start < end && adjust; ++start) {
+                                if (*KDB_WRAP(start) == '\n')
+                                        --adjust;
+                        }
+                        if (start < end)
+                                ++start;
+                }
+                for (p = start; p < end && lines; ++p) {
+                        if (*KDB_WRAP(p) == '\n')
+                                ++lines;
+                }
+                end = p;
+        } else if (lines > 0) {
+                int skip = n - (adjust + lines);
+                if (adjust >= n) {
+                        kdb_printf("buffer only contains %d lines, "
+                                   "nothing printed\n", n);
+                        skip = n;
+                } else if (skip < 0) {
+                        lines += skip;
+                        skip = 0;
+                        kdb_printf("buffer only contains %d lines, first "
+                                   "%d lines printed\n", n, lines);
+                }
+                for (; start < end && skip; ++start) {
+                        if (*KDB_WRAP(start) == '\n')
+                                --skip;
+                }
+                for (p = start; p < end && lines; ++p) {
+                        if (*KDB_WRAP(p) == '\n')
+                                --lines;
+                }
+                end = p;
+        }
+        /* Do a line at a time (max 200 chars) to reduce protocol overhead */
+        c = '\n';
+        while (start != end) {
+                char buf[201];
+                p = buf;
+                if (KDB_FLAG(CMD_INTERRUPT))
+                        return 0;
+                while (start < end && (c = *KDB_WRAP(start)) &&
+                       (p - buf) < sizeof(buf)-1) {
+                        ++start;
+                        *p++ = c;
+                        if (c == '\n')
+                                break;
+                }
+                *p = '\0';
+                kdb_printf("%s", buf);
+        }
+        if (c != '\n')
+                kdb_printf("\n");
+
+        return 0;
+}
+#endif /* CONFIG_PRINTK */
+/*
+ * kdb_cpu - This function implements the 'cpu' command.
+ *      cpu     [<cpunum>]
+ * Returns:
+ *      KDB_CMD_CPU for success, a kdb diagnostic if error
+ */
+static void kdb_cpu_status(void)
+{
+        int i, start_cpu, first_print = 1;
+        char state, prev_state = '?';
+
+        kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
+        kdb_printf("Available cpus: ");
+        for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
+                if (!cpu_online(i)) {
+                        state = 'F';    /* cpu is offline */
+                } else {
+                        state = ' ';    /* cpu is responding to kdb */
+                        if (kdb_task_state_char(KDB_TSK(i)) == 'I')
+                                state = 'I';    /* idle task */
+                }
+                if (state != prev_state) {
+                        if (prev_state != '?') {
+                                if (!first_print)
+                                        kdb_printf(", ");
+                                first_print = 0;
+                                kdb_printf("%d", start_cpu);
+                                if (start_cpu < i-1)
+                                        kdb_printf("-%d", i-1);
+                                if (prev_state != ' ')
+                                        kdb_printf("(%c)", prev_state);
+                        }
+                        prev_state = state;
+                        start_cpu = i;
+                }
+        }
+        /* print the trailing cpus, ignoring them if they are all offline */
+        if (prev_state != 'F') {
+                if (!first_print)
+                        kdb_printf(", ");
+                kdb_printf("%d", start_cpu);
+                if (start_cpu < i-1)
+                        kdb_printf("-%d", i-1);
+                if (prev_state != ' ')
+                        kdb_printf("(%c)", prev_state);
+        }
+        kdb_printf("\n");
+}
+
+static int kdb_cpu(int argc, const char **argv)
+{
+        unsigned long cpunum;
+        int diag;
+
+        if (argc == 0) {
+                kdb_cpu_status();
+                return 0;
+        }
+
+        if (argc != 1)
+                return KDB_ARGCOUNT;
+
+        diag = kdbgetularg(argv[1], &cpunum);
+        if (diag)
+                return diag;
+
+        /*
+         * Validate cpunum
+         */
+        if ((cpunum > NR_CPUS) || !cpu_online(cpunum))
+                return KDB_BADCPUNUM;
+
+        dbg_switch_cpu = cpunum;
+
+        /*
+         * Switch to other cpu
+         */
+        return KDB_CMD_CPU;
+}
+
+/* The user may not realize that ps/bta with no parameters does not print idle
+ * or sleeping system daemon processes, so tell them how many were suppressed.
+ */
+void kdb_ps_suppressed(void)
+{
+        int idle = 0, daemon = 0;
+        unsigned long mask_I = kdb_task_state_string("I"),
+                      mask_M = kdb_task_state_string("M");
+        unsigned long cpu;
+        const struct task_struct *p, *g;
+        for_each_online_cpu(cpu) {
+                p = kdb_curr_task(cpu);
+                if (kdb_task_state(p, mask_I))
+                        ++idle;
+        }
+        kdb_do_each_thread(g, p) {
+                if (kdb_task_state(p, mask_M))
+                        ++daemon;
+        } kdb_while_each_thread(g, p);
+        if (idle || daemon) {
+                if (idle)
+                        kdb_printf("%d idle process%s (state I)%s\n",
+                                   idle, idle == 1 ? "" : "es",
+                                   daemon ? " and " : "");
+                if (daemon)
+                        kdb_printf("%d sleeping system daemon (state M) "
+                                   "process%s", daemon,
+                                   daemon == 1 ? "" : "es");
+                kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
+        }
+}
+
+/*
+ * kdb_ps - This function implements the 'ps' command which shows a
+ *      list of the active processes.
+ *              ps [DRSTCZEUIMA]   All processes, optionally filtered by state
+ */
+void kdb_ps1(const struct task_struct *p)
+{
+        int cpu;
+        unsigned long tmp;
+
+        if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
+                return;
+
+        cpu = kdb_process_cpu(p);
+        kdb_printf("0x%p %8d %8d  %d %4d   %c  0x%p %c%s\n",
+                   (void *)p, p->pid, p->parent->pid,
+                   kdb_task_has_cpu(p), kdb_process_cpu(p),
+                   kdb_task_state_char(p),
+                   (void *)(&p->thread),
+                   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
+                   p->comm);
+        if (kdb_task_has_cpu(p)) {
+                if (!KDB_TSK(cpu)) {
+                        kdb_printf("  Error: no saved data for this cpu\n");
+                } else {
+                        if (KDB_TSK(cpu) != p)
+                                kdb_printf("  Error: does not match running "
+                                   "process table (0x%p)\n", KDB_TSK(cpu));
+                }
+        }
+}
+
+static int kdb_ps(int argc, const char **argv)
+{
+        struct task_struct *g, *p;
+        unsigned long mask, cpu;
+
+        if (argc == 0)
+                kdb_ps_suppressed();
+        kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
+                (int)(2*sizeof(void *))+2, "Task Addr",
+                (int)(2*sizeof(void *))+2, "Thread");
+        mask = kdb_task_state_string(argc ? argv[1] : NULL);
+        /* Run the active tasks first */
+        for_each_online_cpu(cpu) {
+                if (KDB_FLAG(CMD_INTERRUPT))
+                        return 0;
+                p = kdb_curr_task(cpu);
+                if (kdb_task_state(p, mask))
+                        kdb_ps1(p);
+        }
+        kdb_printf("\n");
+        /* Now the real tasks */
+        kdb_do_each_thread(g, p) {
+                if (KDB_FLAG(CMD_INTERRUPT))
+                        return 0;
+                if (kdb_task_state(p, mask))
+                        kdb_ps1(p);
+        } kdb_while_each_thread(g, p);
+
+        return 0;
+}
+
+/*
+ * kdb_pid - This function implements the 'pid' command which switches
+ *      the currently active process.
+ *              pid [<pid> | R]
+ */
+static int kdb_pid(int argc, const char **argv)
+{
+        struct task_struct *p;
+        unsigned long val;
+        int diag;
+
+        if (argc > 1)
+                return KDB_ARGCOUNT;
+
+        if (argc) {
+                if (strcmp(argv[1], "R") == 0) {
+                        p = KDB_TSK(kdb_initial_cpu);
+                } else {
+                        diag = kdbgetularg(argv[1], &val);
+                        if (diag)
+                                return KDB_BADINT;
+
+                        p = find_task_by_pid_ns((pid_t)val,     &init_pid_ns);
+                        if (!p) {
+                                kdb_printf("No task with pid=%d\n", (pid_t)val);
+                                return 0;
+                        }
+                }
+                kdb_set_current_task(p);
+        }
+        kdb_printf("KDB current process is %s(pid=%d)\n",
+                   kdb_current_task->comm,
+                   kdb_current_task->pid);
+
+        return 0;
+}
+
+/*
+ * kdb_ll - This function implements the 'll' command which follows a
+ *      linked list and executes an arbitrary command for each
+ *      element.
+ */
+static int kdb_ll(int argc, const char **argv)
+{
+        int diag;
+        unsigned long addr;
+        long offset = 0;
+        unsigned long va;
+        unsigned long linkoffset;
+        int nextarg;
+        const char *command;
+
+        if (argc != 3)
+                return KDB_ARGCOUNT;
+
+        nextarg = 1;
+        diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
+        if (diag)
+                return diag;
+
+        diag = kdbgetularg(argv[2], &linkoffset);
+        if (diag)
+                return diag;
+
+        /*
+         * Using the starting address as
+         * the first element in the list, and assuming that
+         * the list ends with a null pointer.
+         */
+
+        va = addr;
+        command = kdb_strdup(argv[3], GFP_KDB);
+        if (!command) {
+                kdb_printf("%s: cannot duplicate command\n", __func__);
+                return 0;
+        }
+        /* Recursive use of kdb_parse, do not use argv after this point */
+        argv = NULL;
+
+        while (va) {
+                char buf[80];
+
+                sprintf(buf, "%s " kdb_machreg_fmt "\n", command, va);
+                diag = kdb_parse(buf);
+                if (diag)
+                        return diag;
+
+                addr = va + linkoffset;
+                if (kdb_getword(&va, addr, sizeof(va)))
+                        return 0;
+        }
+        kfree(command);
+
+        return 0;
+}
+
+static int kdb_kgdb(int argc, const char **argv)
+{
+        return KDB_CMD_KGDB;
+}
+
+/*
+ * kdb_help - This function implements the 'help' and '?' commands.
+ */
+static int kdb_help(int argc, const char **argv)
+{
+        kdbtab_t *kt;
+        int i;
+
+        kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
+        kdb_printf("-----------------------------"
+                   "-----------------------------\n");
+        for_each_kdbcmd(kt, i) {
+                if (kt->cmd_name)
+                        kdb_printf("%-15.15s %-20.20s %s\n", kt->cmd_name,
+                                   kt->cmd_usage, kt->cmd_help);
+                if (KDB_FLAG(CMD_INTERRUPT))
+                        return 0;
+        }
+        return 0;
+}
+
+/*
+ * kdb_kill - This function implements the 'kill' commands.
+ */
+static int kdb_kill(int argc, const char **argv)
+{
+        long sig, pid;
+        char *endp;
+        struct task_struct *p;
+        struct siginfo info;
+
+        if (argc != 2)
+                return KDB_ARGCOUNT;
+
+        sig = simple_strtol(argv[1], &endp, 0);
+        if (*endp)
+                return KDB_BADINT;
+        if (sig >= 0) {
+                kdb_printf("Invalid signal parameter.<-signal>\n");
+                return 0;
+        }
+        sig = -sig;
+
+        pid = simple_strtol(argv[2], &endp, 0);
+        if (*endp)
+                return KDB_BADINT;
+        if (pid <= 0) {
+                kdb_printf("Process ID must be large than 0.\n");
+                return 0;
+        }
+
+        /* Find the process. */
+        p = find_task_by_pid_ns(pid, &init_pid_ns);
+        if (!p) {
+                kdb_printf("The specified process isn't found.\n");
+                return 0;
+        }
+        p = p->group_leader;
+        info.si_signo = sig;
+        info.si_errno = 0;
+        info.si_code = SI_USER;
+        info.si_pid = pid;  /* same capabilities as process being signalled */
+        info.si_uid = 0;    /* kdb has root authority */
+        kdb_send_sig_info(p, &info);
+        return 0;
+}
+
+struct kdb_tm {
+        int tm_sec;     /* seconds */
+        int tm_min;     /* minutes */
+        int tm_hour;    /* hours */
+        int tm_mday;    /* day of the month */
+        int tm_mon;     /* month */
+        int tm_year;    /* year */
+};
+
+static void kdb_gmtime(struct timespec *tv, struct kdb_tm *tm)
+{
+        /* This will work from 1970-2099, 2100 is not a leap year */
+        static int mon_day[] = { 31, 29, 31, 30, 31, 30, 31,
+                                 31, 30, 31, 30, 31 };
+        memset(tm, 0, sizeof(*tm));
+        tm->tm_sec  = tv->tv_sec % (24 * 60 * 60);
+        tm->tm_mday = tv->tv_sec / (24 * 60 * 60) +
+                (2 * 365 + 1); /* shift base from 1970 to 1968 */
+        tm->tm_min =  tm->tm_sec / 60 % 60;
+        tm->tm_hour = tm->tm_sec / 60 / 60;
+        tm->tm_sec =  tm->tm_sec % 60;
+        tm->tm_year = 68 + 4*(tm->tm_mday / (4*365+1));
+        tm->tm_mday %= (4*365+1);
+        mon_day[1] = 29;
+        while (tm->tm_mday >= mon_day[tm->tm_mon]) {
+                tm->tm_mday -= mon_day[tm->tm_mon];
+                if (++tm->tm_mon == 12) {
+                        tm->tm_mon = 0;
+                        ++tm->tm_year;
+                        mon_day[1] = 28;
+                }
+        }
+        ++tm->tm_mday;
+}
+
+/*
+ * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
+ * I cannot call that code directly from kdb, it has an unconditional
+ * cli()/sti() and calls routines that take locks which can stop the debugger.
+ */
+static void kdb_sysinfo(struct sysinfo *val)
+{
+        struct timespec uptime;
+        do_posix_clock_monotonic_gettime(&uptime);
+        memset(val, 0, sizeof(*val));
+        val->uptime = uptime.tv_sec;
+        val->loads[0] = avenrun[0];
+        val->loads[1] = avenrun[1];
+        val->loads[2] = avenrun[2];
+        val->procs = nr_threads-1;
+        si_meminfo(val);
+
+        return;
+}
+
+/*
+ * kdb_summary - This function implements the 'summary' command.
+ */
+static int kdb_summary(int argc, const char **argv)
+{
+        struct kdb_tm tm;
+        struct sysinfo val;
+
+        if (argc)
+                return KDB_ARGCOUNT;
+
+        kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
+        kdb_printf("release    %s\n", init_uts_ns.name.release);
+        kdb_printf("version    %s\n", init_uts_ns.name.version);
+        kdb_printf("machine    %s\n", init_uts_ns.name.machine);
+        kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
+        kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
+        kdb_printf("ccversion  %s\n", __stringify(CCVERSION));
+
+        kdb_gmtime(&xtime, &tm);
+        kdb_printf("date       %04d-%02d-%02d %02d:%02d:%02d "
+                   "tz_minuteswest %d\n",
+                1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
+                tm.tm_hour, tm.tm_min, tm.tm_sec,
+                sys_tz.tz_minuteswest);
+
+        kdb_sysinfo(&val);
+        kdb_printf("uptime     ");
+        if (val.uptime > (24*60*60)) {
+                int days = val.uptime / (24*60*60);
+                val.uptime %= (24*60*60);
+                kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
+        }
+        kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
+
+        /* lifted from fs/proc/proc_misc.c::loadavg_read_proc() */
+
+#define LOAD_INT(x) ((x) >> FSHIFT)
+#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
+        kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
+                LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
+                LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
+                LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
+#undef LOAD_INT
+#undef LOAD_FRAC
+        /* Display in kilobytes */
+#define K(x) ((x) << (PAGE_SHIFT - 10))
+        kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
+                   "Buffers:        %8lu kB\n",
+                   val.totalram, val.freeram, val.bufferram);
+        return 0;
+}
+
+/*
+ * kdb_per_cpu - This function implements the 'per_cpu' command.
+ */
+static int kdb_per_cpu(int argc, const char **argv)
+{
+        char buf[256], fmtstr[64];
+        kdb_symtab_t symtab;
+        cpumask_t suppress = CPU_MASK_NONE;
+        int cpu, diag;
+        unsigned long addr, val, bytesperword = 0, whichcpu = ~0UL;
+
+        if (argc < 1 || argc > 3)
+                return KDB_ARGCOUNT;
+
+        snprintf(buf, sizeof(buf), "per_cpu__%s", argv[1]);
+        if (!kdbgetsymval(buf, &symtab)) {
+                kdb_printf("%s is not a per_cpu variable\n", argv[1]);
+                return KDB_BADADDR;
+        }
+        if (argc >= 2) {
+                diag = kdbgetularg(argv[2], &bytesperword);
+                if (diag)
+                        return diag;
+        }
+        if (!bytesperword)
+                bytesperword = KDB_WORD_SIZE;
+        else if (bytesperword > KDB_WORD_SIZE)
+                return KDB_BADWIDTH;
+        sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
+        if (argc >= 3) {
+                diag = kdbgetularg(argv[3], &whichcpu);
+                if (diag)
+                        return diag;
+                if (!cpu_online(whichcpu)) {
+                        kdb_printf("cpu %ld is not online\n", whichcpu);
+                        return KDB_BADCPUNUM;
+                }
+        }
+
+        /* Most architectures use __per_cpu_offset[cpu], some use
+         * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
+         */
+#ifdef  __per_cpu_offset
+#define KDB_PCU(cpu) __per_cpu_offset(cpu)
+#else
+#ifdef  CONFIG_SMP
+#define KDB_PCU(cpu) __per_cpu_offset[cpu]
+#else
+#define KDB_PCU(cpu) 0
+#endif
+#endif
+
+        for_each_online_cpu(cpu) {
+                if (whichcpu != ~0UL && whichcpu != cpu)
+                        continue;
+                addr = symtab.sym_start + KDB_PCU(cpu);
+                diag = kdb_getword(&val, addr, bytesperword);
+                if (diag) {
+                        kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
+                                   "read, diag=%d\n", cpu, addr, diag);
+                        continue;
+                }
+#ifdef  CONFIG_SMP
+                if (!val) {
+                        cpu_set(cpu, suppress);
+                        continue;
+                }
+#endif  /* CONFIG_SMP */
+                kdb_printf("%5d ", cpu);
+                kdb_md_line(fmtstr, addr,
+                        bytesperword == KDB_WORD_SIZE,
+                        1, bytesperword, 1, 1, 0);
+        }
+        if (cpus_weight(suppress) == 0)
+                return 0;
+        kdb_printf("Zero suppressed cpu(s):");
+        for (cpu = first_cpu(suppress); cpu < num_possible_cpus();
+             cpu = next_cpu(cpu, suppress)) {
+                kdb_printf(" %d", cpu);
+                if (cpu == num_possible_cpus() - 1 ||
+                    next_cpu(cpu, suppress) != cpu + 1)
+                        continue;
+                while (cpu < num_possible_cpus() &&
+                       next_cpu(cpu, suppress) == cpu + 1)
+                        ++cpu;
+                kdb_printf("-%d", cpu);
+        }
+        kdb_printf("\n");
+
+#undef KDB_PCU
+
+        return 0;
+}
+
+/*
+ * display help for the use of cmd | grep pattern
+ */
+static int kdb_grep_help(int argc, const char **argv)
+{
+        kdb_printf("Usage of  cmd args | grep pattern:\n");
+        kdb_printf("  Any command's output may be filtered through an ");
+        kdb_printf("emulated 'pipe'.\n");
+        kdb_printf("  'grep' is just a key word.\n");
+        kdb_printf("  The pattern may include a very limited set of "
+                   "metacharacters:\n");
+        kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
+        kdb_printf("  And if there are spaces in the pattern, you may "
+                   "quote it:\n");
+        kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
+                   " or \"^pat tern$\"\n");
+        return 0;
+}
+
+/*
+ * kdb_register_repeat - This function is used to register a kernel
+ *      debugger command.
+ * Inputs:
+ *      cmd     Command name
+ *      func    Function to execute the command
+ *      usage   A simple usage string showing arguments
+ *      help    A simple help string describing command
+ *      repeat  Does the command auto repeat on enter?
+ * Returns:
+ *      zero for success, one if a duplicate command.
+ */
+#define kdb_command_extend 50   /* arbitrary */
+int kdb_register_repeat(char *cmd,
+                        kdb_func_t func,
+                        char *usage,
+                        char *help,
+                        short minlen,
+                        kdb_repeat_t repeat)
+{
+        int i;
+        kdbtab_t *kp;
+
+        /*
+         *  Brute force method to determine duplicates
+         */
+        for_each_kdbcmd(kp, i) {
+                if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
+                        kdb_printf("Duplicate kdb command registered: "
+                                "%s, func %p help %s\n", cmd, func, help);
+                        return 1;
+                }
+        }
+
+        /*
+         * Insert command into first available location in table
+         */
+        for_each_kdbcmd(kp, i) {
+                if (kp->cmd_name == NULL)
+                        break;
+        }
+
+        if (i >= kdb_max_commands) {
+                kdbtab_t *new = kmalloc((kdb_max_commands - KDB_BASE_CMD_MAX +
+                         kdb_command_extend) * sizeof(*new), GFP_KDB);
+                if (!new) {
+                        kdb_printf("Could not allocate new kdb_command "
+                                   "table\n");
+                        return 1;
+                }
+                if (kdb_commands) {
+                        memcpy(new, kdb_commands,
+                               kdb_max_commands * sizeof(*new));
+                        kfree(kdb_commands);
+                }
+                memset(new + kdb_max_commands, 0,
+                       kdb_command_extend * sizeof(*new));
+                kdb_commands = new;
+                kp = kdb_commands + kdb_max_commands;
+                kdb_max_commands += kdb_command_extend;
+        }
+
+        kp->cmd_name   = cmd;
+        kp->cmd_func   = func;
+        kp->cmd_usage  = usage;
+        kp->cmd_help   = help;
+        kp->cmd_flags  = 0;
+        kp->cmd_minlen = minlen;
+        kp->cmd_repeat = repeat;
+
+        return 0;
+}
+
+/*
+ * kdb_register - Compatibility register function for commands that do
+ *      not need to specify a repeat state.  Equivalent to
+ *      kdb_register_repeat with KDB_REPEAT_NONE.
+ * Inputs:
+ *      cmd     Command name
+ *      func    Function to execute the command
+ *      usage   A simple usage string showing arguments
+ *      help    A simple help string describing command
+ * Returns:
+ *      zero for success, one if a duplicate command.
+ */
+int kdb_register(char *cmd,
+             kdb_func_t func,
+             char *usage,
+             char *help,
+             short minlen)
+{
+        return kdb_register_repeat(cmd, func, usage, help, minlen,
+                                   KDB_REPEAT_NONE);
+}
+
+/*
+ * kdb_unregister - This function is used to unregister a kernel
+ *      debugger command.  It is generally called when a module which
+ *      implements kdb commands is unloaded.
+ * Inputs:
+ *      cmd     Command name
+ * Returns:
+ *      zero for success, one command not registered.
+ */
+int kdb_unregister(char *cmd)
+{
+        int i;
+        kdbtab_t *kp;
+
+        /*
+         *  find the command.
+         */
+        for (i = 0, kp = kdb_commands; i < kdb_max_commands; i++, kp++) {
+                if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
+                        kp->cmd_name = NULL;
+                        return 0;
+                }
+        }
+
+        /* Couldn't find it.  */
+        return 1;
+}
+
+/* Initialize the kdb command table. */
+static void __init kdb_inittab(void)
+{
+        int i;
+        kdbtab_t *kp;
+
+        for_each_kdbcmd(kp, i)
+                kp->cmd_name = NULL;
+
+        kdb_register_repeat("md", kdb_md, "<vaddr>",
+          "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
+                            KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("mdr", kdb_md, "<vaddr> <bytes>",
+          "Display Raw Memory", 0, KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("mdp", kdb_md, "<paddr> <bytes>",
+          "Display Physical Memory", 0, KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("mds", kdb_md, "<vaddr>",
+          "Display Memory Symbolically", 0, KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("mm", kdb_mm, "<vaddr> <contents>",
+          "Modify Memory Contents", 0, KDB_REPEAT_NO_ARGS);
+        kdb_register_repeat("go", kdb_go, "[<vaddr>]",
+          "Continue Execution", 1, KDB_REPEAT_NONE);
+        kdb_register_repeat("rd", kdb_rd, "",
+          "Display Registers", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("rm", kdb_rm, "<reg> <contents>",
+          "Modify Registers", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("ef", kdb_ef, "<vaddr>",
+          "Display exception frame", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("bt", kdb_bt, "[<vaddr>]",
+          "Stack traceback", 1, KDB_REPEAT_NONE);
+        kdb_register_repeat("btp", kdb_bt, "<pid>",
+          "Display stack for process <pid>", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("bta", kdb_bt, "[DRSTCZEUIMA]",
+          "Display stack all processes", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("btc", kdb_bt, "",
+          "Backtrace current process on each cpu", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("btt", kdb_bt, "<vaddr>",
+          "Backtrace process given its struct task address", 0,
+                            KDB_REPEAT_NONE);
+        kdb_register_repeat("ll", kdb_ll, "<first-element> <linkoffset> <cmd>",
+          "Execute cmd for each element in linked list", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("env", kdb_env, "",
+          "Show environment variables", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("set", kdb_set, "",
+          "Set environment variables", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("help", kdb_help, "",
+          "Display Help Message", 1, KDB_REPEAT_NONE);
+        kdb_register_repeat("?", kdb_help, "",
+          "Display Help Message", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("cpu", kdb_cpu, "<cpunum>",
+          "Switch to new cpu", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("kgdb", kdb_kgdb, "",
+          "Enter kgdb mode", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("ps", kdb_ps, "[<flags>|A]",
+          "Display active task list", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("pid", kdb_pid, "<pidnum>",
+          "Switch to another task", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("reboot", kdb_reboot, "",
+          "Reboot the machine immediately", 0, KDB_REPEAT_NONE);
+#if defined(CONFIG_MODULES)
+        kdb_register_repeat("lsmod", kdb_lsmod, "",
+          "List loaded kernel modules", 0, KDB_REPEAT_NONE);
+#endif
+#if defined(CONFIG_MAGIC_SYSRQ)
+        kdb_register_repeat("sr", kdb_sr, "<key>",
+          "Magic SysRq key", 0, KDB_REPEAT_NONE);
+#endif
+#if defined(CONFIG_PRINTK)
+        kdb_register_repeat("dmesg", kdb_dmesg, "[lines]",
+          "Display syslog buffer", 0, KDB_REPEAT_NONE);
+#endif
+        kdb_register_repeat("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
+          "Define a set of commands, down to endefcmd", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("kill", kdb_kill, "<-signal> <pid>",
+          "Send a signal to a process", 0, KDB_REPEAT_NONE);
+        kdb_register_repeat("summary", kdb_summary, "",
+          "Summarize the system", 4, KDB_REPEAT_NONE);
+        kdb_register_repeat("per_cpu", kdb_per_cpu, "",
+          "Display per_cpu variables", 3, KDB_REPEAT_NONE);
+        kdb_register_repeat("grephelp", kdb_grep_help, "",
+          "Display help on | grep", 0, KDB_REPEAT_NONE);
+}
+
+/* Execute any commands defined in kdb_cmds.  */
+static void __init kdb_cmd_init(void)
+{
+        int i, diag;
+        for (i = 0; kdb_cmds[i]; ++i) {
+                diag = kdb_parse(kdb_cmds[i]);
+                if (diag)
+                        kdb_printf("kdb command %s failed, kdb diag %d\n",
+                                kdb_cmds[i], diag);
+        }
+        if (defcmd_in_progress) {
+                kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
+                kdb_parse("endefcmd");
+        }
+}
+
+/* Intialize kdb_printf, breakpoint tables and kdb state */
+void __init kdb_init(int lvl)
+{
+        static int kdb_init_lvl = KDB_NOT_INITIALIZED;
+        int i;
+
+        if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
+                return;
+        for (i = kdb_init_lvl; i < lvl; i++) {
+                switch (i) {
+                case KDB_NOT_INITIALIZED:
+                        kdb_inittab();          /* Initialize Command Table */
+                        kdb_initbptab();        /* Initialize Breakpoints */
+                        break;
+                case KDB_INIT_EARLY:
+                        kdb_cmd_init();         /* Build kdb_cmds tables */
+                        break;
+                }
+        }
+        kdb_init_lvl = lvl;
+}
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
new file mode 100644
index 000000000000..97d3ba69775d
--- /dev/null
+++ b/kernel/debug/kdb/kdb_private.h
@@ -0,0 +1,300 @@
+#ifndef _KDBPRIVATE_H
+#define _KDBPRIVATE_H
+
+/*
+ * Kernel Debugger Architecture Independent Private Headers
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ */
+
+#include <linux/kgdb.h>
+#include "../debug_core.h"
+
+/* Kernel Debugger Error codes.  Must not overlap with command codes. */
+#define KDB_NOTFOUND    (-1)
+#define KDB_ARGCOUNT    (-2)
+#define KDB_BADWIDTH    (-3)
+#define KDB_BADRADIX    (-4)
+#define KDB_NOTENV      (-5)
+#define KDB_NOENVVALUE  (-6)
+#define KDB_NOTIMP      (-7)
+#define KDB_ENVFULL     (-8)
+#define KDB_ENVBUFFULL  (-9)
+#define KDB_TOOMANYBPT  (-10)
+#define KDB_TOOMANYDBREGS (-11)
+#define KDB_DUPBPT      (-12)
+#define KDB_BPTNOTFOUND (-13)
+#define KDB_BADMODE     (-14)
+#define KDB_BADINT      (-15)
+#define KDB_INVADDRFMT  (-16)
+#define KDB_BADREG      (-17)
+#define KDB_BADCPUNUM   (-18)
+#define KDB_BADLENGTH   (-19)
+#define KDB_NOBP        (-20)
+#define KDB_BADADDR     (-21)
+
+/* Kernel Debugger Command codes.  Must not overlap with error codes. */
+#define KDB_CMD_GO      (-1001)
+#define KDB_CMD_CPU     (-1002)
+#define KDB_CMD_SS      (-1003)
+#define KDB_CMD_SSB     (-1004)
+#define KDB_CMD_KGDB (-1005)
+#define KDB_CMD_KGDB2 (-1006)
+
+/* Internal debug flags */
+#define KDB_DEBUG_FLAG_BP       0x0002  /* Breakpoint subsystem debug */
+#define KDB_DEBUG_FLAG_BB_SUMM  0x0004  /* Basic block analysis, summary only */
+#define KDB_DEBUG_FLAG_AR       0x0008  /* Activation record, generic */
+#define KDB_DEBUG_FLAG_ARA      0x0010  /* Activation record, arch specific */
+#define KDB_DEBUG_FLAG_BB       0x0020  /* All basic block analysis */
+#define KDB_DEBUG_FLAG_STATE    0x0040  /* State flags */
+#define KDB_DEBUG_FLAG_MASK     0xffff  /* All debug flags */
+#define KDB_DEBUG_FLAG_SHIFT    16      /* Shift factor for dbflags */
+
+#define KDB_DEBUG(flag) (kdb_flags & \
+        (KDB_DEBUG_FLAG_##flag << KDB_DEBUG_FLAG_SHIFT))
+#define KDB_DEBUG_STATE(text, value) if (KDB_DEBUG(STATE)) \
+                kdb_print_state(text, value)
+
+#if BITS_PER_LONG == 32
+
+#define KDB_PLATFORM_ENV        "BYTESPERWORD=4"
+
+#define kdb_machreg_fmt         "0x%lx"
+#define kdb_machreg_fmt0        "0x%08lx"
+#define kdb_bfd_vma_fmt         "0x%lx"
+#define kdb_bfd_vma_fmt0        "0x%08lx"
+#define kdb_elfw_addr_fmt       "0x%x"
+#define kdb_elfw_addr_fmt0      "0x%08x"
+#define kdb_f_count_fmt         "%d"
+
+#elif BITS_PER_LONG == 64
+
+#define KDB_PLATFORM_ENV        "BYTESPERWORD=8"
+
+#define kdb_machreg_fmt         "0x%lx"
+#define kdb_machreg_fmt0        "0x%016lx"
+#define kdb_bfd_vma_fmt         "0x%lx"
+#define kdb_bfd_vma_fmt0        "0x%016lx"
+#define kdb_elfw_addr_fmt       "0x%x"
+#define kdb_elfw_addr_fmt0      "0x%016x"
+#define kdb_f_count_fmt         "%ld"
+
+#endif
+
+/*
+ * KDB_MAXBPT describes the total number of breakpoints
+ * supported by this architecure.
+ */
+#define KDB_MAXBPT      16
+
+/* Maximum number of arguments to a function  */
+#define KDB_MAXARGS    16
+
+typedef enum {
+        KDB_REPEAT_NONE = 0,    /* Do not repeat this command */
+        KDB_REPEAT_NO_ARGS,     /* Repeat the command without arguments */
+        KDB_REPEAT_WITH_ARGS,   /* Repeat the command including its arguments */
+} kdb_repeat_t;
+
+typedef int (*kdb_func_t)(int, const char **);
+
+/* Symbol table format returned by kallsyms. */
+typedef struct __ksymtab {
+                unsigned long value;    /* Address of symbol */
+                const char *mod_name;   /* Module containing symbol or
+                                         * "kernel" */
+                unsigned long mod_start;
+                unsigned long mod_end;
+                const char *sec_name;   /* Section containing symbol */
+                unsigned long sec_start;
+                unsigned long sec_end;
+                const char *sym_name;   /* Full symbol name, including
+                                         * any version */
+                unsigned long sym_start;
+                unsigned long sym_end;
+                } kdb_symtab_t;
+extern int kallsyms_symbol_next(char *prefix_name, int flag);
+extern int kallsyms_symbol_complete(char *prefix_name, int max_len);
+
+/* Exported Symbols for kernel loadable modules to use. */
+extern int kdb_register(char *, kdb_func_t, char *, char *, short);
+extern int kdb_register_repeat(char *, kdb_func_t, char *, char *,
+                               short, kdb_repeat_t);
+extern int kdb_unregister(char *);
+
+extern int kdb_getarea_size(void *, unsigned long, size_t);
+extern int kdb_putarea_size(unsigned long, void *, size_t);
+
+/*
+ * Like get_user and put_user, kdb_getarea and kdb_putarea take variable
+ * names, not pointers.  The underlying *_size functions take pointers.
+ */
+#define kdb_getarea(x, addr) kdb_getarea_size(&(x), addr, sizeof((x)))
+#define kdb_putarea(addr, x) kdb_putarea_size(addr, &(x), sizeof((x)))
+
+extern int kdb_getphysword(unsigned long *word,
+                        unsigned long addr, size_t size);
+extern int kdb_getword(unsigned long *, unsigned long, size_t);
+extern int kdb_putword(unsigned long, unsigned long, size_t);
+
+extern int kdbgetularg(const char *, unsigned long *);
+extern int kdb_set(int, const char **);
+extern char *kdbgetenv(const char *);
+extern int kdbgetintenv(const char *, int *);
+extern int kdbgetaddrarg(int, const char **, int*, unsigned long *,
+                         long *, char **);
+extern int kdbgetsymval(const char *, kdb_symtab_t *);
+extern int kdbnearsym(unsigned long, kdb_symtab_t *);
+extern void kdbnearsym_cleanup(void);
+extern char *kdb_strdup(const char *str, gfp_t type);
+extern void kdb_symbol_print(unsigned long, const kdb_symtab_t *, unsigned int);
+
+/* Routine for debugging the debugger state. */
+extern void kdb_print_state(const char *, int);
+
+extern int kdb_state;
+#define KDB_STATE_KDB           0x00000001      /* Cpu is inside kdb */
+#define KDB_STATE_LEAVING       0x00000002      /* Cpu is leaving kdb */
+#define KDB_STATE_CMD           0x00000004      /* Running a kdb command */
+#define KDB_STATE_KDB_CONTROL   0x00000008      /* This cpu is under
+                                                 * kdb control */
+#define KDB_STATE_HOLD_CPU      0x00000010      /* Hold this cpu inside kdb */
+#define KDB_STATE_DOING_SS      0x00000020      /* Doing ss command */
+#define KDB_STATE_DOING_SSB     0x00000040      /* Doing ssb command,
+                                                 * DOING_SS is also set */
+#define KDB_STATE_SSBPT         0x00000080      /* Install breakpoint
+                                                 * after one ss, independent of
+                                                 * DOING_SS */
+#define KDB_STATE_REENTRY       0x00000100      /* Valid re-entry into kdb */
+#define KDB_STATE_SUPPRESS      0x00000200      /* Suppress error messages */
+#define KDB_STATE_PAGER         0x00000400      /* pager is available */
+#define KDB_STATE_GO_SWITCH     0x00000800      /* go is switching
+                                                 * back to initial cpu */
+#define KDB_STATE_PRINTF_LOCK   0x00001000      /* Holds kdb_printf lock */
+#define KDB_STATE_WAIT_IPI      0x00002000      /* Waiting for kdb_ipi() NMI */
+#define KDB_STATE_RECURSE       0x00004000      /* Recursive entry to kdb */
+#define KDB_STATE_IP_ADJUSTED   0x00008000      /* Restart IP has been
+                                                 * adjusted */
+#define KDB_STATE_GO1           0x00010000      /* go only releases one cpu */
+#define KDB_STATE_KEYBOARD      0x00020000      /* kdb entered via
+                                                 * keyboard on this cpu */
+#define KDB_STATE_KEXEC         0x00040000      /* kexec issued */
+#define KDB_STATE_DOING_KGDB    0x00080000      /* kgdb enter now issued */
+#define KDB_STATE_DOING_KGDB2   0x00100000      /* kgdb enter now issued */
+#define KDB_STATE_KGDB_TRANS    0x00200000      /* Transition to kgdb */
+#define KDB_STATE_ARCH          0xff000000      /* Reserved for arch
+                                                 * specific use */
+
+#define KDB_STATE(flag) (kdb_state & KDB_STATE_##flag)
+#define KDB_STATE_SET(flag) ((void)(kdb_state |= KDB_STATE_##flag))
+#define KDB_STATE_CLEAR(flag) ((void)(kdb_state &= ~KDB_STATE_##flag))
+
+extern int kdb_nextline; /* Current number of lines displayed */
+
+typedef struct _kdb_bp {
+        unsigned long   bp_addr;        /* Address breakpoint is present at */
+        unsigned int    bp_free:1;      /* This entry is available */
+        unsigned int    bp_enabled:1;   /* Breakpoint is active in register */
+        unsigned int    bp_type:4;      /* Uses hardware register */
+        unsigned int    bp_installed:1; /* Breakpoint is installed */
+        unsigned int    bp_delay:1;     /* Do delayed bp handling */
+        unsigned int    bp_delayed:1;   /* Delayed breakpoint */
+        unsigned int    bph_length;     /* HW break length */
+} kdb_bp_t;
+
+#ifdef CONFIG_KGDB_KDB
+extern kdb_bp_t kdb_breakpoints[/* KDB_MAXBPT */];
+
+/* The KDB shell command table */
+typedef struct _kdbtab {
+        char    *cmd_name;              /* Command name */
+        kdb_func_t cmd_func;            /* Function to execute command */
+        char    *cmd_usage;             /* Usage String for this command */
+        char    *cmd_help;              /* Help message for this command */
+        short    cmd_flags;             /* Parsing flags */
+        short    cmd_minlen;            /* Minimum legal # command
+                                         * chars required */
+        kdb_repeat_t cmd_repeat;        /* Does command auto repeat on enter? */
+} kdbtab_t;
+
+extern int kdb_bt(int, const char **);  /* KDB display back trace */
+
+/* KDB breakpoint management functions */
+extern void kdb_initbptab(void);
+extern void kdb_bp_install(struct pt_regs *);
+extern void kdb_bp_remove(void);
+
+typedef enum {
+        KDB_DB_BPT,     /* Breakpoint */
+        KDB_DB_SS,      /* Single-step trap */
+        KDB_DB_SSB,     /* Single step to branch */
+        KDB_DB_SSBPT,   /* Single step over breakpoint */
+        KDB_DB_NOBPT    /* Spurious breakpoint */
+} kdb_dbtrap_t;
+
+extern int kdb_main_loop(kdb_reason_t, kdb_reason_t,
+                         int, kdb_dbtrap_t, struct pt_regs *);
+
+/* Miscellaneous functions and data areas */
+extern int kdb_grepping_flag;
+extern char kdb_grep_string[];
+extern int kdb_grep_leading;
+extern int kdb_grep_trailing;
+extern char *kdb_cmds[];
+extern void kdb_syslog_data(char *syslog_data[]);
+extern unsigned long kdb_task_state_string(const char *);
+extern char kdb_task_state_char (const struct task_struct *);
+extern unsigned long kdb_task_state(const struct task_struct *p,
+                                    unsigned long mask);
+extern void kdb_ps_suppressed(void);
+extern void kdb_ps1(const struct task_struct *p);
+extern void kdb_print_nameval(const char *name, unsigned long val);
+extern void kdb_send_sig_info(struct task_struct *p, struct siginfo *info);
+extern void kdb_meminfo_proc_show(void);
+extern const char *kdb_walk_kallsyms(loff_t *pos);
+extern char *kdb_getstr(char *, size_t, char *);
+
+/* Defines for kdb_symbol_print */
+#define KDB_SP_SPACEB   0x0001          /* Space before string */
+#define KDB_SP_SPACEA   0x0002          /* Space after string */
+#define KDB_SP_PAREN    0x0004          /* Parenthesis around string */
+#define KDB_SP_VALUE    0x0008          /* Print the value of the address */
+#define KDB_SP_SYMSIZE  0x0010          /* Print the size of the symbol */
+#define KDB_SP_NEWLINE  0x0020          /* Newline after string */
+#define KDB_SP_DEFAULT (KDB_SP_VALUE|KDB_SP_PAREN)
+
+#define KDB_TSK(cpu) kgdb_info[cpu].task
+#define KDB_TSKREGS(cpu) kgdb_info[cpu].debuggerinfo
+
+extern struct task_struct *kdb_curr_task(int);
+
+#define kdb_task_has_cpu(p) (task_curr(p))
+
+/* Simplify coexistence with NPTL */
+#define kdb_do_each_thread(g, p) do_each_thread(g, p)
+#define kdb_while_each_thread(g, p) while_each_thread(g, p)
+
+#define GFP_KDB (in_interrupt() ? GFP_ATOMIC : GFP_KERNEL)
+
+extern void *debug_kmalloc(size_t size, gfp_t flags);
+extern void debug_kfree(void *);
+extern void debug_kusage(void);
+
+extern void kdb_set_current_task(struct task_struct *);
+extern struct task_struct *kdb_current_task;
+#ifdef CONFIG_MODULES
+extern struct list_head *kdb_modules;
+#endif /* CONFIG_MODULES */
+
+extern char kdb_prompt_str[];
+
+#define KDB_WORD_SIZE   ((int)sizeof(unsigned long))
+
+#endif /* CONFIG_KGDB_KDB */
+#endif  /* !_KDBPRIVATE_H */
diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c
new file mode 100644
index 000000000000..45344d5c53dd
--- /dev/null
+++ b/kernel/debug/kdb/kdb_support.c
@@ -0,0 +1,927 @@
+/*
+ * Kernel Debugger Architecture Independent Support Functions
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
+ * 03/02/13    added new 2.5 kallsyms <xavier.bru@bull.net>
+ */
+
+#include <stdarg.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/kallsyms.h>
+#include <linux/stddef.h>
+#include <linux/vmalloc.h>
+#include <linux/ptrace.h>
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/hardirq.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <linux/kdb.h>
+#include <linux/slab.h>
+#include "kdb_private.h"
+
+/*
+ * kdbgetsymval - Return the address of the given symbol.
+ *
+ * Parameters:
+ *      symname Character string containing symbol name
+ *      symtab  Structure to receive results
+ * Returns:
+ *      0       Symbol not found, symtab zero filled
+ *      1       Symbol mapped to module/symbol/section, data in symtab
+ */
+int kdbgetsymval(const char *symname, kdb_symtab_t *symtab)
+{
+        if (KDB_DEBUG(AR))
+                kdb_printf("kdbgetsymval: symname=%s, symtab=%p\n", symname,
+                           symtab);
+        memset(symtab, 0, sizeof(*symtab));
+        symtab->sym_start = kallsyms_lookup_name(symname);
+        if (symtab->sym_start) {
+                if (KDB_DEBUG(AR))
+                        kdb_printf("kdbgetsymval: returns 1, "
+                                   "symtab->sym_start=0x%lx\n",
+                                   symtab->sym_start);
+                return 1;
+        }
+        if (KDB_DEBUG(AR))
+                kdb_printf("kdbgetsymval: returns 0\n");
+        return 0;
+}
+EXPORT_SYMBOL(kdbgetsymval);
+
+static char *kdb_name_table[100];       /* arbitrary size */
+
+/*
+ * kdbnearsym - Return the name of the symbol with the nearest address
+ *      less than 'addr'.
+ *
+ * Parameters:
+ *      addr    Address to check for symbol near
+ *      symtab  Structure to receive results
+ * Returns:
+ *      0       No sections contain this address, symtab zero filled
+ *      1       Address mapped to module/symbol/section, data in symtab
+ * Remarks:
+ *      2.6 kallsyms has a "feature" where it unpacks the name into a
+ *      string.  If that string is reused before the caller expects it
+ *      then the caller sees its string change without warning.  To
+ *      avoid cluttering up the main kdb code with lots of kdb_strdup,
+ *      tests and kfree calls, kdbnearsym maintains an LRU list of the
+ *      last few unique strings.  The list is sized large enough to
+ *      hold active strings, no kdb caller of kdbnearsym makes more
+ *      than ~20 later calls before using a saved value.
+ */
+int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab)
+{
+        int ret = 0;
+        unsigned long symbolsize;
+        unsigned long offset;
+#define knt1_size 128           /* must be >= kallsyms table size */
+        char *knt1 = NULL;
+
+        if (KDB_DEBUG(AR))
+                kdb_printf("kdbnearsym: addr=0x%lx, symtab=%p\n", addr, symtab);
+        memset(symtab, 0, sizeof(*symtab));
+
+        if (addr < 4096)
+                goto out;
+        knt1 = debug_kmalloc(knt1_size, GFP_ATOMIC);
+        if (!knt1) {
+                kdb_printf("kdbnearsym: addr=0x%lx cannot kmalloc knt1\n",
+                           addr);
+                goto out;
+        }
+        symtab->sym_name = kallsyms_lookup(addr, &symbolsize , &offset,
+                                (char **)(&symtab->mod_name), knt1);
+        if (offset > 8*1024*1024) {
+                symtab->sym_name = NULL;
+                addr = offset = symbolsize = 0;
+        }
+        symtab->sym_start = addr - offset;
+        symtab->sym_end = symtab->sym_start + symbolsize;
+        ret = symtab->sym_name != NULL && *(symtab->sym_name) != '\0';
+
+        if (ret) {
+                int i;
+                /* Another 2.6 kallsyms "feature".  Sometimes the sym_name is
+                 * set but the buffer passed into kallsyms_lookup is not used,
+                 * so it contains garbage.  The caller has to work out which
+                 * buffer needs to be saved.
+                 *
+                 * What was Rusty smoking when he wrote that code?
+                 */
+                if (symtab->sym_name != knt1) {
+                        strncpy(knt1, symtab->sym_name, knt1_size);
+                        knt1[knt1_size-1] = '\0';
+                }
+                for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) {
+                        if (kdb_name_table[i] &&
+                            strcmp(kdb_name_table[i], knt1) == 0)
+                                break;
+                }
+                if (i >= ARRAY_SIZE(kdb_name_table)) {
+                        debug_kfree(kdb_name_table[0]);
+                        memcpy(kdb_name_table, kdb_name_table+1,
+                               sizeof(kdb_name_table[0]) *
+                               (ARRAY_SIZE(kdb_name_table)-1));
+                } else {
+                        debug_kfree(knt1);
+                        knt1 = kdb_name_table[i];
+                        memcpy(kdb_name_table+i, kdb_name_table+i+1,
+                               sizeof(kdb_name_table[0]) *
+                               (ARRAY_SIZE(kdb_name_table)-i-1));
+                }
+                i = ARRAY_SIZE(kdb_name_table) - 1;
+                kdb_name_table[i] = knt1;
+                symtab->sym_name = kdb_name_table[i];
+                knt1 = NULL;
+        }
+
+        if (symtab->mod_name == NULL)
+                symtab->mod_name = "kernel";
+        if (KDB_DEBUG(AR))
+                kdb_printf("kdbnearsym: returns %d symtab->sym_start=0x%lx, "
+                   "symtab->mod_name=%p, symtab->sym_name=%p (%s)\n", ret,
+                   symtab->sym_start, symtab->mod_name, symtab->sym_name,
+                   symtab->sym_name);
+
+out:
+        debug_kfree(knt1);
+        return ret;
+}
+
+void kdbnearsym_cleanup(void)
+{
+        int i;
+        for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) {
+                if (kdb_name_table[i]) {
+                        debug_kfree(kdb_name_table[i]);
+                        kdb_name_table[i] = NULL;
+                }
+        }
+}
+
+static char ks_namebuf[KSYM_NAME_LEN+1], ks_namebuf_prev[KSYM_NAME_LEN+1];
+
+/*
+ * kallsyms_symbol_complete
+ *
+ * Parameters:
+ *      prefix_name     prefix of a symbol name to lookup
+ *      max_len         maximum length that can be returned
+ * Returns:
+ *      Number of symbols which match the given prefix.
+ * Notes:
+ *      prefix_name is changed to contain the longest unique prefix that
+ *      starts with this prefix (tab completion).
+ */
+int kallsyms_symbol_complete(char *prefix_name, int max_len)
+{
+        loff_t pos = 0;
+        int prefix_len = strlen(prefix_name), prev_len = 0;
+        int i, number = 0;
+        const char *name;
+
+        while ((name = kdb_walk_kallsyms(&pos))) {
+                if (strncmp(name, prefix_name, prefix_len) == 0) {
+                        strcpy(ks_namebuf, name);
+                        /* Work out the longest name that matches the prefix */
+                        if (++number == 1) {
+                                prev_len = min_t(int, max_len-1,
+                                                 strlen(ks_namebuf));
+                                memcpy(ks_namebuf_prev, ks_namebuf, prev_len);
+                                ks_namebuf_prev[prev_len] = '\0';
+                                continue;
+                        }
+                        for (i = 0; i < prev_len; i++) {
+                                if (ks_namebuf[i] != ks_namebuf_prev[i]) {
+                                        prev_len = i;
+                                        ks_namebuf_prev[i] = '\0';
+                                        break;
+                                }
+                        }
+                }
+        }
+        if (prev_len > prefix_len)
+                memcpy(prefix_name, ks_namebuf_prev, prev_len+1);
+        return number;
+}
+
+/*
+ * kallsyms_symbol_next
+ *
+ * Parameters:
+ *      prefix_name     prefix of a symbol name to lookup
+ *      flag    0 means search from the head, 1 means continue search.
+ * Returns:
+ *      1 if a symbol matches the given prefix.
+ *      0 if no string found
+ */
+int kallsyms_symbol_next(char *prefix_name, int flag)
+{
+        int prefix_len = strlen(prefix_name);
+        static loff_t pos;
+        const char *name;
+
+        if (!flag)
+                pos = 0;
+
+        while ((name = kdb_walk_kallsyms(&pos))) {
+                if (strncmp(name, prefix_name, prefix_len) == 0) {
+                        strncpy(prefix_name, name, strlen(name)+1);
+                        return 1;
+                }
+        }
+        return 0;
+}
+
+/*
+ * kdb_symbol_print - Standard method for printing a symbol name and offset.
+ * Inputs:
+ *      addr    Address to be printed.
+ *      symtab  Address of symbol data, if NULL this routine does its
+ *              own lookup.
+ *      punc    Punctuation for string, bit field.
+ * Remarks:
+ *      The string and its punctuation is only printed if the address
+ *      is inside the kernel, except that the value is always printed
+ *      when requested.
+ */
+void kdb_symbol_print(unsigned long addr, const kdb_symtab_t *symtab_p,
+                      unsigned int punc)
+{
+        kdb_symtab_t symtab, *symtab_p2;
+        if (symtab_p) {
+                symtab_p2 = (kdb_symtab_t *)symtab_p;
+        } else {
+                symtab_p2 = &symtab;
+                kdbnearsym(addr, symtab_p2);
+        }
+        if (!(symtab_p2->sym_name || (punc & KDB_SP_VALUE)))
+                return;
+        if (punc & KDB_SP_SPACEB)
+                kdb_printf(" ");
+        if (punc & KDB_SP_VALUE)
+                kdb_printf(kdb_machreg_fmt0, addr);
+        if (symtab_p2->sym_name) {
+                if (punc & KDB_SP_VALUE)
+                        kdb_printf(" ");
+                if (punc & KDB_SP_PAREN)
+                        kdb_printf("(");
+                if (strcmp(symtab_p2->mod_name, "kernel"))
+                        kdb_printf("[%s]", symtab_p2->mod_name);
+                kdb_printf("%s", symtab_p2->sym_name);
+                if (addr != symtab_p2->sym_start)
+                        kdb_printf("+0x%lx", addr - symtab_p2->sym_start);
+                if (punc & KDB_SP_SYMSIZE)
+                        kdb_printf("/0x%lx",
+                                   symtab_p2->sym_end - symtab_p2->sym_start);
+                if (punc & KDB_SP_PAREN)
+                        kdb_printf(")");
+        }
+        if (punc & KDB_SP_SPACEA)
+                kdb_printf(" ");
+        if (punc & KDB_SP_NEWLINE)
+                kdb_printf("\n");
+}
+
+/*
+ * kdb_strdup - kdb equivalent of strdup, for disasm code.
+ * Inputs:
+ *      str     The string to duplicate.
+ *      type    Flags to kmalloc for the new string.
+ * Returns:
+ *      Address of the new string, NULL if storage could not be allocated.
+ * Remarks:
+ *      This is not in lib/string.c because it uses kmalloc which is not
+ *      available when string.o is used in boot loaders.
+ */
+char *kdb_strdup(const char *str, gfp_t type)
+{
+        int n = strlen(str)+1;
+        char *s = kmalloc(n, type);
+        if (!s)
+                return NULL;
+        return strcpy(s, str);
+}
+
+/*
+ * kdb_getarea_size - Read an area of data.  The kdb equivalent of
+ *      copy_from_user, with kdb messages for invalid addresses.
+ * Inputs:
+ *      res     Pointer to the area to receive the result.
+ *      addr    Address of the area to copy.
+ *      size    Size of the area.
+ * Returns:
+ *      0 for success, < 0 for error.
+ */
+int kdb_getarea_size(void *res, unsigned long addr, size_t size)
+{
+        int ret = probe_kernel_read((char *)res, (char *)addr, size);
+        if (ret) {
+                if (!KDB_STATE(SUPPRESS)) {
+                        kdb_printf("kdb_getarea: Bad address 0x%lx\n", addr);
+                        KDB_STATE_SET(SUPPRESS);
+                }
+                ret = KDB_BADADDR;
+        } else {
+                KDB_STATE_CLEAR(SUPPRESS);
+        }
+        return ret;
+}
+
+/*
+ * kdb_putarea_size - Write an area of data.  The kdb equivalent of
+ *      copy_to_user, with kdb messages for invalid addresses.
+ * Inputs:
+ *      addr    Address of the area to write to.
+ *      res     Pointer to the area holding the data.
+ *      size    Size of the area.
+ * Returns:
+ *      0 for success, < 0 for error.
+ */
+int kdb_putarea_size(unsigned long addr, void *res, size_t size)
+{
+        int ret = probe_kernel_read((char *)addr, (char *)res, size);
+        if (ret) {
+                if (!KDB_STATE(SUPPRESS)) {
+                        kdb_printf("kdb_putarea: Bad address 0x%lx\n", addr);
+                        KDB_STATE_SET(SUPPRESS);
+                }
+                ret = KDB_BADADDR;
+        } else {
+                KDB_STATE_CLEAR(SUPPRESS);
+        }
+        return ret;
+}
+
+/*
+ * kdb_getphys - Read data from a physical address. Validate the
+ *      address is in range, use kmap_atomic() to get data
+ *      similar to kdb_getarea() - but for phys addresses
+ * Inputs:
+ *      res     Pointer to the word to receive the result
+ *      addr    Physical address of the area to copy
+ *      size    Size of the area
+ * Returns:
+ *      0 for success, < 0 for error.
+ */
+static int kdb_getphys(void *res, unsigned long addr, size_t size)
+{
+        unsigned long pfn;
+        void *vaddr;
+        struct page *page;
+
+        pfn = (addr >> PAGE_SHIFT);
+        if (!pfn_valid(pfn))
+                return 1;
+        page = pfn_to_page(pfn);
+        vaddr = kmap_atomic(page, KM_KDB);
+        memcpy(res, vaddr + (addr & (PAGE_SIZE - 1)), size);
+        kunmap_atomic(vaddr, KM_KDB);
+
+        return 0;
+}
+
+/*
+ * kdb_getphysword
+ * Inputs:
+ *      word    Pointer to the word to receive the result.
+ *      addr    Address of the area to copy.
+ *      size    Size of the area.
+ * Returns:
+ *      0 for success, < 0 for error.
+ */
+int kdb_getphysword(unsigned long *word, unsigned long addr, size_t size)
+{
+        int diag;
+        __u8  w1;
+        __u16 w2;
+        __u32 w4;
+        __u64 w8;
+        *word = 0;      /* Default value if addr or size is invalid */
+
+        switch (size) {
+        case 1:
+                diag = kdb_getphys(&w1, addr, sizeof(w1));
+                if (!diag)
+                        *word = w1;
+                break;
+        case 2:
+                diag = kdb_getphys(&w2, addr, sizeof(w2));
+                if (!diag)
+                        *word = w2;
+                break;
+        case 4:
+                diag = kdb_getphys(&w4, addr, sizeof(w4));
+                if (!diag)
+                        *word = w4;
+                break;
+        case 8:
+                if (size <= sizeof(*word)) {
+                        diag = kdb_getphys(&w8, addr, sizeof(w8));
+                        if (!diag)
+                                *word = w8;
+                        break;
+                }
+                /* drop through */
+        default:
+                diag = KDB_BADWIDTH;
+                kdb_printf("kdb_getphysword: bad width %ld\n", (long) size);
+        }
+        return diag;
+}
+
+/*
+ * kdb_getword - Read a binary value.  Unlike kdb_getarea, this treats
+ *      data as numbers.
+ * Inputs:
+ *      word    Pointer to the word to receive the result.
+ *      addr    Address of the area to copy.
+ *      size    Size of the area.
+ * Returns:
+ *      0 for success, < 0 for error.
+ */
+int kdb_getword(unsigned long *word, unsigned long addr, size_t size)
+{
+        int diag;
+        __u8  w1;
+        __u16 w2;
+        __u32 w4;
+        __u64 w8;
+        *word = 0;      /* Default value if addr or size is invalid */
+        switch (size) {
+        case 1:
+                diag = kdb_getarea(w1, addr);
+                if (!diag)
+                        *word = w1;
+                break;
+        case 2:
+                diag = kdb_getarea(w2, addr);
+                if (!diag)
+                        *word = w2;
+                break;
+        case 4:
+                diag = kdb_getarea(w4, addr);
+                if (!diag)
+                        *word = w4;
+                break;
+        case 8:
+                if (size <= sizeof(*word)) {
+                        diag = kdb_getarea(w8, addr);
+                        if (!diag)
+                                *word = w8;
+                        break;
+                }
+                /* drop through */
+        default:
+                diag = KDB_BADWIDTH;
+                kdb_printf("kdb_getword: bad width %ld\n", (long) size);
+        }
+        return diag;
+}
+
+/*
+ * kdb_putword - Write a binary value.  Unlike kdb_putarea, this
+ *      treats data as numbers.
+ * Inputs:
+ *      addr    Address of the area to write to..
+ *      word    The value to set.
+ *      size    Size of the area.
+ * Returns:
+ *      0 for success, < 0 for error.
+ */
+int kdb_putword(unsigned long addr, unsigned long word, size_t size)
+{
+        int diag;
+        __u8  w1;
+        __u16 w2;
+        __u32 w4;
+        __u64 w8;
+        switch (size) {
+        case 1:
+                w1 = word;
+                diag = kdb_putarea(addr, w1);
+                break;
+        case 2:
+                w2 = word;
+                diag = kdb_putarea(addr, w2);
+                break;
+        case 4:
+                w4 = word;
+                diag = kdb_putarea(addr, w4);
+                break;
+        case 8:
+                if (size <= sizeof(word)) {
+                        w8 = word;
+                        diag = kdb_putarea(addr, w8);
+                        break;
+                }
+                /* drop through */
+        default:
+                diag = KDB_BADWIDTH;
+                kdb_printf("kdb_putword: bad width %ld\n", (long) size);
+        }
+        return diag;
+}
+
+/*
+ * kdb_task_state_string - Convert a string containing any of the
+ *      letters DRSTCZEUIMA to a mask for the process state field and
+ *      return the value.  If no argument is supplied, return the mask
+ *      that corresponds to environment variable PS, DRSTCZEU by
+ *      default.
+ * Inputs:
+ *      s       String to convert
+ * Returns:
+ *      Mask for process state.
+ * Notes:
+ *      The mask folds data from several sources into a single long value, so
+ *      be carefull not to overlap the bits.  TASK_* bits are in the LSB,
+ *      special cases like UNRUNNABLE are in the MSB.  As of 2.6.10-rc1 there
+ *      is no overlap between TASK_* and EXIT_* but that may not always be
+ *      true, so EXIT_* bits are shifted left 16 bits before being stored in
+ *      the mask.
+ */
+
+/* unrunnable is < 0 */
+#define UNRUNNABLE      (1UL << (8*sizeof(unsigned long) - 1))
+#define RUNNING         (1UL << (8*sizeof(unsigned long) - 2))
+#define IDLE            (1UL << (8*sizeof(unsigned long) - 3))
+#define DAEMON          (1UL << (8*sizeof(unsigned long) - 4))
+
+unsigned long kdb_task_state_string(const char *s)
+{
+        long res = 0;
+        if (!s) {
+                s = kdbgetenv("PS");
+                if (!s)
+                        s = "DRSTCZEU"; /* default value for ps */
+        }
+        while (*s) {
+                switch (*s) {
+                case 'D':
+                        res |= TASK_UNINTERRUPTIBLE;
+                        break;
+                case 'R':
+                        res |= RUNNING;
+                        break;
+                case 'S':
+                        res |= TASK_INTERRUPTIBLE;
+                        break;
+                case 'T':
+                        res |= TASK_STOPPED;
+                        break;
+                case 'C':
+                        res |= TASK_TRACED;
+                        break;
+                case 'Z':
+                        res |= EXIT_ZOMBIE << 16;
+                        break;
+                case 'E':
+                        res |= EXIT_DEAD << 16;
+                        break;
+                case 'U':
+                        res |= UNRUNNABLE;
+                        break;
+                case 'I':
+                        res |= IDLE;
+                        break;
+                case 'M':
+                        res |= DAEMON;
+                        break;
+                case 'A':
+                        res = ~0UL;
+                        break;
+                default:
+                          kdb_printf("%s: unknown flag '%c' ignored\n",
+                                     __func__, *s);
+                          break;
+                }
+                ++s;
+        }
+        return res;
+}
+
+/*
+ * kdb_task_state_char - Return the character that represents the task state.
+ * Inputs:
+ *      p       struct task for the process
+ * Returns:
+ *      One character to represent the task state.
+ */
+char kdb_task_state_char (const struct task_struct *p)
+{
+        int cpu;
+        char state;
+        unsigned long tmp;
+
+        if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
+                return 'E';
+
+        cpu = kdb_process_cpu(p);
+        state = (p->state == 0) ? 'R' :
+                (p->state < 0) ? 'U' :
+                (p->state & TASK_UNINTERRUPTIBLE) ? 'D' :
+                (p->state & TASK_STOPPED) ? 'T' :
+                (p->state & TASK_TRACED) ? 'C' :
+                (p->exit_state & EXIT_ZOMBIE) ? 'Z' :
+                (p->exit_state & EXIT_DEAD) ? 'E' :
+                (p->state & TASK_INTERRUPTIBLE) ? 'S' : '?';
+        if (p->pid == 0) {
+                /* Idle task.  Is it really idle, apart from the kdb
+                 * interrupt? */
+                if (!kdb_task_has_cpu(p) || kgdb_info[cpu].irq_depth == 1) {
+                        if (cpu != kdb_initial_cpu)
+                                state = 'I';    /* idle task */
+                }
+        } else if (!p->mm && state == 'S') {
+                state = 'M';    /* sleeping system daemon */
+        }
+        return state;
+}
+
+/*
+ * kdb_task_state - Return true if a process has the desired state
+ *      given by the mask.
+ * Inputs:
+ *      p       struct task for the process
+ *      mask    mask from kdb_task_state_string to select processes
+ * Returns:
+ *      True if the process matches at least one criteria defined by the mask.
+ */
+unsigned long kdb_task_state(const struct task_struct *p, unsigned long mask)
+{
+        char state[] = { kdb_task_state_char(p), '\0' };
+        return (mask & kdb_task_state_string(state)) != 0;
+}
+
+/*
+ * kdb_print_nameval - Print a name and its value, converting the
+ *      value to a symbol lookup if possible.
+ * Inputs:
+ *      name    field name to print
+ *      val     value of field
+ */
+void kdb_print_nameval(const char *name, unsigned long val)
+{
+        kdb_symtab_t symtab;
+        kdb_printf("  %-11.11s ", name);
+        if (kdbnearsym(val, &symtab))
+                kdb_symbol_print(val, &symtab,
+                                 KDB_SP_VALUE|KDB_SP_SYMSIZE|KDB_SP_NEWLINE);
+        else
+                kdb_printf("0x%lx\n", val);
+}
+
+/* Last ditch allocator for debugging, so we can still debug even when
+ * the GFP_ATOMIC pool has been exhausted.  The algorithms are tuned
+ * for space usage, not for speed.  One smallish memory pool, the free
+ * chain is always in ascending address order to allow coalescing,
+ * allocations are done in brute force best fit.
+ */
+
+struct debug_alloc_header {
+        u32 next;       /* offset of next header from start of pool */
+        u32 size;
+        void *caller;
+};
+
+/* The memory returned by this allocator must be aligned, which means
+ * so must the header size.  Do not assume that sizeof(struct
+ * debug_alloc_header) is a multiple of the alignment, explicitly
+ * calculate the overhead of this header, including the alignment.
+ * The rest of this code must not use sizeof() on any header or
+ * pointer to a header.
+ */
+#define dah_align 8
+#define dah_overhead ALIGN(sizeof(struct debug_alloc_header), dah_align)
+
+static u64 debug_alloc_pool_aligned[256*1024/dah_align];        /* 256K pool */
+static char *debug_alloc_pool = (char *)debug_alloc_pool_aligned;
+static u32 dah_first, dah_first_call = 1, dah_used, dah_used_max;
+
+/* Locking is awkward.  The debug code is called from all contexts,
+ * including non maskable interrupts.  A normal spinlock is not safe
+ * in NMI context.  Try to get the debug allocator lock, if it cannot
+ * be obtained after a second then give up.  If the lock could not be
+ * previously obtained on this cpu then only try once.
+ *
+ * sparse has no annotation for "this function _sometimes_ acquires a
+ * lock", so fudge the acquire/release notation.
+ */
+static DEFINE_SPINLOCK(dap_lock);
+static int get_dap_lock(void)
+        __acquires(dap_lock)
+{
+        static int dap_locked = -1;
+        int count;
+        if (dap_locked == smp_processor_id())
+                count = 1;
+        else
+                count = 1000;
+        while (1) {
+                if (spin_trylock(&dap_lock)) {
+                        dap_locked = -1;
+                        return 1;
+                }
+                if (!count--)
+                        break;
+                udelay(1000);
+        }
+        dap_locked = smp_processor_id();
+        __acquire(dap_lock);
+        return 0;
+}
+
+void *debug_kmalloc(size_t size, gfp_t flags)
+{
+        unsigned int rem, h_offset;
+        struct debug_alloc_header *best, *bestprev, *prev, *h;
+        void *p = NULL;
+        if (!get_dap_lock()) {
+                __release(dap_lock);    /* we never actually got it */
+                return NULL;
+        }
+        h = (struct debug_alloc_header *)(debug_alloc_pool + dah_first);
+        if (dah_first_call) {
+                h->size = sizeof(debug_alloc_pool_aligned) - dah_overhead;
+                dah_first_call = 0;
+        }
+        size = ALIGN(size, dah_align);
+        prev = best = bestprev = NULL;
+        while (1) {
+                if (h->size >= size && (!best || h->size < best->size)) {
+                        best = h;
+                        bestprev = prev;
+                        if (h->size == size)
+                                break;
+                }
+                if (!h->next)
+                        break;
+                prev = h;
+                h = (struct debug_alloc_header *)(debug_alloc_pool + h->next);
+        }
+        if (!best)
+                goto out;
+        rem = best->size - size;
+        /* The pool must always contain at least one header */
+        if (best->next == 0 && bestprev == NULL && rem < dah_overhead)
+                goto out;
+        if (rem >= dah_overhead) {
+                best->size = size;
+                h_offset = ((char *)best - debug_alloc_pool) +
+                           dah_overhead + best->size;
+                h = (struct debug_alloc_header *)(debug_alloc_pool + h_offset);
+                h->size = rem - dah_overhead;
+                h->next = best->next;
+        } else
+                h_offset = best->next;
+        best->caller = __builtin_return_address(0);
+        dah_used += best->size;
+        dah_used_max = max(dah_used, dah_used_max);
+        if (bestprev)
+                bestprev->next = h_offset;
+        else
+                dah_first = h_offset;
+        p = (char *)best + dah_overhead;
+        memset(p, POISON_INUSE, best->size - 1);
+        *((char *)p + best->size - 1) = POISON_END;
+out:
+        spin_unlock(&dap_lock);
+        return p;
+}
+
+void debug_kfree(void *p)
+{
+        struct debug_alloc_header *h;
+        unsigned int h_offset;
+        if (!p)
+                return;
+        if ((char *)p < debug_alloc_pool ||
+            (char *)p >= debug_alloc_pool + sizeof(debug_alloc_pool_aligned)) {
+                kfree(p);
+                return;
+        }
+        if (!get_dap_lock()) {
+                __release(dap_lock);    /* we never actually got it */
+                return;         /* memory leak, cannot be helped */
+        }
+        h = (struct debug_alloc_header *)((char *)p - dah_overhead);
+        memset(p, POISON_FREE, h->size - 1);
+        *((char *)p + h->size - 1) = POISON_END;
+        h->caller = NULL;
+        dah_used -= h->size;
+        h_offset = (char *)h - debug_alloc_pool;
+        if (h_offset < dah_first) {
+                h->next = dah_first;
+                dah_first = h_offset;
+        } else {
+                struct debug_alloc_header *prev;
+                unsigned int prev_offset;
+                prev = (struct debug_alloc_header *)(debug_alloc_pool +
+                                                     dah_first);
+                while (1) {
+                        if (!prev->next || prev->next > h_offset)
+                                break;
+                        prev = (struct debug_alloc_header *)
+                                (debug_alloc_pool + prev->next);
+                }
+                prev_offset = (char *)prev - debug_alloc_pool;
+                if (prev_offset + dah_overhead + prev->size == h_offset) {
+                        prev->size += dah_overhead + h->size;
+                        memset(h, POISON_FREE, dah_overhead - 1);
+                        *((char *)h + dah_overhead - 1) = POISON_END;
+                        h = prev;
+                        h_offset = prev_offset;
+                } else {
+                        h->next = prev->next;
+                        prev->next = h_offset;
+                }
+        }
+        if (h_offset + dah_overhead + h->size == h->next) {
+                struct debug_alloc_header *next;
+                next = (struct debug_alloc_header *)
+                        (debug_alloc_pool + h->next);
+                h->size += dah_overhead + next->size;
+                h->next = next->next;
+                memset(next, POISON_FREE, dah_overhead - 1);
+                *((char *)next + dah_overhead - 1) = POISON_END;
+        }
+        spin_unlock(&dap_lock);
+}
+
+void debug_kusage(void)
+{
+        struct debug_alloc_header *h_free, *h_used;
+#ifdef  CONFIG_IA64
+        /* FIXME: using dah for ia64 unwind always results in a memory leak.
+         * Fix that memory leak first, then set debug_kusage_one_time = 1 for
+         * all architectures.
+         */
+        static int debug_kusage_one_time;
+#else
+        static int debug_kusage_one_time = 1;
+#endif
+        if (!get_dap_lock()) {
+                __release(dap_lock);    /* we never actually got it */
+                return;
+        }
+        h_free = (struct debug_alloc_header *)(debug_alloc_pool + dah_first);
+        if (dah_first == 0 &&
+            (h_free->size == sizeof(debug_alloc_pool_aligned) - dah_overhead ||
+             dah_first_call))
+                goto out;
+        if (!debug_kusage_one_time)
+                goto out;
+        debug_kusage_one_time = 0;
+        kdb_printf("%s: debug_kmalloc memory leak dah_first %d\n",
+                   __func__, dah_first);
+        if (dah_first) {
+                h_used = (struct debug_alloc_header *)debug_alloc_pool;
+                kdb_printf("%s: h_used %p size %d\n", __func__, h_used,
+                           h_used->size);
+        }
+        do {
+                h_used = (struct debug_alloc_header *)
+                          ((char *)h_free + dah_overhead + h_free->size);
+                kdb_printf("%s: h_used %p size %d caller %p\n",
+                           __func__, h_used, h_used->size, h_used->caller);
+                h_free = (struct debug_alloc_header *)
+                          (debug_alloc_pool + h_free->next);
+        } while (h_free->next);
+        h_used = (struct debug_alloc_header *)
+                  ((char *)h_free + dah_overhead + h_free->size);
+        if ((char *)h_used - debug_alloc_pool !=
+            sizeof(debug_alloc_pool_aligned))
+                kdb_printf("%s: h_used %p size %d caller %p\n",
+                           __func__, h_used, h_used->size, h_used->caller);
+out:
+        spin_unlock(&dap_lock);
+}
+
+/* Maintain a small stack of kdb_flags to allow recursion without disturbing
+ * the global kdb state.
+ */
+
+static int kdb_flags_stack[4], kdb_flags_index;
+
+void kdb_save_flags(void)
+{
+        BUG_ON(kdb_flags_index >= ARRAY_SIZE(kdb_flags_stack));
+        kdb_flags_stack[kdb_flags_index++] = kdb_flags;
+}
+
+void kdb_restore_flags(void)
+{
+        BUG_ON(kdb_flags_index <= 0);
+        kdb_flags = kdb_flags_stack[--kdb_flags_index];
+}
diff --git a/kernel/exit.c b/kernel/exit.c
index 7f2683a10ac4..ceffc67b564a 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -55,15 +55,14 @@
 #include <asm/unistd.h>
 #include <asm/pgtable.h>
 #include <asm/mmu_context.h>
-#include "cred-internals.h"
 
 static void exit_mm(struct task_struct * tsk);
 
-static void __unhash_process(struct task_struct *p)
+static void __unhash_process(struct task_struct *p, bool group_dead)
 {
         nr_threads--;
         detach_pid(p, PIDTYPE_PID);
-        if (thread_group_leader(p)) {
+        if (group_dead) {
                 detach_pid(p, PIDTYPE_PGID);
                 detach_pid(p, PIDTYPE_SID);
 
@@ -80,10 +79,9 @@ static void __unhash_process(struct task_struct *p)
 static void __exit_signal(struct task_struct *tsk)
 {
         struct signal_struct *sig = tsk->signal;
+        bool group_dead = thread_group_leader(tsk);
         struct sighand_struct *sighand;
-
-        BUG_ON(!sig);
-        BUG_ON(!atomic_read(&sig->count));
+        struct tty_struct *uninitialized_var(tty);
 
         sighand = rcu_dereference_check(tsk->sighand,
                                         rcu_read_lock_held() ||
@@ -91,14 +89,16 @@ static void __exit_signal(struct task_struct *tsk)
         spin_lock(&sighand->siglock);
 
         posix_cpu_timers_exit(tsk);
-        if (atomic_dec_and_test(&sig->count))
+        if (group_dead) {
                 posix_cpu_timers_exit_group(tsk);
-        else {
+                tty = sig->tty;
+                sig->tty = NULL;
+        } else {
                 /*
                  * If there is any task waiting for the group exit
                  * then notify it:
                  */
-                if (sig->group_exit_task && atomic_read(&sig->count) == sig->notify_count)
+                if (sig->notify_count > 0 && !--sig->notify_count)
                         wake_up_process(sig->group_exit_task);
 
                 if (tsk == sig->curr_target)
@@ -124,32 +124,24 @@ static void __exit_signal(struct task_struct *tsk)
                 sig->oublock += task_io_get_oublock(tsk);
                 task_io_accounting_add(&sig->ioac, &tsk->ioac);
                 sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
-                sig = NULL; /* Marker for below. */
         }
 
-        __unhash_process(tsk);
+        sig->nr_threads--;
+        __unhash_process(tsk, group_dead);
 
         /*
          * Do this under ->siglock, we can race with another thread
          * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
          */
         flush_sigqueue(&tsk->pending);
-
-        tsk->signal = NULL;
         tsk->sighand = NULL;
         spin_unlock(&sighand->siglock);
 
         __cleanup_sighand(sighand);
         clear_tsk_thread_flag(tsk,TIF_SIGPENDING);
-        if (sig) {
+        if (group_dead) {
                 flush_sigqueue(&sig->shared_pending);
-                taskstats_tgid_free(sig);
-                /*
-                 * Make sure ->signal can't go away under rq->lock,
-                 * see account_group_exec_runtime().
-                 */
-                task_rq_unlock_wait(tsk);
-                __cleanup_signal(sig);
+                tty_kref_put(tty);
         }
 }
 
@@ -857,12 +849,9 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
 
         tsk->exit_state = signal == DEATH_REAP ? EXIT_DEAD : EXIT_ZOMBIE;
 
-        /* mt-exec, de_thread() is waiting for us */
-        if (thread_group_leader(tsk) &&
-            tsk->signal->group_exit_task &&
-            tsk->signal->notify_count < 0)
+        /* mt-exec, de_thread() is waiting for group leader */
+        if (unlikely(tsk->signal->notify_count < 0))
                 wake_up_process(tsk->signal->group_exit_task);
-
         write_unlock_irq(&tasklist_lock);
 
         tracehook_report_death(tsk, signal, cookie, group_dead);
@@ -1003,8 +992,10 @@ NORET_TYPE void do_exit(long code)
 
         exit_notify(tsk, group_dead);
 #ifdef CONFIG_NUMA
+        task_lock(tsk);
         mpol_put(tsk->mempolicy);
         tsk->mempolicy = NULL;
+        task_unlock(tsk);
 #endif
 #ifdef CONFIG_FUTEX
         if (unlikely(current->pi_state_cache))
diff --git a/kernel/fork.c b/kernel/fork.c
index 4c14942a0ee3..bf9fef6d1bfe 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -165,6 +165,18 @@ void free_task(struct task_struct *tsk)
 }
 EXPORT_SYMBOL(free_task);
 
+static inline void free_signal_struct(struct signal_struct *sig)
+{
+        taskstats_tgid_free(sig);
+        kmem_cache_free(signal_cachep, sig);
+}
+
+static inline void put_signal_struct(struct signal_struct *sig)
+{
+        if (atomic_dec_and_test(&sig->sigcnt))
+                free_signal_struct(sig);
+}
+
 void __put_task_struct(struct task_struct *tsk)
 {
         WARN_ON(!tsk->exit_state);
@@ -173,6 +185,7 @@ void __put_task_struct(struct task_struct *tsk)
 
         exit_creds(tsk);
         delayacct_tsk_free(tsk);
+        put_signal_struct(tsk->signal);
 
         if (!profile_handoff_task(tsk))
                 free_task(tsk);
@@ -864,8 +877,9 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
         if (!sig)
                 return -ENOMEM;
 
-        atomic_set(&sig->count, 1);
+        sig->nr_threads = 1;
         atomic_set(&sig->live, 1);
+        atomic_set(&sig->sigcnt, 1);
         init_waitqueue_head(&sig->wait_chldexit);
         if (clone_flags & CLONE_NEWPID)
                 sig->flags |= SIGNAL_UNKILLABLE;
@@ -889,13 +903,6 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
         return 0;
 }
 
-void __cleanup_signal(struct signal_struct *sig)
-{
-        thread_group_cputime_free(sig);
-        tty_kref_put(sig->tty);
-        kmem_cache_free(signal_cachep, sig);
-}
-
 static void copy_flags(unsigned long clone_flags, struct task_struct *p)
 {
         unsigned long new_flags = p->flags;
@@ -1079,6 +1086,10 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         }
         mpol_fix_fork_child_flag(p);
 #endif
+#ifdef CONFIG_CPUSETS
+        p->cpuset_mem_spread_rotor = node_random(p->mems_allowed);
+        p->cpuset_slab_spread_rotor = node_random(p->mems_allowed);
+#endif
 #ifdef CONFIG_TRACE_IRQFLAGS
         p->irq_events = 0;
 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
@@ -1112,8 +1123,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         p->memcg_batch.memcg = NULL;
 #endif
 
-        p->bts = NULL;
-
         /* Perform scheduler related setup. Assign this task to a CPU. */
         sched_fork(p, clone_flags);
 
@@ -1247,8 +1256,9 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         }
 
         if (clone_flags & CLONE_THREAD) {
-                atomic_inc(&current->signal->count);
+                current->signal->nr_threads++;
                 atomic_inc(&current->signal->live);
+                atomic_inc(&current->signal->sigcnt);
                 p->group_leader = current->group_leader;
                 list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group);
         }
@@ -1261,7 +1271,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                                 p->nsproxy->pid_ns->child_reaper = p;
 
                         p->signal->leader_pid = pid;
-                        tty_kref_put(p->signal->tty);
                         p->signal->tty = tty_kref_get(current->signal->tty);
                         attach_pid(p, PIDTYPE_PGID, task_pgrp(current));
                         attach_pid(p, PIDTYPE_SID, task_session(current));
@@ -1294,7 +1303,7 @@ bad_fork_cleanup_mm:
                 mmput(p->mm);
 bad_fork_cleanup_signal:
         if (!(clone_flags & CLONE_THREAD))
-                __cleanup_signal(p->signal);
+                free_signal_struct(p->signal);
 bad_fork_cleanup_sighand:
         __cleanup_sighand(p->sighand);
 bad_fork_cleanup_fs:
@@ -1329,6 +1338,16 @@ noinline struct pt_regs * __cpuinit __attribute__((weak)) idle_regs(struct pt_re
         return regs;
 }
 
+static inline void init_idle_pids(struct pid_link *links)
+{
+        enum pid_type type;
+
+        for (type = PIDTYPE_PID; type < PIDTYPE_MAX; ++type) {
+                INIT_HLIST_NODE(&links[type].node); /* not really needed */
+                links[type].pid = &init_struct_pid;
+        }
+}
+
 struct task_struct * __cpuinit fork_idle(int cpu)
 {
         struct task_struct *task;
@@ -1336,8 +1355,10 @@ struct task_struct * __cpuinit fork_idle(int cpu)
 
         task = copy_process(CLONE_VM, 0, idle_regs(&regs), 0, NULL,
                             &init_struct_pid, 0);
-        if (!IS_ERR(task))
+        if (!IS_ERR(task)) {
+                init_idle_pids(task->pids);
                 init_idle(task, cpu);
+        }
 
         return task;
 }
@@ -1509,14 +1530,6 @@ static void check_unshare_flags(unsigned long *flags_ptr)
                 *flags_ptr |= CLONE_SIGHAND;
 
         /*
-         * If unsharing signal handlers and the task was created
-         * using CLONE_THREAD, then must unshare the thread
-         */
-        if ((*flags_ptr & CLONE_SIGHAND) &&
-            (atomic_read(&current->signal->count) > 1))
-                *flags_ptr |= CLONE_THREAD;
-
-        /*
          * If unsharing namespace, must also unshare filesystem information.
          */
         if (*flags_ptr & CLONE_NEWNS)
diff --git a/kernel/groups.c b/kernel/groups.c
index 2b45b2ee3964..53b1916c9492 100644
--- a/kernel/groups.c
+++ b/kernel/groups.c
@@ -164,12 +164,6 @@ int groups_search(const struct group_info *group_info, gid_t grp)
  */
 int set_groups(struct cred *new, struct group_info *group_info)
 {
-        int retval;
-
-        retval = security_task_setgroups(group_info);
-        if (retval)
-                return retval;
-
         put_group_info(new->group_info);
         groups_sort(group_info);
         get_group_info(group_info);
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 0086628b6e97..b9b134b35088 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1749,35 +1749,15 @@ void __init hrtimers_init(void)
 }
 
 /**
- * schedule_hrtimeout_range - sleep until timeout
+ * schedule_hrtimeout_range_clock - sleep until timeout
  * @expires:    timeout value (ktime_t)
  * @delta:      slack in expires timeout (ktime_t)
  * @mode:       timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
- *
- * Make the current task sleep until the given expiry time has
- * elapsed. The routine will return immediately unless
- * the current task state has been set (see set_current_state()).
- *
- * The @delta argument gives the kernel the freedom to schedule the
- * actual wakeup to a time that is both power and performance friendly.
- * The kernel give the normal best effort behavior for "@expires+@delta",
- * but may decide to fire the timer earlier, but no earlier than @expires.
- *
- * You can set the task state as follows -
- *
- * %TASK_UNINTERRUPTIBLE - at least @timeout time is guaranteed to
- * pass before the routine returns.
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task.
- *
- * The current task state is guaranteed to be TASK_RUNNING when this
- * routine returns.
- *
- * Returns 0 when the timer has expired otherwise -EINTR
+ * @clock:      timer clock, CLOCK_MONOTONIC or CLOCK_REALTIME
  */
-int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
-                               const enum hrtimer_mode mode)
+int __sched
+schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
+                               const enum hrtimer_mode mode, int clock)
 {
         struct hrtimer_sleeper t;
 
@@ -1799,7 +1779,7 @@ int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
                 return -EINTR;
         }
 
-        hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, mode);
+        hrtimer_init_on_stack(&t.timer, clock, mode);
         hrtimer_set_expires_range_ns(&t.timer, *expires, delta);
 
         hrtimer_init_sleeper(&t, current);
@@ -1818,6 +1798,41 @@ int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
 
         return !t.task ? 0 : -EINTR;
 }
+
+/**
+ * schedule_hrtimeout_range - sleep until timeout
+ * @expires:    timeout value (ktime_t)
+ * @delta:      slack in expires timeout (ktime_t)
+ * @mode:       timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
+ *
+ * Make the current task sleep until the given expiry time has
+ * elapsed. The routine will return immediately unless
+ * the current task state has been set (see set_current_state()).
+ *
+ * The @delta argument gives the kernel the freedom to schedule the
+ * actual wakeup to a time that is both power and performance friendly.
+ * The kernel give the normal best effort behavior for "@expires+@delta",
+ * but may decide to fire the timer earlier, but no earlier than @expires.
+ *
+ * You can set the task state as follows -
+ *
+ * %TASK_UNINTERRUPTIBLE - at least @timeout time is guaranteed to
+ * pass before the routine returns.
+ *
+ * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
+ * delivered to the current task.
+ *
+ * The current task state is guaranteed to be TASK_RUNNING when this
+ * routine returns.
+ *
+ * Returns 0 when the timer has expired otherwise -EINTR
+ */
+int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
+                                     const enum hrtimer_mode mode)
+{
+        return schedule_hrtimeout_range_clock(expires, delta, mode,
+                                              CLOCK_MONOTONIC);
+}
 EXPORT_SYMBOL_GPL(schedule_hrtimeout_range);
 
 /**
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index 03808ed342a6..7a56b22e0602 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -40,23 +40,29 @@
 #include <linux/percpu.h>
 #include <linux/sched.h>
 #include <linux/init.h>
+#include <linux/slab.h>
 #include <linux/cpu.h>
 #include <linux/smp.h>
 
 #include <linux/hw_breakpoint.h>
 
+
 /*
  * Constraints data
  */
 
 /* Number of pinned cpu breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_cpu_bp_pinned);
+static DEFINE_PER_CPU(unsigned int, nr_cpu_bp_pinned[TYPE_MAX]);
 
 /* Number of pinned task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_task_bp_pinned[HBP_NUM]);
+static DEFINE_PER_CPU(unsigned int *, nr_task_bp_pinned[TYPE_MAX]);
 
 /* Number of non-pinned cpu/task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_bp_flexible);
+static DEFINE_PER_CPU(unsigned int, nr_bp_flexible[TYPE_MAX]);
+
+static int nr_slots[TYPE_MAX];
+
+static int constraints_initialized;
 
 /* Gather the number of total pinned and un-pinned bp in a cpuset */
 struct bp_busy_slots {
@@ -67,16 +73,29 @@ struct bp_busy_slots {
 /* Serialize accesses to the above constraints */
 static DEFINE_MUTEX(nr_bp_mutex);
 
+__weak int hw_breakpoint_weight(struct perf_event *bp)
+{
+        return 1;
+}
+
+static inline enum bp_type_idx find_slot_idx(struct perf_event *bp)
+{
+        if (bp->attr.bp_type & HW_BREAKPOINT_RW)
+                return TYPE_DATA;
+
+        return TYPE_INST;
+}
+
 /*
  * Report the maximum number of pinned breakpoints a task
  * have in this cpu
  */
-static unsigned int max_task_bp_pinned(int cpu)
+static unsigned int max_task_bp_pinned(int cpu, enum bp_type_idx type)
 {
         int i;
-        unsigned int *tsk_pinned = per_cpu(nr_task_bp_pinned, cpu);
+        unsigned int *tsk_pinned = per_cpu(nr_task_bp_pinned[type], cpu);
 
-        for (i = HBP_NUM -1; i >= 0; i--) {
+        for (i = nr_slots[type] - 1; i >= 0; i--) {
                 if (tsk_pinned[i] > 0)
                         return i + 1;
         }
@@ -84,7 +103,7 @@ static unsigned int max_task_bp_pinned(int cpu)
         return 0;
 }
 
-static int task_bp_pinned(struct task_struct *tsk)
+static int task_bp_pinned(struct task_struct *tsk, enum bp_type_idx type)
 {
         struct perf_event_context *ctx = tsk->perf_event_ctxp;
         struct list_head *list;
@@ -105,7 +124,8 @@ static int task_bp_pinned(struct task_struct *tsk)
          */
         list_for_each_entry(bp, list, event_entry) {
                 if (bp->attr.type == PERF_TYPE_BREAKPOINT)
-                        count++;
+                        if (find_slot_idx(bp) == type)
+                                count += hw_breakpoint_weight(bp);
         }
 
         raw_spin_unlock_irqrestore(&ctx->lock, flags);
@@ -118,18 +138,19 @@ static int task_bp_pinned(struct task_struct *tsk)
  * a given cpu (cpu > -1) or in all of them (cpu = -1).
  */
 static void
-fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp)
+fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp,
+                    enum bp_type_idx type)
 {
         int cpu = bp->cpu;
         struct task_struct *tsk = bp->ctx->task;
 
         if (cpu >= 0) {
-                slots->pinned = per_cpu(nr_cpu_bp_pinned, cpu);
+                slots->pinned = per_cpu(nr_cpu_bp_pinned[type], cpu);
                 if (!tsk)
-                        slots->pinned += max_task_bp_pinned(cpu);
+                        slots->pinned += max_task_bp_pinned(cpu, type);
                 else
-                        slots->pinned += task_bp_pinned(tsk);
-                slots->flexible = per_cpu(nr_bp_flexible, cpu);
+                        slots->pinned += task_bp_pinned(tsk, type);
+                slots->flexible = per_cpu(nr_bp_flexible[type], cpu);
 
                 return;
         }
@@ -137,16 +158,16 @@ fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp)
         for_each_online_cpu(cpu) {
                 unsigned int nr;
 
-                nr = per_cpu(nr_cpu_bp_pinned, cpu);
+                nr = per_cpu(nr_cpu_bp_pinned[type], cpu);
                 if (!tsk)
-                        nr += max_task_bp_pinned(cpu);
+                        nr += max_task_bp_pinned(cpu, type);
                 else
-                        nr += task_bp_pinned(tsk);
+                        nr += task_bp_pinned(tsk, type);
 
                 if (nr > slots->pinned)
                         slots->pinned = nr;
 
-                nr = per_cpu(nr_bp_flexible, cpu);
+                nr = per_cpu(nr_bp_flexible[type], cpu);
 
                 if (nr > slots->flexible)
                         slots->flexible = nr;
@@ -154,31 +175,49 @@ fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp)
 }
 
 /*
+ * For now, continue to consider flexible as pinned, until we can
+ * ensure no flexible event can ever be scheduled before a pinned event
+ * in a same cpu.
+ */
+static void
+fetch_this_slot(struct bp_busy_slots *slots, int weight)
+{
+        slots->pinned += weight;
+}
+
+/*
  * Add a pinned breakpoint for the given task in our constraint table
  */
-static void toggle_bp_task_slot(struct task_struct *tsk, int cpu, bool enable)
+static void toggle_bp_task_slot(struct task_struct *tsk, int cpu, bool enable,
+                                enum bp_type_idx type, int weight)
 {
         unsigned int *tsk_pinned;
-        int count = 0;
+        int old_count = 0;
+        int old_idx = 0;
+        int idx = 0;
 
-        count = task_bp_pinned(tsk);
+        old_count = task_bp_pinned(tsk, type);
+        old_idx = old_count - 1;
+        idx = old_idx + weight;
 
-        tsk_pinned = per_cpu(nr_task_bp_pinned, cpu);
+        tsk_pinned = per_cpu(nr_task_bp_pinned[type], cpu);
         if (enable) {
-                tsk_pinned[count]++;
-                if (count > 0)
-                        tsk_pinned[count-1]--;
+                tsk_pinned[idx]++;
+                if (old_count > 0)
+                        tsk_pinned[old_idx]--;
         } else {
-                tsk_pinned[count]--;
-                if (count > 0)
-                        tsk_pinned[count-1]++;
+                tsk_pinned[idx]--;
+                if (old_count > 0)
+                        tsk_pinned[old_idx]++;
         }
 }
 
 /*
  * Add/remove the given breakpoint in our constraint table
  */
-static void toggle_bp_slot(struct perf_event *bp, bool enable)
+static void
+toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type,
+               int weight)
 {
         int cpu = bp->cpu;
         struct task_struct *tsk = bp->ctx->task;
@@ -186,20 +225,20 @@ static void toggle_bp_slot(struct perf_event *bp, bool enable)
         /* Pinned counter task profiling */
         if (tsk) {
                 if (cpu >= 0) {
-                        toggle_bp_task_slot(tsk, cpu, enable);
+                        toggle_bp_task_slot(tsk, cpu, enable, type, weight);
                         return;
                 }
 
                 for_each_online_cpu(cpu)
-                        toggle_bp_task_slot(tsk, cpu, enable);
+                        toggle_bp_task_slot(tsk, cpu, enable, type, weight);
                 return;
         }
 
         /* Pinned counter cpu profiling */
         if (enable)
-                per_cpu(nr_cpu_bp_pinned, bp->cpu)++;
+                per_cpu(nr_cpu_bp_pinned[type], bp->cpu) += weight;
         else
-                per_cpu(nr_cpu_bp_pinned, bp->cpu)--;
+                per_cpu(nr_cpu_bp_pinned[type], bp->cpu) -= weight;
 }
 
 /*
@@ -246,14 +285,29 @@ static void toggle_bp_slot(struct perf_event *bp, bool enable)
 static int __reserve_bp_slot(struct perf_event *bp)
 {
         struct bp_busy_slots slots = {0};
+        enum bp_type_idx type;
+        int weight;
 
-        fetch_bp_busy_slots(&slots, bp);
+        /* We couldn't initialize breakpoint constraints on boot */
+        if (!constraints_initialized)
+                return -ENOMEM;
+
+        /* Basic checks */
+        if (bp->attr.bp_type == HW_BREAKPOINT_EMPTY ||
+            bp->attr.bp_type == HW_BREAKPOINT_INVALID)
+                return -EINVAL;
+
+        type = find_slot_idx(bp);
+        weight = hw_breakpoint_weight(bp);
+
+        fetch_bp_busy_slots(&slots, bp, type);
+        fetch_this_slot(&slots, weight);
 
         /* Flexible counters need to keep at least one slot */
-        if (slots.pinned + (!!slots.flexible) == HBP_NUM)
+        if (slots.pinned + (!!slots.flexible) > nr_slots[type])
                 return -ENOSPC;
 
-        toggle_bp_slot(bp, true);
+        toggle_bp_slot(bp, true, type, weight);
 
         return 0;
 }
@@ -273,7 +327,12 @@ int reserve_bp_slot(struct perf_event *bp)
 
 static void __release_bp_slot(struct perf_event *bp)
 {
-        toggle_bp_slot(bp, false);
+        enum bp_type_idx type;
+        int weight;
+
+        type = find_slot_idx(bp);
+        weight = hw_breakpoint_weight(bp);
+        toggle_bp_slot(bp, false, type, weight);
 }
 
 void release_bp_slot(struct perf_event *bp)
@@ -308,6 +367,28 @@ int dbg_release_bp_slot(struct perf_event *bp)
         return 0;
 }
 
+static int validate_hw_breakpoint(struct perf_event *bp)
+{
+        int ret;
+
+        ret = arch_validate_hwbkpt_settings(bp);
+        if (ret)
+                return ret;
+
+        if (arch_check_bp_in_kernelspace(bp)) {
+                if (bp->attr.exclude_kernel)
+                        return -EINVAL;
+                /*
+                 * Don't let unprivileged users set a breakpoint in the trap
+                 * path to avoid trap recursion attacks.
+                 */
+                if (!capable(CAP_SYS_ADMIN))
+                        return -EPERM;
+        }
+
+        return 0;
+}
+
 int register_perf_hw_breakpoint(struct perf_event *bp)
 {
         int ret;
@@ -316,17 +397,7 @@ int register_perf_hw_breakpoint(struct perf_event *bp)
         if (ret)
                 return ret;
 
-        /*
-         * Ptrace breakpoints can be temporary perf events only
-         * meant to reserve a slot. In this case, it is created disabled and
-         * we don't want to check the params right now (as we put a null addr)
-         * But perf tools create events as disabled and we want to check
-         * the params for them.
-         * This is a quick hack that will be removed soon, once we remove
-         * the tmp breakpoints from ptrace
-         */
-        if (!bp->attr.disabled || !bp->overflow_handler)
-                ret = arch_validate_hwbkpt_settings(bp, bp->ctx->task);
+        ret = validate_hw_breakpoint(bp);
 
         /* if arch_validate_hwbkpt_settings() fails then release bp slot */
         if (ret)
@@ -373,7 +444,7 @@ int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *att
         if (attr->disabled)
                 goto end;
 
-        err = arch_validate_hwbkpt_settings(bp, bp->ctx->task);
+        err = validate_hw_breakpoint(bp);
         if (!err)
                 perf_event_enable(bp);
 
@@ -480,7 +551,36 @@ static struct notifier_block hw_breakpoint_exceptions_nb = {
 
 static int __init init_hw_breakpoint(void)
 {
+        unsigned int **task_bp_pinned;
+        int cpu, err_cpu;
+        int i;
+
+        for (i = 0; i < TYPE_MAX; i++)
+                nr_slots[i] = hw_breakpoint_slots(i);
+
+        for_each_possible_cpu(cpu) {
+                for (i = 0; i < TYPE_MAX; i++) {
+                        task_bp_pinned = &per_cpu(nr_task_bp_pinned[i], cpu);
+                        *task_bp_pinned = kzalloc(sizeof(int) * nr_slots[i],
+                                                  GFP_KERNEL);
+                        if (!*task_bp_pinned)
+                                goto err_alloc;
+                }
+        }
+
+        constraints_initialized = 1;
+
         return register_die_notifier(&hw_breakpoint_exceptions_nb);
+
+ err_alloc:
+        for_each_possible_cpu(err_cpu) {
+                if (err_cpu == cpu)
+                        break;
+                for (i = 0; i < TYPE_MAX; i++)
+                        kfree(per_cpu(nr_task_bp_pinned[i], cpu));
+        }
+
+        return -ENOMEM;
 }
 core_initcall(init_hw_breakpoint);
 
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 76d5a671bfe1..27e5c6911223 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -370,9 +370,6 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
         irqreturn_t ret, retval = IRQ_NONE;
         unsigned int status = 0;
 
-        if (!(action->flags & IRQF_DISABLED))
-                local_irq_enable_in_hardirq();
-
         do {
                 trace_irq_handler_entry(irq, action);
                 ret = action->handler(irq, action->dev_id);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 704e488730a5..3164ba7ce151 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -138,6 +138,22 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
         return 0;
 }
 
+int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+{
+        struct irq_desc *desc = irq_to_desc(irq);
+        unsigned long flags;
+
+        if (!desc)
+                return -EINVAL;
+
+        raw_spin_lock_irqsave(&desc->lock, flags);
+        desc->affinity_hint = m;
+        raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
+
 #ifndef CONFIG_AUTO_IRQ_AFFINITY
 /*
  * Generic version of the affinity autoselector.
@@ -757,16 +773,6 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                 if (new->flags & IRQF_ONESHOT)
                         desc->status |= IRQ_ONESHOT;
 
-                /*
-                 * Force MSI interrupts to run with interrupts
-                 * disabled. The multi vector cards can cause stack
-                 * overflows due to nested interrupts when enough of
-                 * them are directed to a core and fire at the same
-                 * time.
-                 */
-                if (desc->msi_desc)
-                        new->flags |= IRQF_DISABLED;
-
                 if (!(desc->status & IRQ_NOAUTOEN)) {
                         desc->depth = 0;
                         desc->status &= ~IRQ_DISABLED;
@@ -916,6 +922,12 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
                         desc->chip->disable(irq);
         }
 
+#ifdef CONFIG_SMP
+        /* make sure affinity_hint is cleaned up */
+        if (WARN_ON_ONCE(desc->affinity_hint))
+                desc->affinity_hint = NULL;
+#endif
+
         raw_spin_unlock_irqrestore(&desc->lock, flags);
 
         unregister_handler_proc(irq, action);
@@ -1027,7 +1039,6 @@ EXPORT_SYMBOL(free_irq);
  *      Flags:
  *
  *      IRQF_SHARED             Interrupt is shared
- *      IRQF_DISABLED   Disable local interrupts while processing
  *      IRQF_SAMPLE_RANDOM      The interrupt can be used for entropy
  *      IRQF_TRIGGER_*          Specify active edge(s) or level
  *
@@ -1041,25 +1052,6 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
         int retval;
 
         /*
-         * handle_IRQ_event() always ignores IRQF_DISABLED except for
-         * the _first_ irqaction (sigh).  That can cause oopsing, but
-         * the behavior is classified as "will not fix" so we need to
-         * start nudging drivers away from using that idiom.
-         */
-        if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
-                                        (IRQF_SHARED|IRQF_DISABLED)) {
-                pr_warning(
-                  "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
-                        irq, devname);
-        }
-
-#ifdef CONFIG_LOCKDEP
-        /*
-         * Lockdep wants atomic interrupt handlers:
-         */
-        irqflags |= IRQF_DISABLED;
-#endif
-        /*
          * Sanity-check: shared interrupts must pass in a real dev-ID,
          * otherwise we'll have trouble later trying to figure out
          * which interrupt is which (messes up the interrupt freeing
@@ -1120,3 +1112,40 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
         return retval;
 }
 EXPORT_SYMBOL(request_threaded_irq);
+
+/**
+ *      request_any_context_irq - allocate an interrupt line
+ *      @irq: Interrupt line to allocate
+ *      @handler: Function to be called when the IRQ occurs.
+ *                Threaded handler for threaded interrupts.
+ *      @flags: Interrupt type flags
+ *      @name: An ascii name for the claiming device
+ *      @dev_id: A cookie passed back to the handler function
+ *
+ *      This call allocates interrupt resources and enables the
+ *      interrupt line and IRQ handling. It selects either a
+ *      hardirq or threaded handling method depending on the
+ *      context.
+ *
+ *      On failure, it returns a negative value. On success,
+ *      it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
+ */
+int request_any_context_irq(unsigned int irq, irq_handler_t handler,
+                            unsigned long flags, const char *name, void *dev_id)
+{
+        struct irq_desc *desc = irq_to_desc(irq);
+        int ret;
+
+        if (!desc)
+                return -EINVAL;
+
+        if (desc->status & IRQ_NESTED_THREAD) {
+                ret = request_threaded_irq(irq, NULL, handler,
+                                           flags, name, dev_id);
+                return !ret ? IRQC_IS_NESTED : ret;
+        }
+
+        ret = request_irq(irq, handler, flags, name, dev_id);
+        return !ret ? IRQC_IS_HARDIRQ : ret;
+}
+EXPORT_SYMBOL_GPL(request_any_context_irq);
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 7a6eb04ef6b5..09a2ee540bd2 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -32,6 +32,27 @@ static int irq_affinity_proc_show(struct seq_file *m, void *v)
         return 0;
 }
 
+static int irq_affinity_hint_proc_show(struct seq_file *m, void *v)
+{
+        struct irq_desc *desc = irq_to_desc((long)m->private);
+        unsigned long flags;
+        cpumask_var_t mask;
+
+        if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
+                return -ENOMEM;
+
+        raw_spin_lock_irqsave(&desc->lock, flags);
+        if (desc->affinity_hint)
+                cpumask_copy(mask, desc->affinity_hint);
+        raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+        seq_cpumask(m, mask);
+        seq_putc(m, '\n');
+        free_cpumask_var(mask);
+
+        return 0;
+}
+
 #ifndef is_affinity_mask_valid
 #define is_affinity_mask_valid(val) 1
 #endif
@@ -84,6 +105,11 @@ static int irq_affinity_proc_open(struct inode *inode, struct file *file)
         return single_open(file, irq_affinity_proc_show, PDE(inode)->data);
 }
 
+static int irq_affinity_hint_proc_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, irq_affinity_hint_proc_show, PDE(inode)->data);
+}
+
 static const struct file_operations irq_affinity_proc_fops = {
         .open           = irq_affinity_proc_open,
         .read           = seq_read,
@@ -92,6 +118,13 @@ static const struct file_operations irq_affinity_proc_fops = {
         .write          = irq_affinity_proc_write,
 };
 
+static const struct file_operations irq_affinity_hint_proc_fops = {
+        .open           = irq_affinity_hint_proc_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
 static int default_affinity_show(struct seq_file *m, void *v)
 {
         seq_cpumask(m, irq_default_affinity);
@@ -147,6 +180,26 @@ static const struct file_operations default_affinity_proc_fops = {
         .release        = single_release,
         .write          = default_affinity_write,
 };
+
+static int irq_node_proc_show(struct seq_file *m, void *v)
+{
+        struct irq_desc *desc = irq_to_desc((long) m->private);
+
+        seq_printf(m, "%d\n", desc->node);
+        return 0;
+}
+
+static int irq_node_proc_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, irq_node_proc_show, PDE(inode)->data);
+}
+
+static const struct file_operations irq_node_proc_fops = {
+        .open           = irq_node_proc_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
 #endif
 
 static int irq_spurious_proc_show(struct seq_file *m, void *v)
@@ -231,6 +284,13 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc)
         /* create /proc/irq/<irq>/smp_affinity */
         proc_create_data("smp_affinity", 0600, desc->dir,
                          &irq_affinity_proc_fops, (void *)(long)irq);
+
+        /* create /proc/irq/<irq>/affinity_hint */
+        proc_create_data("affinity_hint", 0400, desc->dir,
+                         &irq_affinity_hint_proc_fops, (void *)(long)irq);
+
+        proc_create_data("node", 0444, desc->dir,
+                         &irq_node_proc_fops, (void *)(long)irq);
 #endif
 
         proc_create_data("spurious", 0444, desc->dir,
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 13aff293f4de..6f6d091b5757 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -16,6 +16,7 @@
 #include <linux/init.h>
 #include <linux/seq_file.h>
 #include <linux/fs.h>
+#include <linux/kdb.h>
 #include <linux/err.h>
 #include <linux/proc_fs.h>
 #include <linux/sched.h>        /* for cond_resched */
@@ -516,6 +517,26 @@ static int kallsyms_open(struct inode *inode, struct file *file)
         return ret;
 }
 
+#ifdef  CONFIG_KGDB_KDB
+const char *kdb_walk_kallsyms(loff_t *pos)
+{
+        static struct kallsym_iter kdb_walk_kallsyms_iter;
+        if (*pos == 0) {
+                memset(&kdb_walk_kallsyms_iter, 0,
+                       sizeof(kdb_walk_kallsyms_iter));
+                reset_iter(&kdb_walk_kallsyms_iter, 0);
+        }
+        while (1) {
+                if (!update_iter(&kdb_walk_kallsyms_iter, *pos))
+                        return NULL;
+                ++*pos;
+                /* Some debugging symbols have no name.  Ignore them. */
+                if (kdb_walk_kallsyms_iter.name[0])
+                        return kdb_walk_kallsyms_iter.name;
+        }
+}
+#endif  /* CONFIG_KGDB_KDB */
+
 static const struct file_operations kallsyms_operations = {
         .open = kallsyms_open,
         .read = seq_read,
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
deleted file mode 100644
index 11f3515ca83f..000000000000
--- a/kernel/kgdb.c
+++ /dev/null
@@ -1,1764 +0,0 @@
-/*
- * KGDB stub.
- *
- * Maintainer: Jason Wessel <jason.wessel@windriver.com>
- *
- * Copyright (C) 2000-2001 VERITAS Software Corporation.
- * Copyright (C) 2002-2004 Timesys Corporation
- * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com>
- * Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
- * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
- * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
- * Copyright (C) 2005-2008 Wind River Systems, Inc.
- * Copyright (C) 2007 MontaVista Software, Inc.
- * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- *
- * Contributors at various stages not listed above:
- *  Jason Wessel ( jason.wessel@windriver.com )
- *  George Anzinger <george@mvista.com>
- *  Anurekh Saxena (anurekh.saxena@timesys.com)
- *  Lake Stevens Instrument Division (Glenn Engel)
- *  Jim Kingdon, Cygnus Support.
- *
- * Original KGDB stub: David Grothe <dave@gcom.com>,
- * Tigran Aivazian <tigran@sco.com>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2. This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
- */
-#include <linux/pid_namespace.h>
-#include <linux/clocksource.h>
-#include <linux/interrupt.h>
-#include <linux/spinlock.h>
-#include <linux/console.h>
-#include <linux/threads.h>
-#include <linux/uaccess.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/ptrace.h>
-#include <linux/reboot.h>
-#include <linux/string.h>
-#include <linux/delay.h>
-#include <linux/sched.h>
-#include <linux/sysrq.h>
-#include <linux/init.h>
-#include <linux/kgdb.h>
-#include <linux/pid.h>
-#include <linux/smp.h>
-#include <linux/mm.h>
-
-#include <asm/cacheflush.h>
-#include <asm/byteorder.h>
-#include <asm/atomic.h>
-#include <asm/system.h>
-#include <asm/unaligned.h>
-
-static int kgdb_break_asap;
-
-#define KGDB_MAX_THREAD_QUERY 17
-struct kgdb_state {
-        int                     ex_vector;
-        int                     signo;
-        int                     err_code;
-        int                     cpu;
-        int                     pass_exception;
-        unsigned long           thr_query;
-        unsigned long           threadid;
-        long                    kgdb_usethreadid;
-        struct pt_regs          *linux_regs;
-};
-
-/* Exception state values */
-#define DCPU_WANT_MASTER 0x1 /* Waiting to become a master kgdb cpu */
-#define DCPU_NEXT_MASTER 0x2 /* Transition from one master cpu to another */
-#define DCPU_IS_SLAVE    0x4 /* Slave cpu enter exception */
-#define DCPU_SSTEP       0x8 /* CPU is single stepping */
-
-static struct debuggerinfo_struct {
-        void                    *debuggerinfo;
-        struct task_struct      *task;
-        int                     exception_state;
-} kgdb_info[NR_CPUS];
-
-/**
- * kgdb_connected - Is a host GDB connected to us?
- */
-int                             kgdb_connected;
-EXPORT_SYMBOL_GPL(kgdb_connected);
-
-/* All the KGDB handlers are installed */
-static int                      kgdb_io_module_registered;
-
-/* Guard for recursive entry */
-static int                      exception_level;
-
-static struct kgdb_io           *kgdb_io_ops;
-static DEFINE_SPINLOCK(kgdb_registration_lock);
-
-/* kgdb console driver is loaded */
-static int kgdb_con_registered;
-/* determine if kgdb console output should be used */
-static int kgdb_use_con;
-
-static int __init opt_kgdb_con(char *str)
-{
-        kgdb_use_con = 1;
-        return 0;
-}
-
-early_param("kgdbcon", opt_kgdb_con);
-
-module_param(kgdb_use_con, int, 0644);
-
-/*
- * Holds information about breakpoints in a kernel. These breakpoints are
- * added and removed by gdb.
- */
-static struct kgdb_bkpt         kgdb_break[KGDB_MAX_BREAKPOINTS] = {
-        [0 ... KGDB_MAX_BREAKPOINTS-1] = { .state = BP_UNDEFINED }
-};
-
-/*
- * The CPU# of the active CPU, or -1 if none:
- */
-atomic_t                        kgdb_active = ATOMIC_INIT(-1);
-
-/*
- * We use NR_CPUs not PERCPU, in case kgdb is used to debug early
- * bootup code (which might not have percpu set up yet):
- */
-static atomic_t                 passive_cpu_wait[NR_CPUS];
-static atomic_t                 cpu_in_kgdb[NR_CPUS];
-atomic_t                        kgdb_setting_breakpoint;
-
-struct task_struct              *kgdb_usethread;
-struct task_struct              *kgdb_contthread;
-
-int                             kgdb_single_step;
-pid_t                           kgdb_sstep_pid;
-
-/* Our I/O buffers. */
-static char                     remcom_in_buffer[BUFMAX];
-static char                     remcom_out_buffer[BUFMAX];
-
-/* Storage for the registers, in GDB format. */
-static unsigned long            gdb_regs[(NUMREGBYTES +
-                                        sizeof(unsigned long) - 1) /
-                                        sizeof(unsigned long)];
-
-/* to keep track of the CPU which is doing the single stepping*/
-atomic_t                        kgdb_cpu_doing_single_step = ATOMIC_INIT(-1);
-
-/*
- * If you are debugging a problem where roundup (the collection of
- * all other CPUs) is a problem [this should be extremely rare],
- * then use the nokgdbroundup option to avoid roundup. In that case
- * the other CPUs might interfere with your debugging context, so
- * use this with care:
- */
-static int kgdb_do_roundup = 1;
-
-static int __init opt_nokgdbroundup(char *str)
-{
-        kgdb_do_roundup = 0;
-
-        return 0;
-}
-
-early_param("nokgdbroundup", opt_nokgdbroundup);
-
-/*
- * Finally, some KGDB code :-)
- */
-
-/*
- * Weak aliases for breakpoint management,
- * can be overriden by architectures when needed:
- */
-int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr)
-{
-        int err;
-
-        err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE);
-        if (err)
-                return err;
-
-        return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr,
-                                  BREAK_INSTR_SIZE);
-}
-
-int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle)
-{
-        return probe_kernel_write((char *)addr,
-                                  (char *)bundle, BREAK_INSTR_SIZE);
-}
-
-int __weak kgdb_validate_break_address(unsigned long addr)
-{
-        char tmp_variable[BREAK_INSTR_SIZE];
-        int err;
-        /* Validate setting the breakpoint and then removing it.  In the
-         * remove fails, the kernel needs to emit a bad message because we
-         * are deep trouble not being able to put things back the way we
-         * found them.
-         */
-        err = kgdb_arch_set_breakpoint(addr, tmp_variable);
-        if (err)
-                return err;
-        err = kgdb_arch_remove_breakpoint(addr, tmp_variable);
-        if (err)
-                printk(KERN_ERR "KGDB: Critical breakpoint error, kernel "
-                   "memory destroyed at: %lx", addr);
-        return err;
-}
-
-unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs)
-{
-        return instruction_pointer(regs);
-}
-
-int __weak kgdb_arch_init(void)
-{
-        return 0;
-}
-
-int __weak kgdb_skipexception(int exception, struct pt_regs *regs)
-{
-        return 0;
-}
-
-void __weak
-kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code)
-{
-        return;
-}
-
-/**
- *      kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
- *      @regs: Current &struct pt_regs.
- *
- *      This function will be called if the particular architecture must
- *      disable hardware debugging while it is processing gdb packets or
- *      handling exception.
- */
-void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
-{
-}
-
-/*
- * GDB remote protocol parser:
- */
-
-static int hex(char ch)
-{
-        if ((ch >= 'a') && (ch <= 'f'))
-                return ch - 'a' + 10;
-        if ((ch >= '0') && (ch <= '9'))
-                return ch - '0';
-        if ((ch >= 'A') && (ch <= 'F'))
-                return ch - 'A' + 10;
-        return -1;
-}
-
-/* scan for the sequence $<data>#<checksum> */
-static void get_packet(char *buffer)
-{
-        unsigned char checksum;
-        unsigned char xmitcsum;
-        int count;
-        char ch;
-
-        do {
-                /*
-                 * Spin and wait around for the start character, ignore all
-                 * other characters:
-                 */
-                while ((ch = (kgdb_io_ops->read_char())) != '$')
-                        /* nothing */;
-
-                kgdb_connected = 1;
-                checksum = 0;
-                xmitcsum = -1;
-
-                count = 0;
-
-                /*
-                 * now, read until a # or end of buffer is found:
-                 */
-                while (count < (BUFMAX - 1)) {
-                        ch = kgdb_io_ops->read_char();
-                        if (ch == '#')
-                                break;
-                        checksum = checksum + ch;
-                        buffer[count] = ch;
-                        count = count + 1;
-                }
-                buffer[count] = 0;
-
-                if (ch == '#') {
-                        xmitcsum = hex(kgdb_io_ops->read_char()) << 4;
-                        xmitcsum += hex(kgdb_io_ops->read_char());
-
-                        if (checksum != xmitcsum)
-                                /* failed checksum */
-                                kgdb_io_ops->write_char('-');
-                        else
-                                /* successful transfer */
-                                kgdb_io_ops->write_char('+');
-                        if (kgdb_io_ops->flush)
-                                kgdb_io_ops->flush();
-                }
-        } while (checksum != xmitcsum);
-}
-
-/*
- * Send the packet in buffer.
- * Check for gdb connection if asked for.
- */
-static void put_packet(char *buffer)
-{
-        unsigned char checksum;
-        int count;
-        char ch;
-
-        /*
-         * $<packet info>#<checksum>.
-         */
-        while (1) {
-                kgdb_io_ops->write_char('$');
-                checksum = 0;
-                count = 0;
-
-                while ((ch = buffer[count])) {
-                        kgdb_io_ops->write_char(ch);
-                        checksum += ch;
-                        count++;
-                }
-
-                kgdb_io_ops->write_char('#');
-                kgdb_io_ops->write_char(hex_asc_hi(checksum));
-                kgdb_io_ops->write_char(hex_asc_lo(checksum));
-                if (kgdb_io_ops->flush)
-                        kgdb_io_ops->flush();
-
-                /* Now see what we get in reply. */
-                ch = kgdb_io_ops->read_char();
-
-                if (ch == 3)
-                        ch = kgdb_io_ops->read_char();
-
-                /* If we get an ACK, we are done. */
-                if (ch == '+')
-                        return;
-
-                /*
-                 * If we get the start of another packet, this means
-                 * that GDB is attempting to reconnect.  We will NAK
-                 * the packet being sent, and stop trying to send this
-                 * packet.
-                 */
-                if (ch == '$') {
-                        kgdb_io_ops->write_char('-');
-                        if (kgdb_io_ops->flush)
-                                kgdb_io_ops->flush();
-                        return;
-                }
-        }
-}
-
-/*
- * Convert the memory pointed to by mem into hex, placing result in buf.
- * Return a pointer to the last char put in buf (null). May return an error.
- */
-int kgdb_mem2hex(char *mem, char *buf, int count)
-{
-        char *tmp;
-        int err;
-
-        /*
-         * We use the upper half of buf as an intermediate buffer for the
-         * raw memory copy.  Hex conversion will work against this one.
-         */
-        tmp = buf + count;
-
-        err = probe_kernel_read(tmp, mem, count);
-        if (!err) {
-                while (count > 0) {
-                        buf = pack_hex_byte(buf, *tmp);
-                        tmp++;
-                        count--;
-                }
-
-                *buf = 0;
-        }
-
-        return err;
-}
-
-/*
- * Copy the binary array pointed to by buf into mem.  Fix $, #, and
- * 0x7d escaped with 0x7d. Return -EFAULT on failure or 0 on success.
- * The input buf is overwitten with the result to write to mem.
- */
-static int kgdb_ebin2mem(char *buf, char *mem, int count)
-{
-        int size = 0;
-        char *c = buf;
-
-        while (count-- > 0) {
-                c[size] = *buf++;
-                if (c[size] == 0x7d)
-                        c[size] = *buf++ ^ 0x20;
-                size++;
-        }
-
-        return probe_kernel_write(mem, c, size);
-}
-
-/*
- * Convert the hex array pointed to by buf into binary to be placed in mem.
- * Return a pointer to the character AFTER the last byte written.
- * May return an error.
- */
-int kgdb_hex2mem(char *buf, char *mem, int count)
-{
-        char *tmp_raw;
-        char *tmp_hex;
-
-        /*
-         * We use the upper half of buf as an intermediate buffer for the
-         * raw memory that is converted from hex.
-         */
-        tmp_raw = buf + count * 2;
-
-        tmp_hex = tmp_raw - 1;
-        while (tmp_hex >= buf) {
-                tmp_raw--;
-                *tmp_raw = hex(*tmp_hex--);
-                *tmp_raw |= hex(*tmp_hex--) << 4;
-        }
-
-        return probe_kernel_write(mem, tmp_raw, count);
-}
-
-/*
- * While we find nice hex chars, build a long_val.
- * Return number of chars processed.
- */
-int kgdb_hex2long(char **ptr, unsigned long *long_val)
-{
-        int hex_val;
-        int num = 0;
-        int negate = 0;
-
-        *long_val = 0;
-
-        if (**ptr == '-') {
-                negate = 1;
-                (*ptr)++;
-        }
-        while (**ptr) {
-                hex_val = hex(**ptr);
-                if (hex_val < 0)
-                        break;
-
-                *long_val = (*long_val << 4) | hex_val;
-                num++;
-                (*ptr)++;
-        }
-
-        if (negate)
-                *long_val = -*long_val;
-
-        return num;
-}
-
-/* Write memory due to an 'M' or 'X' packet. */
-static int write_mem_msg(int binary)
-{
-        char *ptr = &remcom_in_buffer[1];
-        unsigned long addr;
-        unsigned long length;
-        int err;
-
-        if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' &&
-            kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') {
-                if (binary)
-                        err = kgdb_ebin2mem(ptr, (char *)addr, length);
-                else
-                        err = kgdb_hex2mem(ptr, (char *)addr, length);
-                if (err)
-                        return err;
-                if (CACHE_FLUSH_IS_SAFE)
-                        flush_icache_range(addr, addr + length);
-                return 0;
-        }
-
-        return -EINVAL;
-}
-
-static void error_packet(char *pkt, int error)
-{
-        error = -error;
-        pkt[0] = 'E';
-        pkt[1] = hex_asc[(error / 10)];
-        pkt[2] = hex_asc[(error % 10)];
-        pkt[3] = '\0';
-}
-
-/*
- * Thread ID accessors. We represent a flat TID space to GDB, where
- * the per CPU idle threads (which under Linux all have PID 0) are
- * remapped to negative TIDs.
- */
-
-#define BUF_THREAD_ID_SIZE      16
-
-static char *pack_threadid(char *pkt, unsigned char *id)
-{
-        char *limit;
-
-        limit = pkt + BUF_THREAD_ID_SIZE;
-        while (pkt < limit)
-                pkt = pack_hex_byte(pkt, *id++);
-
-        return pkt;
-}
-
-static void int_to_threadref(unsigned char *id, int value)
-{
-        unsigned char *scan;
-        int i = 4;
-
-        scan = (unsigned char *)id;
-        while (i--)
-                *scan++ = 0;
-        put_unaligned_be32(value, scan);
-}
-
-static struct task_struct *getthread(struct pt_regs *regs, int tid)
-{
-        /*
-         * Non-positive TIDs are remapped to the cpu shadow information
-         */
-        if (tid == 0 || tid == -1)
-                tid = -atomic_read(&kgdb_active) - 2;
-        if (tid < -1 && tid > -NR_CPUS - 2) {
-                if (kgdb_info[-tid - 2].task)
-                        return kgdb_info[-tid - 2].task;
-                else
-                        return idle_task(-tid - 2);
-        }
-        if (tid <= 0) {
-                printk(KERN_ERR "KGDB: Internal thread select error\n");
-                dump_stack();
-                return NULL;
-        }
-
-        /*
-         * find_task_by_pid_ns() does not take the tasklist lock anymore
-         * but is nicely RCU locked - hence is a pretty resilient
-         * thing to use:
-         */
-        return find_task_by_pid_ns(tid, &init_pid_ns);
-}
-
-/*
- * Some architectures need cache flushes when we set/clear a
- * breakpoint:
- */
-static void kgdb_flush_swbreak_addr(unsigned long addr)
-{
-        if (!CACHE_FLUSH_IS_SAFE)
-                return;
-
-        if (current->mm && current->mm->mmap_cache) {
-                flush_cache_range(current->mm->mmap_cache,
-                                  addr, addr + BREAK_INSTR_SIZE);
-        }
-        /* Force flush instruction cache if it was outside the mm */
-        flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
-}
-
-/*
- * SW breakpoint management:
- */
-static int kgdb_activate_sw_breakpoints(void)
-{
-        unsigned long addr;
-        int error;
-        int ret = 0;
-        int i;
-
-        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                if (kgdb_break[i].state != BP_SET)
-                        continue;
-
-                addr = kgdb_break[i].bpt_addr;
-                error = kgdb_arch_set_breakpoint(addr,
-                                kgdb_break[i].saved_instr);
-                if (error) {
-                        ret = error;
-                        printk(KERN_INFO "KGDB: BP install failed: %lx", addr);
-                        continue;
-                }
-
-                kgdb_flush_swbreak_addr(addr);
-                kgdb_break[i].state = BP_ACTIVE;
-        }
-        return ret;
-}
-
-static int kgdb_set_sw_break(unsigned long addr)
-{
-        int err = kgdb_validate_break_address(addr);
-        int breakno = -1;
-        int i;
-
-        if (err)
-                return err;
-
-        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                if ((kgdb_break[i].state == BP_SET) &&
-                                        (kgdb_break[i].bpt_addr == addr))
-                        return -EEXIST;
-        }
-        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                if (kgdb_break[i].state == BP_REMOVED &&
-                                        kgdb_break[i].bpt_addr == addr) {
-                        breakno = i;
-                        break;
-                }
-        }
-
-        if (breakno == -1) {
-                for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                        if (kgdb_break[i].state == BP_UNDEFINED) {
-                                breakno = i;
-                                break;
-                        }
-                }
-        }
-
-        if (breakno == -1)
-                return -E2BIG;
-
-        kgdb_break[breakno].state = BP_SET;
-        kgdb_break[breakno].type = BP_BREAKPOINT;
-        kgdb_break[breakno].bpt_addr = addr;
-
-        return 0;
-}
-
-static int kgdb_deactivate_sw_breakpoints(void)
-{
-        unsigned long addr;
-        int error;
-        int ret = 0;
-        int i;
-
-        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                if (kgdb_break[i].state != BP_ACTIVE)
-                        continue;
-                addr = kgdb_break[i].bpt_addr;
-                error = kgdb_arch_remove_breakpoint(addr,
-                                        kgdb_break[i].saved_instr);
-                if (error) {
-                        printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr);
-                        ret = error;
-                }
-
-                kgdb_flush_swbreak_addr(addr);
-                kgdb_break[i].state = BP_SET;
-        }
-        return ret;
-}
-
-static int kgdb_remove_sw_break(unsigned long addr)
-{
-        int i;
-
-        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                if ((kgdb_break[i].state == BP_SET) &&
-                                (kgdb_break[i].bpt_addr == addr)) {
-                        kgdb_break[i].state = BP_REMOVED;
-                        return 0;
-                }
-        }
-        return -ENOENT;
-}
-
-int kgdb_isremovedbreak(unsigned long addr)
-{
-        int i;
-
-        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                if ((kgdb_break[i].state == BP_REMOVED) &&
-                                        (kgdb_break[i].bpt_addr == addr))
-                        return 1;
-        }
-        return 0;
-}
-
-static int remove_all_break(void)
-{
-        unsigned long addr;
-        int error;
-        int i;
-
-        /* Clear memory breakpoints. */
-        for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
-                if (kgdb_break[i].state != BP_ACTIVE)
-                        goto setundefined;
-                addr = kgdb_break[i].bpt_addr;
-                error = kgdb_arch_remove_breakpoint(addr,
-                                kgdb_break[i].saved_instr);
-                if (error)
-                        printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n",
-                           addr);
-setundefined:
-                kgdb_break[i].state = BP_UNDEFINED;
-        }
-
-        /* Clear hardware breakpoints. */
-        if (arch_kgdb_ops.remove_all_hw_break)
-                arch_kgdb_ops.remove_all_hw_break();
-
-        return 0;
-}
-
-/*
- * Remap normal tasks to their real PID,
- * CPU shadow threads are mapped to -CPU - 2
- */
-static inline int shadow_pid(int realpid)
-{
-        if (realpid)
-                return realpid;
-
-        return -raw_smp_processor_id() - 2;
-}
-
-static char gdbmsgbuf[BUFMAX + 1];
-
-static void kgdb_msg_write(const char *s, int len)
-{
-        char *bufptr;
-        int wcount;
-        int i;
-
-        /* 'O'utput */
-        gdbmsgbuf[0] = 'O';
-
-        /* Fill and send buffers... */
-        while (len > 0) {
-                bufptr = gdbmsgbuf + 1;
-
-                /* Calculate how many this time */
-                if ((len << 1) > (BUFMAX - 2))
-                        wcount = (BUFMAX - 2) >> 1;
-                else
-                        wcount = len;
-
-                /* Pack in hex chars */
-                for (i = 0; i < wcount; i++)
-                        bufptr = pack_hex_byte(bufptr, s[i]);
-                *bufptr = '\0';
-
-                /* Move up */
-                s += wcount;
-                len -= wcount;
-
-                /* Write packet */
-                put_packet(gdbmsgbuf);
-        }
-}
-
-/*
- * Return true if there is a valid kgdb I/O module.  Also if no
- * debugger is attached a message can be printed to the console about
- * waiting for the debugger to attach.
- *
- * The print_wait argument is only to be true when called from inside
- * the core kgdb_handle_exception, because it will wait for the
- * debugger to attach.
- */
-static int kgdb_io_ready(int print_wait)
-{
-        if (!kgdb_io_ops)
-                return 0;
-        if (kgdb_connected)
-                return 1;
-        if (atomic_read(&kgdb_setting_breakpoint))
-                return 1;
-        if (print_wait)
-                printk(KERN_CRIT "KGDB: Waiting for remote debugger\n");
-        return 1;
-}
-
-/*
- * All the functions that start with gdb_cmd are the various
- * operations to implement the handlers for the gdbserial protocol
- * where KGDB is communicating with an external debugger
- */
-
-/* Handle the '?' status packets */
-static void gdb_cmd_status(struct kgdb_state *ks)
-{
-        /*
-         * We know that this packet is only sent
-         * during initial connect.  So to be safe,
-         * we clear out our breakpoints now in case
-         * GDB is reconnecting.
-         */
-        remove_all_break();
-
-        remcom_out_buffer[0] = 'S';
-        pack_hex_byte(&remcom_out_buffer[1], ks->signo);
-}
-
-/* Handle the 'g' get registers request */
-static void gdb_cmd_getregs(struct kgdb_state *ks)
-{
-        struct task_struct *thread;
-        void *local_debuggerinfo;
-        int i;
-
-        thread = kgdb_usethread;
-        if (!thread) {
-                thread = kgdb_info[ks->cpu].task;
-                local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo;
-        } else {
-                local_debuggerinfo = NULL;
-                for_each_online_cpu(i) {
-                        /*
-                         * Try to find the task on some other
-                         * or possibly this node if we do not
-                         * find the matching task then we try
-                         * to approximate the results.
-                         */
-                        if (thread == kgdb_info[i].task)
-                                local_debuggerinfo = kgdb_info[i].debuggerinfo;
-                }
-        }
-
-        /*
-         * All threads that don't have debuggerinfo should be
-         * in schedule() sleeping, since all other CPUs
-         * are in kgdb_wait, and thus have debuggerinfo.
-         */
-        if (local_debuggerinfo) {
-                pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo);
-        } else {
-                /*
-                 * Pull stuff saved during switch_to; nothing
-                 * else is accessible (or even particularly
-                 * relevant).
-                 *
-                 * This should be enough for a stack trace.
-                 */
-                sleeping_thread_to_gdb_regs(gdb_regs, thread);
-        }
-        kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES);
-}
-
-/* Handle the 'G' set registers request */
-static void gdb_cmd_setregs(struct kgdb_state *ks)
-{
-        kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES);
-
-        if (kgdb_usethread && kgdb_usethread != current) {
-                error_packet(remcom_out_buffer, -EINVAL);
-        } else {
-                gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs);
-                strcpy(remcom_out_buffer, "OK");
-        }
-}
-
-/* Handle the 'm' memory read bytes */
-static void gdb_cmd_memread(struct kgdb_state *ks)
-{
-        char *ptr = &remcom_in_buffer[1];
-        unsigned long length;
-        unsigned long addr;
-        int err;
-
-        if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' &&
-                                        kgdb_hex2long(&ptr, &length) > 0) {
-                err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length);
-                if (err)
-                        error_packet(remcom_out_buffer, err);
-        } else {
-                error_packet(remcom_out_buffer, -EINVAL);
-        }
-}
-
-/* Handle the 'M' memory write bytes */
-static void gdb_cmd_memwrite(struct kgdb_state *ks)
-{
-        int err = write_mem_msg(0);
-
-        if (err)
-                error_packet(remcom_out_buffer, err);
-        else
-                strcpy(remcom_out_buffer, "OK");
-}
-
-/* Handle the 'X' memory binary write bytes */
-static void gdb_cmd_binwrite(struct kgdb_state *ks)
-{
-        int err = write_mem_msg(1);
-
-        if (err)
-                error_packet(remcom_out_buffer, err);
-        else
-                strcpy(remcom_out_buffer, "OK");
-}
-
-/* Handle the 'D' or 'k', detach or kill packets */
-static void gdb_cmd_detachkill(struct kgdb_state *ks)
-{
-        int error;
-
-        /* The detach case */
-        if (remcom_in_buffer[0] == 'D') {
-                error = remove_all_break();
-                if (error < 0) {
-                        error_packet(remcom_out_buffer, error);
-                } else {
-                        strcpy(remcom_out_buffer, "OK");
-                        kgdb_connected = 0;
-                }
-                put_packet(remcom_out_buffer);
-        } else {
-                /*
-                 * Assume the kill case, with no exit code checking,
-                 * trying to force detach the debugger:
-                 */
-                remove_all_break();
-                kgdb_connected = 0;
-        }
-}
-
-/* Handle the 'R' reboot packets */
-static int gdb_cmd_reboot(struct kgdb_state *ks)
-{
-        /* For now, only honor R0 */
-        if (strcmp(remcom_in_buffer, "R0") == 0) {
-                printk(KERN_CRIT "Executing emergency reboot\n");
-                strcpy(remcom_out_buffer, "OK");
-                put_packet(remcom_out_buffer);
-
-                /*
-                 * Execution should not return from
-                 * machine_emergency_restart()
-                 */
-                machine_emergency_restart();
-                kgdb_connected = 0;
-
-                return 1;
-        }
-        return 0;
-}
-
-/* Handle the 'q' query packets */
-static void gdb_cmd_query(struct kgdb_state *ks)
-{
-        struct task_struct *g;
-        struct task_struct *p;
-        unsigned char thref[8];
-        char *ptr;
-        int i;
-        int cpu;
-        int finished = 0;
-
-        switch (remcom_in_buffer[1]) {
-        case 's':
-        case 'f':
-                if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) {
-                        error_packet(remcom_out_buffer, -EINVAL);
-                        break;
-                }
-
-                i = 0;
-                remcom_out_buffer[0] = 'm';
-                ptr = remcom_out_buffer + 1;
-                if (remcom_in_buffer[1] == 'f') {
-                        /* Each cpu is a shadow thread */
-                        for_each_online_cpu(cpu) {
-                                ks->thr_query = 0;
-                                int_to_threadref(thref, -cpu - 2);
-                                pack_threadid(ptr, thref);
-                                ptr += BUF_THREAD_ID_SIZE;
-                                *(ptr++) = ',';
-                                i++;
-                        }
-                }
-
-                do_each_thread(g, p) {
-                        if (i >= ks->thr_query && !finished) {
-                                int_to_threadref(thref, p->pid);
-                                pack_threadid(ptr, thref);
-                                ptr += BUF_THREAD_ID_SIZE;
-                                *(ptr++) = ',';
-                                ks->thr_query++;
-                                if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0)
-                                        finished = 1;
-                        }
-                        i++;
-                } while_each_thread(g, p);
-
-                *(--ptr) = '\0';
-                break;
-
-        case 'C':
-                /* Current thread id */
-                strcpy(remcom_out_buffer, "QC");
-                ks->threadid = shadow_pid(current->pid);
-                int_to_threadref(thref, ks->threadid);
-                pack_threadid(remcom_out_buffer + 2, thref);
-                break;
-        case 'T':
-                if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) {
-                        error_packet(remcom_out_buffer, -EINVAL);
-                        break;
-                }
-                ks->threadid = 0;
-                ptr = remcom_in_buffer + 17;
-                kgdb_hex2long(&ptr, &ks->threadid);
-                if (!getthread(ks->linux_regs, ks->threadid)) {
-                        error_packet(remcom_out_buffer, -EINVAL);
-                        break;
-                }
-                if ((int)ks->threadid > 0) {
-                        kgdb_mem2hex(getthread(ks->linux_regs,
-                                        ks->threadid)->comm,
-                                        remcom_out_buffer, 16);
-                } else {
-                        static char tmpstr[23 + BUF_THREAD_ID_SIZE];
-
-                        sprintf(tmpstr, "shadowCPU%d",
-                                        (int)(-ks->threadid - 2));
-                        kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr));
-                }
-                break;
-        }
-}
-
-/* Handle the 'H' task query packets */
-static void gdb_cmd_task(struct kgdb_state *ks)
-{
-        struct task_struct *thread;
-        char *ptr;
-
-        switch (remcom_in_buffer[1]) {
-        case 'g':
-                ptr = &remcom_in_buffer[2];
-                kgdb_hex2long(&ptr, &ks->threadid);
-                thread = getthread(ks->linux_regs, ks->threadid);
-                if (!thread && ks->threadid > 0) {
-                        error_packet(remcom_out_buffer, -EINVAL);
-                        break;
-                }
-                kgdb_usethread = thread;
-                ks->kgdb_usethreadid = ks->threadid;
-                strcpy(remcom_out_buffer, "OK");
-                break;
-        case 'c':
-                ptr = &remcom_in_buffer[2];
-                kgdb_hex2long(&ptr, &ks->threadid);
-                if (!ks->threadid) {
-                        kgdb_contthread = NULL;
-                } else {
-                        thread = getthread(ks->linux_regs, ks->threadid);
-                        if (!thread && ks->threadid > 0) {
-                                error_packet(remcom_out_buffer, -EINVAL);
-                                break;
-                        }
-                        kgdb_contthread = thread;
-                }
-                strcpy(remcom_out_buffer, "OK");
-                break;
-        }
-}
-
-/* Handle the 'T' thread query packets */
-static void gdb_cmd_thread(struct kgdb_state *ks)
-{
-        char *ptr = &remcom_in_buffer[1];
-        struct task_struct *thread;
-
-        kgdb_hex2long(&ptr, &ks->threadid);
-        thread = getthread(ks->linux_regs, ks->threadid);
-        if (thread)
-                strcpy(remcom_out_buffer, "OK");
-        else
-                error_packet(remcom_out_buffer, -EINVAL);
-}
-
-/* Handle the 'z' or 'Z' breakpoint remove or set packets */
-static void gdb_cmd_break(struct kgdb_state *ks)
-{
-        /*
-         * Since GDB-5.3, it's been drafted that '0' is a software
-         * breakpoint, '1' is a hardware breakpoint, so let's do that.
-         */
-        char *bpt_type = &remcom_in_buffer[1];
-        char *ptr = &remcom_in_buffer[2];
-        unsigned long addr;
-        unsigned long length;
-        int error = 0;
-
-        if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') {
-                /* Unsupported */
-                if (*bpt_type > '4')
-                        return;
-        } else {
-                if (*bpt_type != '0' && *bpt_type != '1')
-                        /* Unsupported. */
-                        return;
-        }
-
-        /*
-         * Test if this is a hardware breakpoint, and
-         * if we support it:
-         */
-        if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT))
-                /* Unsupported. */
-                return;
-
-        if (*(ptr++) != ',') {
-                error_packet(remcom_out_buffer, -EINVAL);
-                return;
-        }
-        if (!kgdb_hex2long(&ptr, &addr)) {
-                error_packet(remcom_out_buffer, -EINVAL);
-                return;
-        }
-        if (*(ptr++) != ',' ||
-                !kgdb_hex2long(&ptr, &length)) {
-                error_packet(remcom_out_buffer, -EINVAL);
-                return;
-        }
-
-        if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0')
-                error = kgdb_set_sw_break(addr);
-        else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0')
-                error = kgdb_remove_sw_break(addr);
-        else if (remcom_in_buffer[0] == 'Z')
-                error = arch_kgdb_ops.set_hw_breakpoint(addr,
-                        (int)length, *bpt_type - '0');
-        else if (remcom_in_buffer[0] == 'z')
-                error = arch_kgdb_ops.remove_hw_breakpoint(addr,
-                        (int) length, *bpt_type - '0');
-
-        if (error == 0)
-                strcpy(remcom_out_buffer, "OK");
-        else
-                error_packet(remcom_out_buffer, error);
-}
-
-/* Handle the 'C' signal / exception passing packets */
-static int gdb_cmd_exception_pass(struct kgdb_state *ks)
-{
-        /* C09 == pass exception
-         * C15 == detach kgdb, pass exception
-         */
-        if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') {
-
-                ks->pass_exception = 1;
-                remcom_in_buffer[0] = 'c';
-
-        } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') {
-
-                ks->pass_exception = 1;
-                remcom_in_buffer[0] = 'D';
-                remove_all_break();
-                kgdb_connected = 0;
-                return 1;
-
-        } else {
-                kgdb_msg_write("KGDB only knows signal 9 (pass)"
-                        " and 15 (pass and disconnect)\n"
-                        "Executing a continue without signal passing\n", 0);
-                remcom_in_buffer[0] = 'c';
-        }
-
-        /* Indicate fall through */
-        return -1;
-}
-
-/*
- * This function performs all gdbserial command procesing
- */
-static int gdb_serial_stub(struct kgdb_state *ks)
-{
-        int error = 0;
-        int tmp;
-
-        /* Clear the out buffer. */
-        memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
-
-        if (kgdb_connected) {
-                unsigned char thref[8];
-                char *ptr;
-
-                /* Reply to host that an exception has occurred */
-                ptr = remcom_out_buffer;
-                *ptr++ = 'T';
-                ptr = pack_hex_byte(ptr, ks->signo);
-                ptr += strlen(strcpy(ptr, "thread:"));
-                int_to_threadref(thref, shadow_pid(current->pid));
-                ptr = pack_threadid(ptr, thref);
-                *ptr++ = ';';
-                put_packet(remcom_out_buffer);
-        }
-
-        kgdb_usethread = kgdb_info[ks->cpu].task;
-        ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid);
-        ks->pass_exception = 0;
-
-        while (1) {
-                error = 0;
-
-                /* Clear the out buffer. */
-                memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
-
-                get_packet(remcom_in_buffer);
-
-                switch (remcom_in_buffer[0]) {
-                case '?': /* gdbserial status */
-                        gdb_cmd_status(ks);
-                        break;
-                case 'g': /* return the value of the CPU registers */
-                        gdb_cmd_getregs(ks);
-                        break;
-                case 'G': /* set the value of the CPU registers - return OK */
-                        gdb_cmd_setregs(ks);
-                        break;
-                case 'm': /* mAA..AA,LLLL  Read LLLL bytes at address AA..AA */
-                        gdb_cmd_memread(ks);
-                        break;
-                case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */
-                        gdb_cmd_memwrite(ks);
-                        break;
-                case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */
-                        gdb_cmd_binwrite(ks);
-                        break;
-                        /* kill or detach. KGDB should treat this like a
-                         * continue.
-                         */
-                case 'D': /* Debugger detach */
-                case 'k': /* Debugger detach via kill */
-                        gdb_cmd_detachkill(ks);
-                        goto default_handle;
-                case 'R': /* Reboot */
-                        if (gdb_cmd_reboot(ks))
-                                goto default_handle;
-                        break;
-                case 'q': /* query command */
-                        gdb_cmd_query(ks);
-                        break;
-                case 'H': /* task related */
-                        gdb_cmd_task(ks);
-                        break;
-                case 'T': /* Query thread status */
-                        gdb_cmd_thread(ks);
-                        break;
-                case 'z': /* Break point remove */
-                case 'Z': /* Break point set */
-                        gdb_cmd_break(ks);
-                        break;
-                case 'C': /* Exception passing */
-                        tmp = gdb_cmd_exception_pass(ks);
-                        if (tmp > 0)
-                                goto default_handle;
-                        if (tmp == 0)
-                                break;
-                        /* Fall through on tmp < 0 */
-                case 'c': /* Continue packet */
-                case 's': /* Single step packet */
-                        if (kgdb_contthread && kgdb_contthread != current) {
-                                /* Can't switch threads in kgdb */
-                                error_packet(remcom_out_buffer, -EINVAL);
-                                break;
-                        }
-                        kgdb_activate_sw_breakpoints();
-                        /* Fall through to default processing */
-                default:
-default_handle:
-                        error = kgdb_arch_handle_exception(ks->ex_vector,
-                                                ks->signo,
-                                                ks->err_code,
-                                                remcom_in_buffer,
-                                                remcom_out_buffer,
-                                                ks->linux_regs);
-                        /*
-                         * Leave cmd processing on error, detach,
-                         * kill, continue, or single step.
-                         */
-                        if (error >= 0 || remcom_in_buffer[0] == 'D' ||
-                            remcom_in_buffer[0] == 'k') {
-                                error = 0;
-                                goto kgdb_exit;
-                        }
-
-                }
-
-                /* reply to the request */
-                put_packet(remcom_out_buffer);
-        }
-
-kgdb_exit:
-        if (ks->pass_exception)
-                error = 1;
-        return error;
-}
-
-static int kgdb_reenter_check(struct kgdb_state *ks)
-{
-        unsigned long addr;
-
-        if (atomic_read(&kgdb_active) != raw_smp_processor_id())
-                return 0;
-
-        /* Panic on recursive debugger calls: */
-        exception_level++;
-        addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
-        kgdb_deactivate_sw_breakpoints();
-
-        /*
-         * If the break point removed ok at the place exception
-         * occurred, try to recover and print a warning to the end
-         * user because the user planted a breakpoint in a place that
-         * KGDB needs in order to function.
-         */
-        if (kgdb_remove_sw_break(addr) == 0) {
-                exception_level = 0;
-                kgdb_skipexception(ks->ex_vector, ks->linux_regs);
-                kgdb_activate_sw_breakpoints();
-                printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n",
-                        addr);
-                WARN_ON_ONCE(1);
-
-                return 1;
-        }
-        remove_all_break();
-        kgdb_skipexception(ks->ex_vector, ks->linux_regs);
-
-        if (exception_level > 1) {
-                dump_stack();
-                panic("Recursive entry to debugger");
-        }
-
-        printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n");
-        dump_stack();
-        panic("Recursive entry to debugger");
-
-        return 1;
-}
-
-static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
-{
-        unsigned long flags;
-        int sstep_tries = 100;
-        int error = 0;
-        int i, cpu;
-        int trace_on = 0;
-acquirelock:
-        /*
-         * Interrupts will be restored by the 'trap return' code, except when
-         * single stepping.
-         */
-        local_irq_save(flags);
-
-        cpu = ks->cpu;
-        kgdb_info[cpu].debuggerinfo = regs;
-        kgdb_info[cpu].task = current;
-        /*
-         * Make sure the above info reaches the primary CPU before
-         * our cpu_in_kgdb[] flag setting does:
-         */
-        atomic_inc(&cpu_in_kgdb[cpu]);
-
-        /*
-         * CPU will loop if it is a slave or request to become a kgdb
-         * master cpu and acquire the kgdb_active lock:
-         */
-        while (1) {
-                if (kgdb_info[cpu].exception_state & DCPU_WANT_MASTER) {
-                        if (atomic_cmpxchg(&kgdb_active, -1, cpu) == cpu)
-                                break;
-                } else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) {
-                        if (!atomic_read(&passive_cpu_wait[cpu]))
-                                goto return_normal;
-                } else {
-return_normal:
-                        /* Return to normal operation by executing any
-                         * hw breakpoint fixup.
-                         */
-                        if (arch_kgdb_ops.correct_hw_break)
-                                arch_kgdb_ops.correct_hw_break();
-                        if (trace_on)
-                                tracing_on();
-                        atomic_dec(&cpu_in_kgdb[cpu]);
-                        touch_softlockup_watchdog_sync();
-                        clocksource_touch_watchdog();
-                        local_irq_restore(flags);
-                        return 0;
-                }
-                cpu_relax();
-        }
-
-        /*
-         * For single stepping, try to only enter on the processor
-         * that was single stepping.  To gaurd against a deadlock, the
-         * kernel will only try for the value of sstep_tries before
-         * giving up and continuing on.
-         */
-        if (atomic_read(&kgdb_cpu_doing_single_step) != -1 &&
-            (kgdb_info[cpu].task &&
-             kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) {
-                atomic_set(&kgdb_active, -1);
-                touch_softlockup_watchdog_sync();
-                clocksource_touch_watchdog();
-                local_irq_restore(flags);
-
-                goto acquirelock;
-        }
-
-        if (!kgdb_io_ready(1)) {
-                error = 1;
-                goto kgdb_restore; /* No I/O connection, so resume the system */
-        }
-
-        /*
-         * Don't enter if we have hit a removed breakpoint.
-         */
-        if (kgdb_skipexception(ks->ex_vector, ks->linux_regs))
-                goto kgdb_restore;
-
-        /* Call the I/O driver's pre_exception routine */
-        if (kgdb_io_ops->pre_exception)
-                kgdb_io_ops->pre_exception();
-
-        kgdb_disable_hw_debug(ks->linux_regs);
-
-        /*
-         * Get the passive CPU lock which will hold all the non-primary
-         * CPU in a spin state while the debugger is active
-         */
-        if (!kgdb_single_step) {
-                for (i = 0; i < NR_CPUS; i++)
-                        atomic_inc(&passive_cpu_wait[i]);
-        }
-
-#ifdef CONFIG_SMP
-        /* Signal the other CPUs to enter kgdb_wait() */
-        if ((!kgdb_single_step) && kgdb_do_roundup)
-                kgdb_roundup_cpus(flags);
-#endif
-
-        /*
-         * Wait for the other CPUs to be notified and be waiting for us:
-         */
-        for_each_online_cpu(i) {
-                while (!atomic_read(&cpu_in_kgdb[i]))
-                        cpu_relax();
-        }
-
-        /*
-         * At this point the primary processor is completely
-         * in the debugger and all secondary CPUs are quiescent
-         */
-        kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code);
-        kgdb_deactivate_sw_breakpoints();
-        kgdb_single_step = 0;
-        kgdb_contthread = current;
-        exception_level = 0;
-        trace_on = tracing_is_on();
-        if (trace_on)
-                tracing_off();
-
-        /* Talk to debugger with gdbserial protocol */
-        error = gdb_serial_stub(ks);
-
-        /* Call the I/O driver's post_exception routine */
-        if (kgdb_io_ops->post_exception)
-                kgdb_io_ops->post_exception();
-
-        atomic_dec(&cpu_in_kgdb[ks->cpu]);
-
-        if (!kgdb_single_step) {
-                for (i = NR_CPUS-1; i >= 0; i--)
-                        atomic_dec(&passive_cpu_wait[i]);
-                /*
-                 * Wait till all the CPUs have quit
-                 * from the debugger.
-                 */
-                for_each_online_cpu(i) {
-                        while (atomic_read(&cpu_in_kgdb[i]))
-                                cpu_relax();
-                }
-        }
-
-kgdb_restore:
-        if (atomic_read(&kgdb_cpu_doing_single_step) != -1) {
-                int sstep_cpu = atomic_read(&kgdb_cpu_doing_single_step);
-                if (kgdb_info[sstep_cpu].task)
-                        kgdb_sstep_pid = kgdb_info[sstep_cpu].task->pid;
-                else
-                        kgdb_sstep_pid = 0;
-        }
-        if (trace_on)
-                tracing_on();
-        /* Free kgdb_active */
-        atomic_set(&kgdb_active, -1);
-        touch_softlockup_watchdog_sync();
-        clocksource_touch_watchdog();
-        local_irq_restore(flags);
-
-        return error;
-}
-
-/*
- * kgdb_handle_exception() - main entry point from a kernel exception
- *
- * Locking hierarchy:
- *      interface locks, if any (begin_session)
- *      kgdb lock (kgdb_active)
- */
-int
-kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
-{
-        struct kgdb_state kgdb_var;
-        struct kgdb_state *ks = &kgdb_var;
-        int ret;
-
-        ks->cpu                 = raw_smp_processor_id();
-        ks->ex_vector           = evector;
-        ks->signo               = signo;
-        ks->ex_vector           = evector;
-        ks->err_code            = ecode;
-        ks->kgdb_usethreadid    = 0;
-        ks->linux_regs          = regs;
-
-        if (kgdb_reenter_check(ks))
-                return 0; /* Ouch, double exception ! */
-        kgdb_info[ks->cpu].exception_state |= DCPU_WANT_MASTER;
-        ret = kgdb_cpu_enter(ks, regs);
-        kgdb_info[ks->cpu].exception_state &= ~DCPU_WANT_MASTER;
-        return ret;
-}
-
-int kgdb_nmicallback(int cpu, void *regs)
-{
-#ifdef CONFIG_SMP
-        struct kgdb_state kgdb_var;
-        struct kgdb_state *ks = &kgdb_var;
-
-        memset(ks, 0, sizeof(struct kgdb_state));
-        ks->cpu                 = cpu;
-        ks->linux_regs          = regs;
-
-        if (!atomic_read(&cpu_in_kgdb[cpu]) &&
-            atomic_read(&kgdb_active) != -1 &&
-            atomic_read(&kgdb_active) != cpu) {
-                kgdb_info[cpu].exception_state |= DCPU_IS_SLAVE;
-                kgdb_cpu_enter(ks, regs);
-                kgdb_info[cpu].exception_state &= ~DCPU_IS_SLAVE;
-                return 0;
-        }
-#endif
-        return 1;
-}
-
-static void kgdb_console_write(struct console *co, const char *s,
-   unsigned count)
-{
-        unsigned long flags;
-
-        /* If we're debugging, or KGDB has not connected, don't try
-         * and print. */
-        if (!kgdb_connected || atomic_read(&kgdb_active) != -1)
-                return;
-
-        local_irq_save(flags);
-        kgdb_msg_write(s, count);
-        local_irq_restore(flags);
-}
-
-static struct console kgdbcons = {
-        .name           = "kgdb",
-        .write          = kgdb_console_write,
-        .flags          = CON_PRINTBUFFER | CON_ENABLED,
-        .index          = -1,
-};
-
-#ifdef CONFIG_MAGIC_SYSRQ
-static void sysrq_handle_gdb(int key, struct tty_struct *tty)
-{
-        if (!kgdb_io_ops) {
-                printk(KERN_CRIT "ERROR: No KGDB I/O module available\n");
-                return;
-        }
-        if (!kgdb_connected)
-                printk(KERN_CRIT "Entering KGDB\n");
-
-        kgdb_breakpoint();
-}
-
-static struct sysrq_key_op sysrq_gdb_op = {
-        .handler        = sysrq_handle_gdb,
-        .help_msg       = "debug(G)",
-        .action_msg     = "DEBUG",
-};
-#endif
-
-static void kgdb_register_callbacks(void)
-{
-        if (!kgdb_io_module_registered) {
-                kgdb_io_module_registered = 1;
-                kgdb_arch_init();
-#ifdef CONFIG_MAGIC_SYSRQ
-                register_sysrq_key('g', &sysrq_gdb_op);
-#endif
-                if (kgdb_use_con && !kgdb_con_registered) {
-                        register_console(&kgdbcons);
-                        kgdb_con_registered = 1;
-                }
-        }
-}
-
-static void kgdb_unregister_callbacks(void)
-{
-        /*
-         * When this routine is called KGDB should unregister from the
-         * panic handler and clean up, making sure it is not handling any
-         * break exceptions at the time.
-         */
-        if (kgdb_io_module_registered) {
-                kgdb_io_module_registered = 0;
-                kgdb_arch_exit();
-#ifdef CONFIG_MAGIC_SYSRQ
-                unregister_sysrq_key('g', &sysrq_gdb_op);
-#endif
-                if (kgdb_con_registered) {
-                        unregister_console(&kgdbcons);
-                        kgdb_con_registered = 0;
-                }
-        }
-}
-
-static void kgdb_initial_breakpoint(void)
-{
-        kgdb_break_asap = 0;
-
-        printk(KERN_CRIT "kgdb: Waiting for connection from remote gdb...\n");
-        kgdb_breakpoint();
-}
-
-/**
- *      kgdb_register_io_module - register KGDB IO module
- *      @new_kgdb_io_ops: the io ops vector
- *
- *      Register it with the KGDB core.
- */
-int kgdb_register_io_module(struct kgdb_io *new_kgdb_io_ops)
-{
-        int err;
-
-        spin_lock(&kgdb_registration_lock);
-
-        if (kgdb_io_ops) {
-                spin_unlock(&kgdb_registration_lock);
-
-                printk(KERN_ERR "kgdb: Another I/O driver is already "
-                                "registered with KGDB.\n");
-                return -EBUSY;
-        }
-
-        if (new_kgdb_io_ops->init) {
-                err = new_kgdb_io_ops->init();
-                if (err) {
-                        spin_unlock(&kgdb_registration_lock);
-                        return err;
-                }
-        }
-
-        kgdb_io_ops = new_kgdb_io_ops;
-
-        spin_unlock(&kgdb_registration_lock);
-
-        printk(KERN_INFO "kgdb: Registered I/O driver %s.\n",
-               new_kgdb_io_ops->name);
-
-        /* Arm KGDB now. */
-        kgdb_register_callbacks();
-
-        if (kgdb_break_asap)
-                kgdb_initial_breakpoint();
-
-        return 0;
-}
-EXPORT_SYMBOL_GPL(kgdb_register_io_module);
-
-/**
- *      kkgdb_unregister_io_module - unregister KGDB IO module
- *      @old_kgdb_io_ops: the io ops vector
- *
- *      Unregister it with the KGDB core.
- */
-void kgdb_unregister_io_module(struct kgdb_io *old_kgdb_io_ops)
-{
-        BUG_ON(kgdb_connected);
-
-        /*
-         * KGDB is no longer able to communicate out, so
-         * unregister our callbacks and reset state.
-         */
-        kgdb_unregister_callbacks();
-
-        spin_lock(&kgdb_registration_lock);
-
-        WARN_ON_ONCE(kgdb_io_ops != old_kgdb_io_ops);
-        kgdb_io_ops = NULL;
-
-        spin_unlock(&kgdb_registration_lock);
-
-        printk(KERN_INFO
-                "kgdb: Unregistered I/O driver %s, debugger disabled.\n",
-                old_kgdb_io_ops->name);
-}
-EXPORT_SYMBOL_GPL(kgdb_unregister_io_module);
-
-/**
- * kgdb_breakpoint - generate breakpoint exception
- *
- * This function will generate a breakpoint exception.  It is used at the
- * beginning of a program to sync up with a debugger and can be used
- * otherwise as a quick means to stop program execution and "break" into
- * the debugger.
- */
-void kgdb_breakpoint(void)
-{
-        atomic_inc(&kgdb_setting_breakpoint);
-        wmb(); /* Sync point before breakpoint */
-        arch_kgdb_breakpoint();
-        wmb(); /* Sync point after breakpoint */
-        atomic_dec(&kgdb_setting_breakpoint);
-}
-EXPORT_SYMBOL_GPL(kgdb_breakpoint);
-
-static int __init opt_kgdb_wait(char *str)
-{
-        kgdb_break_asap = 1;
-
-        if (kgdb_io_module_registered)
-                kgdb_initial_breakpoint();
-
-        return 0;
-}
-
-early_param("kgdbwait", opt_kgdb_wait);
diff --git a/kernel/kmod.c b/kernel/kmod.c
index bf0e231d9702..6e9b19667a8d 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -116,27 +116,16 @@ int __request_module(bool wait, const char *fmt, ...)
 
         trace_module_request(module_name, wait, _RET_IP_);
 
-        ret = call_usermodehelper(modprobe_path, argv, envp,
-                        wait ? UMH_WAIT_PROC : UMH_WAIT_EXEC);
+        ret = call_usermodehelper_fns(modprobe_path, argv, envp,
+                        wait ? UMH_WAIT_PROC : UMH_WAIT_EXEC,
+                        NULL, NULL, NULL);
+
         atomic_dec(&kmod_concurrent);
         return ret;
 }
 EXPORT_SYMBOL(__request_module);
 #endif /* CONFIG_MODULES */
 
-struct subprocess_info {
-        struct work_struct work;
-        struct completion *complete;
-        struct cred *cred;
-        char *path;
-        char **argv;
-        char **envp;
-        enum umh_wait wait;
-        int retval;
-        struct file *stdin;
-        void (*cleanup)(char **argv, char **envp);
-};
-
 /*
  * This is the task which runs the usermode application
  */
@@ -145,36 +134,10 @@ static int ____call_usermodehelper(void *data)
         struct subprocess_info *sub_info = data;
         int retval;
 
-        BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
-
-        /* Unblock all signals */
         spin_lock_irq(&current->sighand->siglock);
         flush_signal_handlers(current, 1);
-        sigemptyset(&current->blocked);
-        recalc_sigpending();
         spin_unlock_irq(&current->sighand->siglock);
 
-        /* Install the credentials */
-        commit_creds(sub_info->cred);
-        sub_info->cred = NULL;
-
-        /* Install input pipe when needed */
-        if (sub_info->stdin) {
-                struct files_struct *f = current->files;
-                struct fdtable *fdt;
-                /* no races because files should be private here */
-                sys_close(0);
-                fd_install(0, sub_info->stdin);
-                spin_lock(&f->file_lock);
-                fdt = files_fdtable(f);
-                FD_SET(0, fdt->open_fds);
-                FD_CLR(0, fdt->close_on_exec);
-                spin_unlock(&f->file_lock);
-
-                /* and disallow core files too */
-                current->signal->rlim[RLIMIT_CORE] = (struct rlimit){0, 0};
-        }
-
         /* We can run anywhere, unlike our parent keventd(). */
         set_cpus_allowed_ptr(current, cpu_all_mask);
 
@@ -184,9 +147,16 @@ static int ____call_usermodehelper(void *data)
          */
         set_user_nice(current, 0);
 
+        if (sub_info->init) {
+                retval = sub_info->init(sub_info);
+                if (retval)
+                        goto fail;
+        }
+
         retval = kernel_execve(sub_info->path, sub_info->argv, sub_info->envp);
 
         /* Exec failed? */
+fail:
         sub_info->retval = retval;
         do_exit(0);
 }
@@ -194,9 +164,7 @@ static int ____call_usermodehelper(void *data)
 void call_usermodehelper_freeinfo(struct subprocess_info *info)
 {
         if (info->cleanup)
-                (*info->cleanup)(info->argv, info->envp);
-        if (info->cred)
-                put_cred(info->cred);
+                (*info->cleanup)(info);
         kfree(info);
 }
 EXPORT_SYMBOL(call_usermodehelper_freeinfo);
@@ -207,16 +175,16 @@ static int wait_for_helper(void *data)
         struct subprocess_info *sub_info = data;
         pid_t pid;
 
-        /* Install a handler: if SIGCLD isn't handled sys_wait4 won't
-         * populate the status, but will return -ECHILD. */
-        allow_signal(SIGCHLD);
+        /* If SIGCLD is ignored sys_wait4 won't populate the status. */
+        spin_lock_irq(&current->sighand->siglock);
+        current->sighand->action[SIGCHLD-1].sa.sa_handler = SIG_DFL;
+        spin_unlock_irq(&current->sighand->siglock);
 
         pid = kernel_thread(____call_usermodehelper, sub_info, SIGCHLD);
         if (pid < 0) {
                 sub_info->retval = pid;
         } else {
-                int ret;
-
+                int ret = -ECHILD;
                 /*
                  * Normally it is bogus to call wait4() from in-kernel because
                  * wait4() wants to write the exit code to a userspace address.
@@ -237,10 +205,7 @@ static int wait_for_helper(void *data)
                         sub_info->retval = ret;
         }
 
-        if (sub_info->wait == UMH_NO_WAIT)
-                call_usermodehelper_freeinfo(sub_info);
-        else
-                complete(sub_info->complete);
+        complete(sub_info->complete);
         return 0;
 }
 
@@ -249,15 +214,13 @@ static void __call_usermodehelper(struct work_struct *work)
 {
         struct subprocess_info *sub_info =
                 container_of(work, struct subprocess_info, work);
-        pid_t pid;
         enum umh_wait wait = sub_info->wait;
-
-        BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
+        pid_t pid;
 
         /* CLONE_VFORK: wait until the usermode helper has execve'd
          * successfully We need the data structures to stay around
          * until that is done.  */
-        if (wait == UMH_WAIT_PROC || wait == UMH_NO_WAIT)
+        if (wait == UMH_WAIT_PROC)
                 pid = kernel_thread(wait_for_helper, sub_info,
                                     CLONE_FS | CLONE_FILES | SIGCHLD);
         else
@@ -266,15 +229,16 @@ static void __call_usermodehelper(struct work_struct *work)
 
         switch (wait) {
         case UMH_NO_WAIT:
+                call_usermodehelper_freeinfo(sub_info);
                 break;
 
         case UMH_WAIT_PROC:
                 if (pid > 0)
                         break;
-                sub_info->retval = pid;
                 /* FALLTHROUGH */
-
         case UMH_WAIT_EXEC:
+                if (pid < 0)
+                        sub_info->retval = pid;
                 complete(sub_info->complete);
         }
 }
@@ -376,80 +340,37 @@ struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
         sub_info->path = path;
         sub_info->argv = argv;
         sub_info->envp = envp;
-        sub_info->cred = prepare_usermodehelper_creds();
-        if (!sub_info->cred) {
-                kfree(sub_info);
-                return NULL;
-        }
-
   out:
         return sub_info;
 }
 EXPORT_SYMBOL(call_usermodehelper_setup);
 
 /**
- * call_usermodehelper_setkeys - set the session keys for usermode helper
- * @info: a subprocess_info returned by call_usermodehelper_setup
- * @session_keyring: the session keyring for the process
- */
-void call_usermodehelper_setkeys(struct subprocess_info *info,
-                                 struct key *session_keyring)
-{
-#ifdef CONFIG_KEYS
-        struct thread_group_cred *tgcred = info->cred->tgcred;
-        key_put(tgcred->session_keyring);
-        tgcred->session_keyring = key_get(session_keyring);
-#else
-        BUG();
-#endif
-}
-EXPORT_SYMBOL(call_usermodehelper_setkeys);
-
-/**
- * call_usermodehelper_setcleanup - set a cleanup function
+ * call_usermodehelper_setfns - set a cleanup/init function
  * @info: a subprocess_info returned by call_usermodehelper_setup
  * @cleanup: a cleanup function
+ * @init: an init function
+ * @data: arbitrary context sensitive data
  *
- * The cleanup function is just befor ethe subprocess_info is about to
+ * The init function is used to customize the helper process prior to
+ * exec.  A non-zero return code causes the process to error out, exit,
+ * and return the failure to the calling process
+ *
+ * The cleanup function is just before ethe subprocess_info is about to
  * be freed.  This can be used for freeing the argv and envp.  The
  * Function must be runnable in either a process context or the
  * context in which call_usermodehelper_exec is called.
  */
-void call_usermodehelper_setcleanup(struct subprocess_info *info,
-                                    void (*cleanup)(char **argv, char **envp))
+void call_usermodehelper_setfns(struct subprocess_info *info,
+                    int (*init)(struct subprocess_info *info),
+                    void (*cleanup)(struct subprocess_info *info),
+                    void *data)
 {
         info->cleanup = cleanup;
+        info->init = init;
+        info->data = data;
 }
-EXPORT_SYMBOL(call_usermodehelper_setcleanup);
-
-/**
- * call_usermodehelper_stdinpipe - set up a pipe to be used for stdin
- * @sub_info: a subprocess_info returned by call_usermodehelper_setup
- * @filp: set to the write-end of a pipe
- *
- * This constructs a pipe, and sets the read end to be the stdin of the
- * subprocess, and returns the write-end in *@filp.
- */
-int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info,
-                                  struct file **filp)
-{
-        struct file *f;
-
-        f = create_write_pipe(0);
-        if (IS_ERR(f))
-                return PTR_ERR(f);
-        *filp = f;
-
-        f = create_read_pipe(f, 0);
-        if (IS_ERR(f)) {
-                free_write_pipe(*filp);
-                return PTR_ERR(f);
-        }
-        sub_info->stdin = f;
-
-        return 0;
-}
-EXPORT_SYMBOL(call_usermodehelper_stdinpipe);
+EXPORT_SYMBOL(call_usermodehelper_setfns);
 
 /**
  * call_usermodehelper_exec - start a usermode application
@@ -469,9 +390,6 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info,
         DECLARE_COMPLETION_ONSTACK(done);
         int retval = 0;
 
-        BUG_ON(atomic_read(&sub_info->cred->usage) != 1);
-        validate_creds(sub_info->cred);
-
         helper_lock();
         if (sub_info->path[0] == '\0')
                 goto out;
@@ -498,41 +416,6 @@ unlock:
 }
 EXPORT_SYMBOL(call_usermodehelper_exec);
 
-/**
- * call_usermodehelper_pipe - call a usermode helper process with a pipe stdin
- * @path: path to usermode executable
- * @argv: arg vector for process
- * @envp: environment for process
- * @filp: set to the write-end of a pipe
- *
- * This is a simple wrapper which executes a usermode-helper function
- * with a pipe as stdin.  It is implemented entirely in terms of
- * lower-level call_usermodehelper_* functions.
- */
-int call_usermodehelper_pipe(char *path, char **argv, char **envp,
-                             struct file **filp)
-{
-        struct subprocess_info *sub_info;
-        int ret;
-
-        sub_info = call_usermodehelper_setup(path, argv, envp, GFP_KERNEL);
-        if (sub_info == NULL)
-                return -ENOMEM;
-
-        ret = call_usermodehelper_stdinpipe(sub_info, filp);
-        if (ret < 0) {
-                call_usermodehelper_freeinfo(sub_info);
-                return ret;
-        }
-
-        ret = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC);
-        if (ret < 0)    /* Failed to execute helper, close pipe */
-                filp_close(*filp, NULL);
-
-        return ret;
-}
-EXPORT_SYMBOL(call_usermodehelper_pipe);
-
 void __init usermodehelper_init(void)
 {
         khelper_wq = create_singlethread_workqueue("khelper");
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 0ed46f3e51e9..282035f3ae96 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1588,6 +1588,72 @@ static void __kprobes kill_kprobe(struct kprobe *p)
         arch_remove_kprobe(p);
 }
 
+/* Disable one kprobe */
+int __kprobes disable_kprobe(struct kprobe *kp)
+{
+        int ret = 0;
+        struct kprobe *p;
+
+        mutex_lock(&kprobe_mutex);
+
+        /* Check whether specified probe is valid. */
+        p = __get_valid_kprobe(kp);
+        if (unlikely(p == NULL)) {
+                ret = -EINVAL;
+                goto out;
+        }
+
+        /* If the probe is already disabled (or gone), just return */
+        if (kprobe_disabled(kp))
+                goto out;
+
+        kp->flags |= KPROBE_FLAG_DISABLED;
+        if (p != kp)
+                /* When kp != p, p is always enabled. */
+                try_to_disable_aggr_kprobe(p);
+
+        if (!kprobes_all_disarmed && kprobe_disabled(p))
+                disarm_kprobe(p);
+out:
+        mutex_unlock(&kprobe_mutex);
+        return ret;
+}
+EXPORT_SYMBOL_GPL(disable_kprobe);
+
+/* Enable one kprobe */
+int __kprobes enable_kprobe(struct kprobe *kp)
+{
+        int ret = 0;
+        struct kprobe *p;
+
+        mutex_lock(&kprobe_mutex);
+
+        /* Check whether specified probe is valid. */
+        p = __get_valid_kprobe(kp);
+        if (unlikely(p == NULL)) {
+                ret = -EINVAL;
+                goto out;
+        }
+
+        if (kprobe_gone(kp)) {
+                /* This kprobe has gone, we couldn't enable it. */
+                ret = -EINVAL;
+                goto out;
+        }
+
+        if (p != kp)
+                kp->flags &= ~KPROBE_FLAG_DISABLED;
+
+        if (!kprobes_all_disarmed && kprobe_disabled(p)) {
+                p->flags &= ~KPROBE_FLAG_DISABLED;
+                arm_kprobe(p);
+        }
+out:
+        mutex_unlock(&kprobe_mutex);
+        return ret;
+}
+EXPORT_SYMBOL_GPL(enable_kprobe);
+
 void __kprobes dump_kprobe(struct kprobe *kp)
 {
         printk(KERN_WARNING "Dumping kprobe:\n");
@@ -1805,72 +1871,6 @@ static const struct file_operations debugfs_kprobes_operations = {
         .release        = seq_release,
 };
 
-/* Disable one kprobe */
-int __kprobes disable_kprobe(struct kprobe *kp)
-{
-        int ret = 0;
-        struct kprobe *p;
-
-        mutex_lock(&kprobe_mutex);
-
-        /* Check whether specified probe is valid. */
-        p = __get_valid_kprobe(kp);
-        if (unlikely(p == NULL)) {
-                ret = -EINVAL;
-                goto out;
-        }
-
-        /* If the probe is already disabled (or gone), just return */
-        if (kprobe_disabled(kp))
-                goto out;
-
-        kp->flags |= KPROBE_FLAG_DISABLED;
-        if (p != kp)
-                /* When kp != p, p is always enabled. */
-                try_to_disable_aggr_kprobe(p);
-
-        if (!kprobes_all_disarmed && kprobe_disabled(p))
-                disarm_kprobe(p);
-out:
-        mutex_unlock(&kprobe_mutex);
-        return ret;
-}
-EXPORT_SYMBOL_GPL(disable_kprobe);
-
-/* Enable one kprobe */
-int __kprobes enable_kprobe(struct kprobe *kp)
-{
-        int ret = 0;
-        struct kprobe *p;
-
-        mutex_lock(&kprobe_mutex);
-
-        /* Check whether specified probe is valid. */
-        p = __get_valid_kprobe(kp);
-        if (unlikely(p == NULL)) {
-                ret = -EINVAL;
-                goto out;
-        }
-
-        if (kprobe_gone(kp)) {
-                /* This kprobe has gone, we couldn't enable it. */
-                ret = -EINVAL;
-                goto out;
-        }
-
-        if (p != kp)
-                kp->flags &= ~KPROBE_FLAG_DISABLED;
-
-        if (!kprobes_all_disarmed && kprobe_disabled(p)) {
-                p->flags &= ~KPROBE_FLAG_DISABLED;
-                arm_kprobe(p);
-        }
-out:
-        mutex_unlock(&kprobe_mutex);
-        return ret;
-}
-EXPORT_SYMBOL_GPL(enable_kprobe);
-
 static void __kprobes arm_all_kprobes(void)
 {
         struct hlist_head *head;
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 21fe3c426948..0b624e791805 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -138,7 +138,8 @@ extern const void __start_notes __attribute__((weak));
 extern const void __stop_notes __attribute__((weak));
 #define notes_size (&__stop_notes - &__start_notes)
 
-static ssize_t notes_read(struct kobject *kobj, struct bin_attribute *bin_attr,
+static ssize_t notes_read(struct file *filp, struct kobject *kobj,
+                          struct bin_attribute *bin_attr,
                           char *buf, loff_t off, size_t count)
 {
         memcpy(buf, &__start_notes + off, count);
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 2594e1ce41cb..54286798c37b 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -431,20 +431,7 @@ static struct stack_trace lockdep_init_trace = {
 /*
  * Various lockdep statistics:
  */
-atomic_t chain_lookup_hits;
-atomic_t chain_lookup_misses;
-atomic_t hardirqs_on_events;
-atomic_t hardirqs_off_events;
-atomic_t redundant_hardirqs_on;
-atomic_t redundant_hardirqs_off;
-atomic_t softirqs_on_events;
-atomic_t softirqs_off_events;
-atomic_t redundant_softirqs_on;
-atomic_t redundant_softirqs_off;
-atomic_t nr_unused_locks;
-atomic_t nr_cyclic_checks;
-atomic_t nr_find_usage_forwards_checks;
-atomic_t nr_find_usage_backwards_checks;
+DEFINE_PER_CPU(struct lockdep_stats, lockdep_stats);
 #endif
 
 /*
@@ -748,7 +735,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
                 return NULL;
         }
         class = lock_classes + nr_lock_classes++;
-        debug_atomic_inc(&nr_unused_locks);
+        debug_atomic_inc(nr_unused_locks);
         class->key = key;
         class->name = lock->name;
         class->subclass = subclass;
@@ -818,7 +805,8 @@ static struct lock_list *alloc_list_entry(void)
  * Add a new dependency to the head of the list:
  */
 static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
-                            struct list_head *head, unsigned long ip, int distance)
+                            struct list_head *head, unsigned long ip,
+                            int distance, struct stack_trace *trace)
 {
         struct lock_list *entry;
         /*
@@ -829,11 +817,9 @@ static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
         if (!entry)
                 return 0;
 
-        if (!save_trace(&entry->trace))
-                return 0;
-
         entry->class = this;
         entry->distance = distance;
+        entry->trace = *trace;
         /*
          * Since we never remove from the dependency list, the list can
          * be walked lockless by other CPUs, it's only allocation
@@ -1205,7 +1191,7 @@ check_noncircular(struct lock_list *root, struct lock_class *target,
 {
         int result;
 
-        debug_atomic_inc(&nr_cyclic_checks);
+        debug_atomic_inc(nr_cyclic_checks);
 
         result = __bfs_forwards(root, target, class_equal, target_entry);
 
@@ -1242,7 +1228,7 @@ find_usage_forwards(struct lock_list *root, enum lock_usage_bit bit,
 {
         int result;
 
-        debug_atomic_inc(&nr_find_usage_forwards_checks);
+        debug_atomic_inc(nr_find_usage_forwards_checks);
 
         result = __bfs_forwards(root, (void *)bit, usage_match, target_entry);
 
@@ -1265,7 +1251,7 @@ find_usage_backwards(struct lock_list *root, enum lock_usage_bit bit,
 {
         int result;
 
-        debug_atomic_inc(&nr_find_usage_backwards_checks);
+        debug_atomic_inc(nr_find_usage_backwards_checks);
 
         result = __bfs_backwards(root, (void *)bit, usage_match, target_entry);
 
@@ -1635,12 +1621,20 @@ check_deadlock(struct task_struct *curr, struct held_lock *next,
  */
 static int
 check_prev_add(struct task_struct *curr, struct held_lock *prev,
-               struct held_lock *next, int distance)
+               struct held_lock *next, int distance, int trylock_loop)
 {
         struct lock_list *entry;
         int ret;
         struct lock_list this;
         struct lock_list *uninitialized_var(target_entry);
+        /*
+         * Static variable, serialized by the graph_lock().
+         *
+         * We use this static variable to save the stack trace in case
+         * we call into this function multiple times due to encountering
+         * trylocks in the held lock stack.
+         */
+        static struct stack_trace trace;
 
         /*
          * Prove that the new <prev> -> <next> dependency would not
@@ -1688,20 +1682,23 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
                 }
         }
 
+        if (!trylock_loop && !save_trace(&trace))
+                return 0;
+
         /*
          * Ok, all validations passed, add the new lock
          * to the previous lock's dependency list:
          */
         ret = add_lock_to_list(hlock_class(prev), hlock_class(next),
                                &hlock_class(prev)->locks_after,
-                               next->acquire_ip, distance);
+                               next->acquire_ip, distance, &trace);
 
         if (!ret)
                 return 0;
 
         ret = add_lock_to_list(hlock_class(next), hlock_class(prev),
                                &hlock_class(next)->locks_before,
-                               next->acquire_ip, distance);
+                               next->acquire_ip, distance, &trace);
         if (!ret)
                 return 0;
 
@@ -1731,6 +1728,7 @@ static int
 check_prevs_add(struct task_struct *curr, struct held_lock *next)
 {
         int depth = curr->lockdep_depth;
+        int trylock_loop = 0;
         struct held_lock *hlock;
 
         /*
@@ -1756,7 +1754,8 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
                  * added:
                  */
                 if (hlock->read != 2) {
-                        if (!check_prev_add(curr, hlock, next, distance))
+                        if (!check_prev_add(curr, hlock, next,
+                                                distance, trylock_loop))
                                 return 0;
                         /*
                          * Stop after the first non-trylock entry,
@@ -1779,6 +1778,7 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
                 if (curr->held_locks[depth].irq_context !=
                                 curr->held_locks[depth-1].irq_context)
                         break;
+                trylock_loop = 1;
         }
         return 1;
 out_bug:
@@ -1825,7 +1825,7 @@ static inline int lookup_chain_cache(struct task_struct *curr,
         list_for_each_entry(chain, hash_head, entry) {
                 if (chain->chain_key == chain_key) {
 cache_hit:
-                        debug_atomic_inc(&chain_lookup_hits);
+                        debug_atomic_inc(chain_lookup_hits);
                         if (very_verbose(class))
                                 printk("\nhash chain already cached, key: "
                                         "%016Lx tail class: [%p] %s\n",
@@ -1890,7 +1890,7 @@ cache_hit:
                 chain_hlocks[chain->base + j] = class - lock_classes;
         }
         list_add_tail_rcu(&chain->entry, hash_head);
-        debug_atomic_inc(&chain_lookup_misses);
+        debug_atomic_inc(chain_lookup_misses);
         inc_chains();
 
         return 1;
@@ -2311,7 +2311,12 @@ void trace_hardirqs_on_caller(unsigned long ip)
                 return;
 
         if (unlikely(curr->hardirqs_enabled)) {
-                debug_atomic_inc(&redundant_hardirqs_on);
+                /*
+                 * Neither irq nor preemption are disabled here
+                 * so this is racy by nature but loosing one hit
+                 * in a stat is not a big deal.
+                 */
+                __debug_atomic_inc(redundant_hardirqs_on);
                 return;
         }
         /* we'll do an OFF -> ON transition: */
@@ -2338,7 +2343,7 @@ void trace_hardirqs_on_caller(unsigned long ip)
 
         curr->hardirq_enable_ip = ip;
         curr->hardirq_enable_event = ++curr->irq_events;
-        debug_atomic_inc(&hardirqs_on_events);
+        debug_atomic_inc(hardirqs_on_events);
 }
 EXPORT_SYMBOL(trace_hardirqs_on_caller);
 
@@ -2370,9 +2375,9 @@ void trace_hardirqs_off_caller(unsigned long ip)
                 curr->hardirqs_enabled = 0;
                 curr->hardirq_disable_ip = ip;
                 curr->hardirq_disable_event = ++curr->irq_events;
-                debug_atomic_inc(&hardirqs_off_events);
+                debug_atomic_inc(hardirqs_off_events);
         } else
-                debug_atomic_inc(&redundant_hardirqs_off);
+                debug_atomic_inc(redundant_hardirqs_off);
 }
 EXPORT_SYMBOL(trace_hardirqs_off_caller);
 
@@ -2396,7 +2401,7 @@ void trace_softirqs_on(unsigned long ip)
                 return;
 
         if (curr->softirqs_enabled) {
-                debug_atomic_inc(&redundant_softirqs_on);
+                debug_atomic_inc(redundant_softirqs_on);
                 return;
         }
 
@@ -2406,7 +2411,7 @@ void trace_softirqs_on(unsigned long ip)
         curr->softirqs_enabled = 1;
         curr->softirq_enable_ip = ip;
         curr->softirq_enable_event = ++curr->irq_events;
-        debug_atomic_inc(&softirqs_on_events);
+        debug_atomic_inc(softirqs_on_events);
         /*
          * We are going to turn softirqs on, so set the
          * usage bit for all held locks, if hardirqs are
@@ -2436,10 +2441,10 @@ void trace_softirqs_off(unsigned long ip)
                 curr->softirqs_enabled = 0;
                 curr->softirq_disable_ip = ip;
                 curr->softirq_disable_event = ++curr->irq_events;
-                debug_atomic_inc(&softirqs_off_events);
+                debug_atomic_inc(softirqs_off_events);
                 DEBUG_LOCKS_WARN_ON(!softirq_count());
         } else
-                debug_atomic_inc(&redundant_softirqs_off);
+                debug_atomic_inc(redundant_softirqs_off);
 }
 
 static void __lockdep_trace_alloc(gfp_t gfp_mask, unsigned long flags)
@@ -2644,7 +2649,7 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
                         return 0;
                 break;
         case LOCK_USED:
-                debug_atomic_dec(&nr_unused_locks);
+                debug_atomic_dec(nr_unused_locks);
                 break;
         default:
                 if (!debug_locks_off_graph_unlock())
@@ -2706,6 +2711,8 @@ void lockdep_init_map(struct lockdep_map *lock, const char *name,
 }
 EXPORT_SYMBOL_GPL(lockdep_init_map);
 
+struct lock_class_key __lockdep_no_validate__;
+
 /*
  * This gets called for every mutex_lock*()/spin_lock*() operation.
  * We maintain the dependency maps and validate the locking attempt:
@@ -2740,6 +2747,9 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
                 return 0;
         }
 
+        if (lock->key == &__lockdep_no_validate__)
+                check = 1;
+
         if (!subclass)
                 class = lock->class_cache;
         /*
@@ -2750,7 +2760,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
                 if (!class)
                         return 0;
         }
-        debug_atomic_inc((atomic_t *)&class->ops);
+        atomic_inc((atomic_t *)&class->ops);
         if (very_verbose(class)) {
                 printk("\nacquire class [%p] %s", class->key, class->name);
                 if (class->name_version > 1)
@@ -3227,7 +3237,7 @@ void lock_release(struct lockdep_map *lock, int nested,
         raw_local_irq_save(flags);
         check_flags(flags);
         current->lockdep_recursion = 1;
-        trace_lock_release(lock, nested, ip);
+        trace_lock_release(lock, ip);
         __lock_release(lock, nested, ip);
         current->lockdep_recursion = 0;
         raw_local_irq_restore(flags);
@@ -3380,7 +3390,7 @@ found_it:
                 hlock->holdtime_stamp = now;
         }
 
-        trace_lock_acquired(lock, ip, waittime);
+        trace_lock_acquired(lock, ip);
 
         stats = get_lock_stats(hlock_class(hlock));
         if (waittime) {
@@ -3801,8 +3811,11 @@ void lockdep_rcu_dereference(const char *file, const int line)
 {
         struct task_struct *curr = current;
 
+#ifndef CONFIG_PROVE_RCU_REPEATEDLY
         if (!debug_locks_off())
                 return;
+#endif /* #ifdef CONFIG_PROVE_RCU_REPEATEDLY */
+        /* Note: the following can be executed concurrently, so be careful. */
         printk("\n===================================================\n");
         printk(  "[ INFO: suspicious rcu_dereference_check() usage. ]\n");
         printk(  "---------------------------------------------------\n");
diff --git a/kernel/lockdep_internals.h b/kernel/lockdep_internals.h
index a2ee95ad1313..4f560cfedc8f 100644
--- a/kernel/lockdep_internals.h
+++ b/kernel/lockdep_internals.h
@@ -110,30 +110,60 @@ lockdep_count_backward_deps(struct lock_class *class)
 #endif
 
 #ifdef CONFIG_DEBUG_LOCKDEP
+
+#include <asm/local.h>
 /*
- * Various lockdep statistics:
+ * Various lockdep statistics.
+ * We want them per cpu as they are often accessed in fast path
+ * and we want to avoid too much cache bouncing.
  */
-extern atomic_t chain_lookup_hits;
-extern atomic_t chain_lookup_misses;
-extern atomic_t hardirqs_on_events;
-extern atomic_t hardirqs_off_events;
-extern atomic_t redundant_hardirqs_on;
-extern atomic_t redundant_hardirqs_off;
-extern atomic_t softirqs_on_events;
-extern atomic_t softirqs_off_events;
-extern atomic_t redundant_softirqs_on;
-extern atomic_t redundant_softirqs_off;
-extern atomic_t nr_unused_locks;
-extern atomic_t nr_cyclic_checks;
-extern atomic_t nr_cyclic_check_recursions;
-extern atomic_t nr_find_usage_forwards_checks;
-extern atomic_t nr_find_usage_forwards_recursions;
-extern atomic_t nr_find_usage_backwards_checks;
-extern atomic_t nr_find_usage_backwards_recursions;
-# define debug_atomic_inc(ptr)          atomic_inc(ptr)
-# define debug_atomic_dec(ptr)          atomic_dec(ptr)
-# define debug_atomic_read(ptr)         atomic_read(ptr)
+struct lockdep_stats {
+        int     chain_lookup_hits;
+        int     chain_lookup_misses;
+        int     hardirqs_on_events;
+        int     hardirqs_off_events;
+        int     redundant_hardirqs_on;
+        int     redundant_hardirqs_off;
+        int     softirqs_on_events;
+        int     softirqs_off_events;
+        int     redundant_softirqs_on;
+        int     redundant_softirqs_off;
+        int     nr_unused_locks;
+        int     nr_cyclic_checks;
+        int     nr_cyclic_check_recursions;
+        int     nr_find_usage_forwards_checks;
+        int     nr_find_usage_forwards_recursions;
+        int     nr_find_usage_backwards_checks;
+        int     nr_find_usage_backwards_recursions;
+};
+
+DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
+
+#define __debug_atomic_inc(ptr)                                 \
+        this_cpu_inc(lockdep_stats.ptr);
+
+#define debug_atomic_inc(ptr)                   {               \
+        WARN_ON_ONCE(!irqs_disabled());                         \
+        __this_cpu_inc(lockdep_stats.ptr);                      \
+}
+
+#define debug_atomic_dec(ptr)                   {               \
+        WARN_ON_ONCE(!irqs_disabled());                         \
+        __this_cpu_dec(lockdep_stats.ptr);                      \
+}
+
+#define debug_atomic_read(ptr)          ({                              \
+        struct lockdep_stats *__cpu_lockdep_stats;                      \
+        unsigned long long __total = 0;                                 \
+        int __cpu;                                                      \
+        for_each_possible_cpu(__cpu) {                                  \
+                __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu);   \
+                __total += __cpu_lockdep_stats->ptr;                    \
+        }                                                               \
+        __total;                                                        \
+})
 #else
+# define __debug_atomic_inc(ptr)        do { } while (0)
 # define debug_atomic_inc(ptr)          do { } while (0)
 # define debug_atomic_dec(ptr)          do { } while (0)
 # define debug_atomic_read(ptr)         0
diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index d4aba4f3584c..59b76c8ce9d7 100644
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -184,34 +184,34 @@ static const struct file_operations proc_lockdep_chains_operations = {
 static void lockdep_stats_debug_show(struct seq_file *m)
 {
 #ifdef CONFIG_DEBUG_LOCKDEP
-        unsigned int hi1 = debug_atomic_read(&hardirqs_on_events),
-                     hi2 = debug_atomic_read(&hardirqs_off_events),
-                     hr1 = debug_atomic_read(&redundant_hardirqs_on),
-                     hr2 = debug_atomic_read(&redundant_hardirqs_off),
-                     si1 = debug_atomic_read(&softirqs_on_events),
-                     si2 = debug_atomic_read(&softirqs_off_events),
-                     sr1 = debug_atomic_read(&redundant_softirqs_on),
-                     sr2 = debug_atomic_read(&redundant_softirqs_off);
-
-        seq_printf(m, " chain lookup misses:           %11u\n",
-                debug_atomic_read(&chain_lookup_misses));
-        seq_printf(m, " chain lookup hits:             %11u\n",
-                debug_atomic_read(&chain_lookup_hits));
-        seq_printf(m, " cyclic checks:                 %11u\n",
-                debug_atomic_read(&nr_cyclic_checks));
-        seq_printf(m, " find-mask forwards checks:     %11u\n",
-                debug_atomic_read(&nr_find_usage_forwards_checks));
-        seq_printf(m, " find-mask backwards checks:    %11u\n",
-                debug_atomic_read(&nr_find_usage_backwards_checks));
-
-        seq_printf(m, " hardirq on events:             %11u\n", hi1);
-        seq_printf(m, " hardirq off events:            %11u\n", hi2);
-        seq_printf(m, " redundant hardirq ons:         %11u\n", hr1);
-        seq_printf(m, " redundant hardirq offs:        %11u\n", hr2);
-        seq_printf(m, " softirq on events:             %11u\n", si1);
-        seq_printf(m, " softirq off events:            %11u\n", si2);
-        seq_printf(m, " redundant softirq ons:         %11u\n", sr1);
-        seq_printf(m, " redundant softirq offs:        %11u\n", sr2);
+        unsigned long long hi1 = debug_atomic_read(hardirqs_on_events),
+                           hi2 = debug_atomic_read(hardirqs_off_events),
+                           hr1 = debug_atomic_read(redundant_hardirqs_on),
+                           hr2 = debug_atomic_read(redundant_hardirqs_off),
+                           si1 = debug_atomic_read(softirqs_on_events),
+                           si2 = debug_atomic_read(softirqs_off_events),
+                           sr1 = debug_atomic_read(redundant_softirqs_on),
+                           sr2 = debug_atomic_read(redundant_softirqs_off);
+
+        seq_printf(m, " chain lookup misses:           %11llu\n",
+                debug_atomic_read(chain_lookup_misses));
+        seq_printf(m, " chain lookup hits:             %11llu\n",
+                debug_atomic_read(chain_lookup_hits));
+        seq_printf(m, " cyclic checks:                 %11llu\n",
+                debug_atomic_read(nr_cyclic_checks));
+        seq_printf(m, " find-mask forwards checks:     %11llu\n",
+                debug_atomic_read(nr_find_usage_forwards_checks));
+        seq_printf(m, " find-mask backwards checks:    %11llu\n",
+                debug_atomic_read(nr_find_usage_backwards_checks));
+
+        seq_printf(m, " hardirq on events:             %11llu\n", hi1);
+        seq_printf(m, " hardirq off events:            %11llu\n", hi2);
+        seq_printf(m, " redundant hardirq ons:         %11llu\n", hr1);
+        seq_printf(m, " redundant hardirq offs:        %11llu\n", hr2);
+        seq_printf(m, " softirq on events:             %11llu\n", si1);
+        seq_printf(m, " softirq off events:            %11llu\n", si2);
+        seq_printf(m, " redundant softirq ons:         %11llu\n", sr1);
+        seq_printf(m, " redundant softirq offs:        %11llu\n", sr2);
 #endif
 }
 
@@ -263,7 +263,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
 #endif
         }
 #ifdef CONFIG_DEBUG_LOCKDEP
-        DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);
+        DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
 #endif
         seq_printf(m, " lock-classes:                  %11lu [max: %lu]\n",
                         nr_lock_classes, MAX_LOCKDEP_KEYS);
diff --git a/kernel/module.c b/kernel/module.c
index 1016b75b026a..333fbcc96978 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -59,8 +59,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/module.h>
 
-EXPORT_TRACEPOINT_SYMBOL(module_get);
-
 #if 0
 #define DEBUGP printk
 #else
@@ -79,6 +77,10 @@ EXPORT_TRACEPOINT_SYMBOL(module_get);
 DEFINE_MUTEX(module_mutex);
 EXPORT_SYMBOL_GPL(module_mutex);
 static LIST_HEAD(modules);
+#ifdef CONFIG_KGDB_KDB
+struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+#endif /* CONFIG_KGDB_KDB */
+
 
 /* Block module loading/unloading? */
 int modules_disabled = 0;
@@ -178,8 +180,6 @@ extern const struct kernel_symbol __start___ksymtab_gpl[];
 extern const struct kernel_symbol __stop___ksymtab_gpl[];
 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
-extern const struct kernel_symbol __start___ksymtab_gpl_future[];
-extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
 extern const unsigned long __start___kcrctab[];
 extern const unsigned long __start___kcrctab_gpl[];
 extern const unsigned long __start___kcrctab_gpl_future[];
@@ -515,6 +515,9 @@ MODINFO_ATTR(srcversion);
 static char last_unloaded_module[MODULE_NAME_LEN+1];
 
 #ifdef CONFIG_MODULE_UNLOAD
+
+EXPORT_TRACEPOINT_SYMBOL(module_get);
+
 /* Init the unload section of the module. */
 static void module_unload_init(struct module *mod)
 {
@@ -723,16 +726,8 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
                 return -EFAULT;
         name[MODULE_NAME_LEN-1] = '\0';
 
-        /* Create stop_machine threads since free_module relies on
-         * a non-failing stop_machine call. */
-        ret = stop_machine_create();
-        if (ret)
-                return ret;
-
-        if (mutex_lock_interruptible(&module_mutex) != 0) {
-                ret = -EINTR;
-                goto out_stop;
-        }
+        if (mutex_lock_interruptible(&module_mutex) != 0)
+                return -EINTR;
 
         mod = find_module(name);
         if (!mod) {
@@ -792,8 +787,6 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 
  out:
         mutex_unlock(&module_mutex);
-out_stop:
-        stop_machine_destroy();
         return ret;
 }
 
@@ -867,8 +860,7 @@ void module_put(struct module *module)
                 smp_wmb(); /* see comment in module_refcount */
                 __this_cpu_inc(module->refptr->decs);
 
-                trace_module_put(module, _RET_IP_,
-                                 __this_cpu_read(module->refptr->decs));
+                trace_module_put(module, _RET_IP_);
                 /* Maybe they're waiting for us to drop reference? */
                 if (unlikely(!module_is_live(module)))
                         wake_up_process(module->waiter);
@@ -1192,7 +1184,7 @@ struct module_notes_attrs {
         struct bin_attribute attrs[0];
 };
 
-static ssize_t module_notes_read(struct kobject *kobj,
+static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
                                  struct bin_attribute *bin_attr,
                                  char *buf, loff_t pos, size_t count)
 {
diff --git a/kernel/padata.c b/kernel/padata.c
index fd03513c7327..fdd8ae609ce3 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -29,7 +29,7 @@
 #include <linux/rcupdate.h>
 
 #define MAX_SEQ_NR INT_MAX - NR_CPUS
-#define MAX_OBJ_NUM 10000 * NR_CPUS
+#define MAX_OBJ_NUM 1000
 
 static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
 {
@@ -88,7 +88,7 @@ static void padata_parallel_worker(struct work_struct *work)
         local_bh_enable();
 }
 
-/*
+/**
  * padata_do_parallel - padata parallelization function
  *
  * @pinst: padata instance
@@ -152,6 +152,23 @@ out:
 }
 EXPORT_SYMBOL(padata_do_parallel);
 
+/*
+ * padata_get_next - Get the next object that needs serialization.
+ *
+ * Return values are:
+ *
+ * A pointer to the control struct of the next object that needs
+ * serialization, if present in one of the percpu reorder queues.
+ *
+ * NULL, if all percpu reorder queues are empty.
+ *
+ * -EINPROGRESS, if the next object that needs serialization will
+ *  be parallel processed by another cpu and is not yet present in
+ *  the cpu's reorder queue.
+ *
+ * -ENODATA, if this cpu has to do the parallel processing for
+ *  the next object.
+ */
 static struct padata_priv *padata_get_next(struct parallel_data *pd)
 {
         int cpu, num_cpus, empty, calc_seq_nr;
@@ -173,7 +190,7 @@ static struct padata_priv *padata_get_next(struct parallel_data *pd)
 
                 /*
                  * Calculate the seq_nr of the object that should be
-                 * next in this queue.
+                 * next in this reorder queue.
                  */
                 overrun = 0;
                 calc_seq_nr = (atomic_read(&queue->num_obj) * num_cpus)
@@ -231,7 +248,8 @@ static struct padata_priv *padata_get_next(struct parallel_data *pd)
                 goto out;
         }
 
-        if (next_nr % num_cpus == next_queue->cpu_index) {
+        queue = per_cpu_ptr(pd->queue, smp_processor_id());
+        if (queue->cpu_index == next_queue->cpu_index) {
                 padata = ERR_PTR(-ENODATA);
                 goto out;
         }
@@ -247,19 +265,40 @@ static void padata_reorder(struct parallel_data *pd)
         struct padata_queue *queue;
         struct padata_instance *pinst = pd->pinst;
 
-try_again:
+        /*
+         * We need to ensure that only one cpu can work on dequeueing of
+         * the reorder queue the time. Calculating in which percpu reorder
+         * queue the next object will arrive takes some time. A spinlock
+         * would be highly contended. Also it is not clear in which order
+         * the objects arrive to the reorder queues. So a cpu could wait to
+         * get the lock just to notice that there is nothing to do at the
+         * moment. Therefore we use a trylock and let the holder of the lock
+         * care for all the objects enqueued during the holdtime of the lock.
+         */
         if (!spin_trylock_bh(&pd->lock))
-                goto out;
+                return;
 
         while (1) {
                 padata = padata_get_next(pd);
 
+                /*
+                 * All reorder queues are empty, or the next object that needs
+                 * serialization is parallel processed by another cpu and is
+                 * still on it's way to the cpu's reorder queue, nothing to
+                 * do for now.
+                 */
                 if (!padata || PTR_ERR(padata) == -EINPROGRESS)
                         break;
 
+                /*
+                 * This cpu has to do the parallel processing of the next
+                 * object. It's waiting in the cpu's parallelization queue,
+                 * so exit imediately.
+                 */
                 if (PTR_ERR(padata) == -ENODATA) {
+                        del_timer(&pd->timer);
                         spin_unlock_bh(&pd->lock);
-                        goto out;
+                        return;
                 }
 
                 queue = per_cpu_ptr(pd->queue, padata->cb_cpu);
@@ -273,13 +312,27 @@ try_again:
 
         spin_unlock_bh(&pd->lock);
 
-        if (atomic_read(&pd->reorder_objects))
-                goto try_again;
+        /*
+         * The next object that needs serialization might have arrived to
+         * the reorder queues in the meantime, we will be called again
+         * from the timer function if noone else cares for it.
+         */
+        if (atomic_read(&pd->reorder_objects)
+                        && !(pinst->flags & PADATA_RESET))
+                mod_timer(&pd->timer, jiffies + HZ);
+        else
+                del_timer(&pd->timer);
 
-out:
         return;
 }
 
+static void padata_reorder_timer(unsigned long arg)
+{
+        struct parallel_data *pd = (struct parallel_data *)arg;
+
+        padata_reorder(pd);
+}
+
 static void padata_serial_worker(struct work_struct *work)
 {
         struct padata_queue *queue;
@@ -308,7 +361,7 @@ static void padata_serial_worker(struct work_struct *work)
         local_bh_enable();
 }
 
-/*
+/**
  * padata_do_serial - padata serialization function
  *
  * @padata: object to be serialized.
@@ -338,6 +391,7 @@ void padata_do_serial(struct padata_priv *padata)
 }
 EXPORT_SYMBOL(padata_do_serial);
 
+/* Allocate and initialize the internal cpumask dependend resources. */
 static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
                                              const struct cpumask *cpumask)
 {
@@ -358,17 +412,15 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
         if (!alloc_cpumask_var(&pd->cpumask, GFP_KERNEL))
                 goto err_free_queue;
 
-        for_each_possible_cpu(cpu) {
+        cpumask_and(pd->cpumask, cpumask, cpu_active_mask);
+
+        for_each_cpu(cpu, pd->cpumask) {
                 queue = per_cpu_ptr(pd->queue, cpu);
 
                 queue->pd = pd;
 
-                if (cpumask_test_cpu(cpu, cpumask)
-                    && cpumask_test_cpu(cpu, cpu_active_mask)) {
-                        queue->cpu_index = cpu_index;
-                        cpu_index++;
-                } else
-                        queue->cpu_index = -1;
+                queue->cpu_index = cpu_index;
+                cpu_index++;
 
                 INIT_LIST_HEAD(&queue->reorder.list);
                 INIT_LIST_HEAD(&queue->parallel.list);
@@ -382,11 +434,10 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
                 atomic_set(&queue->num_obj, 0);
         }
 
-        cpumask_and(pd->cpumask, cpumask, cpu_active_mask);
-
         num_cpus = cpumask_weight(pd->cpumask);
         pd->max_seq_nr = (MAX_SEQ_NR / num_cpus) * num_cpus - 1;
 
+        setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
         atomic_set(&pd->seq_nr, -1);
         atomic_set(&pd->reorder_objects, 0);
         atomic_set(&pd->refcnt, 0);
@@ -410,6 +461,31 @@ static void padata_free_pd(struct parallel_data *pd)
         kfree(pd);
 }
 
+/* Flush all objects out of the padata queues. */
+static void padata_flush_queues(struct parallel_data *pd)
+{
+        int cpu;
+        struct padata_queue *queue;
+
+        for_each_cpu(cpu, pd->cpumask) {
+                queue = per_cpu_ptr(pd->queue, cpu);
+                flush_work(&queue->pwork);
+        }
+
+        del_timer_sync(&pd->timer);
+
+        if (atomic_read(&pd->reorder_objects))
+                padata_reorder(pd);
+
+        for_each_cpu(cpu, pd->cpumask) {
+                queue = per_cpu_ptr(pd->queue, cpu);
+                flush_work(&queue->swork);
+        }
+
+        BUG_ON(atomic_read(&pd->refcnt) != 0);
+}
+
+/* Replace the internal control stucture with a new one. */
 static void padata_replace(struct padata_instance *pinst,
                            struct parallel_data *pd_new)
 {
@@ -421,17 +497,13 @@ static void padata_replace(struct padata_instance *pinst,
 
         synchronize_rcu();
 
-        while (atomic_read(&pd_old->refcnt) != 0)
-                yield();
-
-        flush_workqueue(pinst->wq);
-
+        padata_flush_queues(pd_old);
         padata_free_pd(pd_old);
 
         pinst->flags &= ~PADATA_RESET;
 }
 
-/*
+/**
  * padata_set_cpumask - set the cpumask that padata should use
  *
  * @pinst: padata instance
@@ -443,10 +515,10 @@ int padata_set_cpumask(struct padata_instance *pinst,
         struct parallel_data *pd;
         int err = 0;
 
-        might_sleep();
-
         mutex_lock(&pinst->lock);
 
+        get_online_cpus();
+
         pd = padata_alloc_pd(pinst, cpumask);
         if (!pd) {
                 err = -ENOMEM;
@@ -458,6 +530,8 @@ int padata_set_cpumask(struct padata_instance *pinst,
         padata_replace(pinst, pd);
 
 out:
+        put_online_cpus();
+
         mutex_unlock(&pinst->lock);
 
         return err;
@@ -479,7 +553,7 @@ static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
         return 0;
 }
 
-/*
+/**
  * padata_add_cpu - add a cpu to the padata cpumask
  *
  * @pinst: padata instance
@@ -489,12 +563,12 @@ int padata_add_cpu(struct padata_instance *pinst, int cpu)
 {
         int err;
 
-        might_sleep();
-
         mutex_lock(&pinst->lock);
 
+        get_online_cpus();
         cpumask_set_cpu(cpu, pinst->cpumask);
         err = __padata_add_cpu(pinst, cpu);
+        put_online_cpus();
 
         mutex_unlock(&pinst->lock);
 
@@ -517,7 +591,7 @@ static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
         return 0;
 }
 
-/*
+/**
  * padata_remove_cpu - remove a cpu from the padata cpumask
  *
  * @pinst: padata instance
@@ -527,12 +601,12 @@ int padata_remove_cpu(struct padata_instance *pinst, int cpu)
 {
         int err;
 
-        might_sleep();
-
         mutex_lock(&pinst->lock);
 
+        get_online_cpus();
         cpumask_clear_cpu(cpu, pinst->cpumask);
         err = __padata_remove_cpu(pinst, cpu);
+        put_online_cpus();
 
         mutex_unlock(&pinst->lock);
 
@@ -540,38 +614,35 @@ int padata_remove_cpu(struct padata_instance *pinst, int cpu)
 }
 EXPORT_SYMBOL(padata_remove_cpu);
 
-/*
+/**
  * padata_start - start the parallel processing
  *
  * @pinst: padata instance to start
  */
 void padata_start(struct padata_instance *pinst)
 {
-        might_sleep();
-
         mutex_lock(&pinst->lock);
         pinst->flags |= PADATA_INIT;
         mutex_unlock(&pinst->lock);
 }
 EXPORT_SYMBOL(padata_start);
 
-/*
+/**
  * padata_stop - stop the parallel processing
  *
  * @pinst: padata instance to stop
  */
 void padata_stop(struct padata_instance *pinst)
 {
-        might_sleep();
-
         mutex_lock(&pinst->lock);
         pinst->flags &= ~PADATA_INIT;
         mutex_unlock(&pinst->lock);
 }
 EXPORT_SYMBOL(padata_stop);
 
-static int __cpuinit padata_cpu_callback(struct notifier_block *nfb,
-                                         unsigned long action, void *hcpu)
+#ifdef CONFIG_HOTPLUG_CPU
+static int padata_cpu_callback(struct notifier_block *nfb,
+                               unsigned long action, void *hcpu)
 {
         int err;
         struct padata_instance *pinst;
@@ -588,7 +659,7 @@ static int __cpuinit padata_cpu_callback(struct notifier_block *nfb,
                 err = __padata_add_cpu(pinst, cpu);
                 mutex_unlock(&pinst->lock);
                 if (err)
-                        return NOTIFY_BAD;
+                        return notifier_from_errno(err);
                 break;
 
         case CPU_DOWN_PREPARE:
@@ -599,7 +670,7 @@ static int __cpuinit padata_cpu_callback(struct notifier_block *nfb,
                 err = __padata_remove_cpu(pinst, cpu);
                 mutex_unlock(&pinst->lock);
                 if (err)
-                        return NOTIFY_BAD;
+                        return notifier_from_errno(err);
                 break;
 
         case CPU_UP_CANCELED:
@@ -621,8 +692,9 @@ static int __cpuinit padata_cpu_callback(struct notifier_block *nfb,
 
         return NOTIFY_OK;
 }
+#endif
 
-/*
+/**
  * padata_alloc - allocate and initialize a padata instance
  *
  * @cpumask: cpumask that padata uses for parallelization
@@ -631,7 +703,6 @@ static int __cpuinit padata_cpu_callback(struct notifier_block *nfb,
 struct padata_instance *padata_alloc(const struct cpumask *cpumask,
                                      struct workqueue_struct *wq)
 {
-        int err;
         struct padata_instance *pinst;
         struct parallel_data *pd;
 
@@ -639,6 +710,8 @@ struct padata_instance *padata_alloc(const struct cpumask *cpumask,
         if (!pinst)
                 goto err;
 
+        get_online_cpus();
+
         pd = padata_alloc_pd(pinst, cpumask);
         if (!pd)
                 goto err_free_inst;
@@ -654,31 +727,32 @@ struct padata_instance *padata_alloc(const struct cpumask *cpumask,
 
         pinst->flags = 0;
 
+#ifdef CONFIG_HOTPLUG_CPU
         pinst->cpu_notifier.notifier_call = padata_cpu_callback;
         pinst->cpu_notifier.priority = 0;
-        err = register_hotcpu_notifier(&pinst->cpu_notifier);
-        if (err)
-                goto err_free_cpumask;
+        register_hotcpu_notifier(&pinst->cpu_notifier);
+#endif
+
+        put_online_cpus();
 
         mutex_init(&pinst->lock);
 
         return pinst;
 
-err_free_cpumask:
-        free_cpumask_var(pinst->cpumask);
 err_free_pd:
         padata_free_pd(pd);
 err_free_inst:
         kfree(pinst);
+        put_online_cpus();
 err:
         return NULL;
 }
 EXPORT_SYMBOL(padata_alloc);
 
-/*
+/**
  * padata_free - free a padata instance
  *
- * @ padata_inst: padata instance to free
+ * @padata_inst: padata instance to free
  */
 void padata_free(struct padata_instance *pinst)
 {
@@ -686,10 +760,13 @@ void padata_free(struct padata_instance *pinst)
 
         synchronize_rcu();
 
-        while (atomic_read(&pinst->pd->refcnt) != 0)
-                yield();
-
+#ifdef CONFIG_HOTPLUG_CPU
         unregister_hotcpu_notifier(&pinst->cpu_notifier);
+#endif
+        get_online_cpus();
+        padata_flush_queues(pinst->pd);
+        put_online_cpus();
+
         padata_free_pd(pinst->pd);
         free_cpumask_var(pinst->cpumask);
         kfree(pinst);
diff --git a/kernel/panic.c b/kernel/panic.c
index 13d966b4c14a..3b16cd93fa7d 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -87,6 +87,7 @@ NORET_TYPE void panic(const char * fmt, ...)
          */
         preempt_disable();
 
+        console_verbose();
         bust_spinlocks(1);
         va_start(args, fmt);
         vsnprintf(buf, sizeof(buf), fmt, args);
@@ -178,6 +179,7 @@ static const struct tnt tnts[] = {
         { TAINT_OVERRIDDEN_ACPI_TABLE,  'A', ' ' },
         { TAINT_WARN,                   'W', ' ' },
         { TAINT_CRAP,                   'C', ' ' },
+        { TAINT_FIRMWARE_WORKAROUND,    'I', ' ' },
 };
 
 /**
@@ -194,6 +196,7 @@ static const struct tnt tnts[] = {
  *  'A' - ACPI table overridden.
  *  'W' - Taint on warning.
  *  'C' - modules from drivers/staging are loaded.
+ *  'I' - Working around severe firmware bug.
  *
  *      The string is overwritten by the next call to print_tainted().
  */
@@ -365,7 +368,8 @@ struct slowpath_args {
         va_list args;
 };
 
-static void warn_slowpath_common(const char *file, int line, void *caller, struct slowpath_args *args)
+static void warn_slowpath_common(const char *file, int line, void *caller,
+                                 unsigned taint, struct slowpath_args *args)
 {
         const char *board;
 
@@ -381,7 +385,7 @@ static void warn_slowpath_common(const char *file, int line, void *caller, struc
         print_modules();
         dump_stack();
         print_oops_end_marker();
-        add_taint(TAINT_WARN);
+        add_taint(taint);
 }
 
 void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
@@ -390,14 +394,29 @@ void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
 
         args.fmt = fmt;
         va_start(args.args, fmt);
-        warn_slowpath_common(file, line, __builtin_return_address(0), &args);
+        warn_slowpath_common(file, line, __builtin_return_address(0),
+                             TAINT_WARN, &args);
         va_end(args.args);
 }
 EXPORT_SYMBOL(warn_slowpath_fmt);
 
+void warn_slowpath_fmt_taint(const char *file, int line,
+                             unsigned taint, const char *fmt, ...)
+{
+        struct slowpath_args args;
+
+        args.fmt = fmt;
+        va_start(args.args, fmt);
+        warn_slowpath_common(file, line, __builtin_return_address(0),
+                             taint, &args);
+        va_end(args.args);
+}
+EXPORT_SYMBOL(warn_slowpath_fmt_taint);
+
 void warn_slowpath_null(const char *file, int line)
 {
-        warn_slowpath_common(file, line, __builtin_return_address(0), NULL);
+        warn_slowpath_common(file, line, __builtin_return_address(0),
+                             TAINT_WARN, NULL);
 }
 EXPORT_SYMBOL(warn_slowpath_null);
 #endif
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 3d1552d3c12b..a4fa381db3c2 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -16,6 +16,7 @@
 #include <linux/file.h>
 #include <linux/poll.h>
 #include <linux/slab.h>
+#include <linux/hash.h>
 #include <linux/sysfs.h>
 #include <linux/dcache.h>
 #include <linux/percpu.h>
@@ -82,14 +83,6 @@ extern __weak const struct pmu *hw_perf_event_init(struct perf_event *event)
 void __weak hw_perf_disable(void)               { barrier(); }
 void __weak hw_perf_enable(void)                { barrier(); }
 
-int __weak
-hw_perf_group_sched_in(struct perf_event *group_leader,
-               struct perf_cpu_context *cpuctx,
-               struct perf_event_context *ctx)
-{
-        return 0;
-}
-
 void __weak perf_event_print_debug(void)        { }
 
 static DEFINE_PER_CPU(int, perf_disable_count);
@@ -262,6 +255,18 @@ static void update_event_times(struct perf_event *event)
         event->total_time_running = run_end - event->tstamp_running;
 }
 
+/*
+ * Update total_time_enabled and total_time_running for all events in a group.
+ */
+static void update_group_times(struct perf_event *leader)
+{
+        struct perf_event *event;
+
+        update_event_times(leader);
+        list_for_each_entry(event, &leader->sibling_list, group_entry)
+                update_event_times(event);
+}
+
 static struct list_head *
 ctx_group_list(struct perf_event *event, struct perf_event_context *ctx)
 {
@@ -315,8 +320,6 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
 static void
 list_del_event(struct perf_event *event, struct perf_event_context *ctx)
 {
-        struct perf_event *sibling, *tmp;
-
         if (list_empty(&event->group_entry))
                 return;
         ctx->nr_events--;
@@ -329,7 +332,7 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
         if (event->group_leader != event)
                 event->group_leader->nr_siblings--;
 
-        update_event_times(event);
+        update_group_times(event);
 
         /*
          * If event was in error state, then keep it
@@ -340,6 +343,12 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
          */
         if (event->state > PERF_EVENT_STATE_OFF)
                 event->state = PERF_EVENT_STATE_OFF;
+}
+
+static void
+perf_destroy_group(struct perf_event *event, struct perf_event_context *ctx)
+{
+        struct perf_event *sibling, *tmp;
 
         /*
          * If this was a group event with sibling events then
@@ -505,18 +514,6 @@ retry:
 }
 
 /*
- * Update total_time_enabled and total_time_running for all events in a group.
- */
-static void update_group_times(struct perf_event *leader)
-{
-        struct perf_event *event;
-
-        update_event_times(leader);
-        list_for_each_entry(event, &leader->sibling_list, group_entry)
-                update_event_times(event);
-}
-
-/*
  * Cross CPU call to disable a performance event
  */
 static void __perf_event_disable(void *info)
@@ -640,15 +637,20 @@ group_sched_in(struct perf_event *group_event,
                struct perf_cpu_context *cpuctx,
                struct perf_event_context *ctx)
 {
-        struct perf_event *event, *partial_group;
+        struct perf_event *event, *partial_group = NULL;
+        const struct pmu *pmu = group_event->pmu;
+        bool txn = false;
         int ret;
 
         if (group_event->state == PERF_EVENT_STATE_OFF)
                 return 0;
 
-        ret = hw_perf_group_sched_in(group_event, cpuctx, ctx);
-        if (ret)
-                return ret < 0 ? ret : 0;
+        /* Check if group transaction availabe */
+        if (pmu->start_txn)
+                txn = true;
+
+        if (txn)
+                pmu->start_txn(pmu);
 
         if (event_sched_in(group_event, cpuctx, ctx))
                 return -EAGAIN;
@@ -663,9 +665,19 @@ group_sched_in(struct perf_event *group_event,
                 }
         }
 
-        return 0;
+        if (!txn)
+                return 0;
+
+        ret = pmu->commit_txn(pmu);
+        if (!ret) {
+                pmu->cancel_txn(pmu);
+                return 0;
+        }
 
 group_error:
+        if (txn)
+                pmu->cancel_txn(pmu);
+
         /*
          * Groups can be scheduled in as one unit only, so undo any
          * partial group before returning:
@@ -1367,6 +1379,8 @@ void perf_event_task_sched_in(struct task_struct *task)
         if (cpuctx->task_ctx == ctx)
                 return;
 
+        perf_disable();
+
         /*
          * We want to keep the following priority order:
          * cpu pinned (that don't need to move), task pinned,
@@ -1379,6 +1393,8 @@ void perf_event_task_sched_in(struct task_struct *task)
         ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE);
 
         cpuctx->task_ctx = ctx;
+
+        perf_enable();
 }
 
 #define MAX_INTERRUPTS (~0ULL)
@@ -1856,9 +1872,30 @@ int perf_event_release_kernel(struct perf_event *event)
 {
         struct perf_event_context *ctx = event->ctx;
 
+        /*
+         * Remove from the PMU, can't get re-enabled since we got
+         * here because the last ref went.
+         */
+        perf_event_disable(event);
+
         WARN_ON_ONCE(ctx->parent_ctx);
-        mutex_lock(&ctx->mutex);
-        perf_event_remove_from_context(event);
+        /*
+         * There are two ways this annotation is useful:
+         *
+         *  1) there is a lock recursion from perf_event_exit_task
+         *     see the comment there.
+         *
+         *  2) there is a lock-inversion with mmap_sem through
+         *     perf_event_read_group(), which takes faults while
+         *     holding ctx->mutex, however this is called after
+         *     the last filedesc died, so there is no possibility
+         *     to trigger the AB-BA case.
+         */
+        mutex_lock_nested(&ctx->mutex, SINGLE_DEPTH_NESTING);
+        raw_spin_lock_irq(&ctx->lock);
+        list_del_event(event, ctx);
+        perf_destroy_group(event, ctx);
+        raw_spin_unlock_irq(&ctx->lock);
         mutex_unlock(&ctx->mutex);
 
         mutex_lock(&event->owner->perf_event_mutex);
@@ -2642,6 +2679,7 @@ static int perf_fasync(int fd, struct file *filp, int on)
 }
 
 static const struct file_operations perf_fops = {
+        .llseek                 = no_llseek,
         .release                = perf_release,
         .read                   = perf_read,
         .poll                   = perf_poll,
@@ -2792,6 +2830,27 @@ void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int ski
 
 
 /*
+ * We assume there is only KVM supporting the callbacks.
+ * Later on, we might change it to a list if there is
+ * another virtualization implementation supporting the callbacks.
+ */
+struct perf_guest_info_callbacks *perf_guest_cbs;
+
+int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs)
+{
+        perf_guest_cbs = cbs;
+        return 0;
+}
+EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks);
+
+int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs)
+{
+        perf_guest_cbs = NULL;
+        return 0;
+}
+EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks);
+
+/*
  * Output
  */
 static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
@@ -3743,7 +3802,7 @@ void __perf_event_mmap(struct vm_area_struct *vma)
                 .event_id  = {
                         .header = {
                                 .type = PERF_RECORD_MMAP,
-                                .misc = 0,
+                                .misc = PERF_RECORD_MISC_USER,
                                 /* .size */
                         },
                         /* .pid */
@@ -3961,36 +4020,6 @@ static void perf_swevent_add(struct perf_event *event, u64 nr,
         perf_swevent_overflow(event, 0, nmi, data, regs);
 }
 
-static int perf_swevent_is_counting(struct perf_event *event)
-{
-        /*
-         * The event is active, we're good!
-         */
-        if (event->state == PERF_EVENT_STATE_ACTIVE)
-                return 1;
-
-        /*
-         * The event is off/error, not counting.
-         */
-        if (event->state != PERF_EVENT_STATE_INACTIVE)
-                return 0;
-
-        /*
-         * The event is inactive, if the context is active
-         * we're part of a group that didn't make it on the 'pmu',
-         * not counting.
-         */
-        if (event->ctx->is_active)
-                return 0;
-
-        /*
-         * We're inactive and the context is too, this means the
-         * task is scheduled out, we're counting events that happen
-         * to us, like migration events.
-         */
-        return 1;
-}
-
 static int perf_tp_event_match(struct perf_event *event,
                                 struct perf_sample_data *data);
 
@@ -4014,12 +4043,6 @@ static int perf_swevent_match(struct perf_event *event,
                                 struct perf_sample_data *data,
                                 struct pt_regs *regs)
 {
-        if (event->cpu != -1 && event->cpu != smp_processor_id())
-                return 0;
-
-        if (!perf_swevent_is_counting(event))
-                return 0;
-
         if (event->attr.type != type)
                 return 0;
 
@@ -4036,18 +4059,53 @@ static int perf_swevent_match(struct perf_event *event,
         return 1;
 }
 
-static void perf_swevent_ctx_event(struct perf_event_context *ctx,
-                                     enum perf_type_id type,
-                                     u32 event_id, u64 nr, int nmi,
-                                     struct perf_sample_data *data,
-                                     struct pt_regs *regs)
+static inline u64 swevent_hash(u64 type, u32 event_id)
 {
+        u64 val = event_id | (type << 32);
+
+        return hash_64(val, SWEVENT_HLIST_BITS);
+}
+
+static struct hlist_head *
+find_swevent_head(struct perf_cpu_context *ctx, u64 type, u32 event_id)
+{
+        u64 hash;
+        struct swevent_hlist *hlist;
+
+        hash = swevent_hash(type, event_id);
+
+        hlist = rcu_dereference(ctx->swevent_hlist);
+        if (!hlist)
+                return NULL;
+
+        return &hlist->heads[hash];
+}
+
+static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
+                                    u64 nr, int nmi,
+                                    struct perf_sample_data *data,
+                                    struct pt_regs *regs)
+{
+        struct perf_cpu_context *cpuctx;
         struct perf_event *event;
+        struct hlist_node *node;
+        struct hlist_head *head;
 
-        list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+        cpuctx = &__get_cpu_var(perf_cpu_context);
+
+        rcu_read_lock();
+
+        head = find_swevent_head(cpuctx, type, event_id);
+
+        if (!head)
+                goto end;
+
+        hlist_for_each_entry_rcu(event, node, head, hlist_entry) {
                 if (perf_swevent_match(event, type, event_id, data, regs))
                         perf_swevent_add(event, nr, nmi, data, regs);
         }
+end:
+        rcu_read_unlock();
 }
 
 int perf_swevent_get_recursion_context(void)
@@ -4085,27 +4143,6 @@ void perf_swevent_put_recursion_context(int rctx)
 }
 EXPORT_SYMBOL_GPL(perf_swevent_put_recursion_context);
 
-static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
-                                    u64 nr, int nmi,
-                                    struct perf_sample_data *data,
-                                    struct pt_regs *regs)
-{
-        struct perf_cpu_context *cpuctx;
-        struct perf_event_context *ctx;
-
-        cpuctx = &__get_cpu_var(perf_cpu_context);
-        rcu_read_lock();
-        perf_swevent_ctx_event(&cpuctx->ctx, type, event_id,
-                                 nr, nmi, data, regs);
-        /*
-         * doesn't really matter which of the child contexts the
-         * events ends up in.
-         */
-        ctx = rcu_dereference(current->perf_event_ctxp);
-        if (ctx)
-                perf_swevent_ctx_event(ctx, type, event_id, nr, nmi, data, regs);
-        rcu_read_unlock();
-}
 
 void __perf_sw_event(u32 event_id, u64 nr, int nmi,
                             struct pt_regs *regs, u64 addr)
@@ -4131,16 +4168,28 @@ static void perf_swevent_read(struct perf_event *event)
 static int perf_swevent_enable(struct perf_event *event)
 {
         struct hw_perf_event *hwc = &event->hw;
+        struct perf_cpu_context *cpuctx;
+        struct hlist_head *head;
+
+        cpuctx = &__get_cpu_var(perf_cpu_context);
 
         if (hwc->sample_period) {
                 hwc->last_period = hwc->sample_period;
                 perf_swevent_set_period(event);
         }
+
+        head = find_swevent_head(cpuctx, event->attr.type, event->attr.config);
+        if (WARN_ON_ONCE(!head))
+                return -EINVAL;
+
+        hlist_add_head_rcu(&event->hlist_entry, head);
+
         return 0;
 }
 
 static void perf_swevent_disable(struct perf_event *event)
 {
+        hlist_del_rcu(&event->hlist_entry);
 }
 
 static const struct pmu perf_ops_generic = {
@@ -4168,15 +4217,8 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
         perf_sample_data_init(&data, 0);
         data.period = event->hw.last_period;
         regs = get_irq_regs();
-        /*
-         * In case we exclude kernel IPs or are somehow not in interrupt
-         * context, provide the next best thing, the user IP.
-         */
-        if ((event->attr.exclude_kernel || !regs) &&
-                        !event->attr.exclude_user)
-                regs = task_pt_regs(current);
 
-        if (regs) {
+        if (regs && !perf_exclude_event(event, regs)) {
                 if (!(event->attr.exclude_idle && current->pid == 0))
                         if (perf_event_overflow(event, 0, &data, regs))
                                 ret = HRTIMER_NORESTART;
@@ -4324,6 +4366,105 @@ static const struct pmu perf_ops_task_clock = {
         .read           = task_clock_perf_event_read,
 };
 
+static void swevent_hlist_release_rcu(struct rcu_head *rcu_head)
+{
+        struct swevent_hlist *hlist;
+
+        hlist = container_of(rcu_head, struct swevent_hlist, rcu_head);
+        kfree(hlist);
+}
+
+static void swevent_hlist_release(struct perf_cpu_context *cpuctx)
+{
+        struct swevent_hlist *hlist;
+
+        if (!cpuctx->swevent_hlist)
+                return;
+
+        hlist = cpuctx->swevent_hlist;
+        rcu_assign_pointer(cpuctx->swevent_hlist, NULL);
+        call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu);
+}
+
+static void swevent_hlist_put_cpu(struct perf_event *event, int cpu)
+{
+        struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+
+        mutex_lock(&cpuctx->hlist_mutex);
+
+        if (!--cpuctx->hlist_refcount)
+                swevent_hlist_release(cpuctx);
+
+        mutex_unlock(&cpuctx->hlist_mutex);
+}
+
+static void swevent_hlist_put(struct perf_event *event)
+{
+        int cpu;
+
+        if (event->cpu != -1) {
+                swevent_hlist_put_cpu(event, event->cpu);
+                return;
+        }
+
+        for_each_possible_cpu(cpu)
+                swevent_hlist_put_cpu(event, cpu);
+}
+
+static int swevent_hlist_get_cpu(struct perf_event *event, int cpu)
+{
+        struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+        int err = 0;
+
+        mutex_lock(&cpuctx->hlist_mutex);
+
+        if (!cpuctx->swevent_hlist && cpu_online(cpu)) {
+                struct swevent_hlist *hlist;
+
+                hlist = kzalloc(sizeof(*hlist), GFP_KERNEL);
+                if (!hlist) {
+                        err = -ENOMEM;
+                        goto exit;
+                }
+                rcu_assign_pointer(cpuctx->swevent_hlist, hlist);
+        }
+        cpuctx->hlist_refcount++;
+ exit:
+        mutex_unlock(&cpuctx->hlist_mutex);
+
+        return err;
+}
+
+static int swevent_hlist_get(struct perf_event *event)
+{
+        int err;
+        int cpu, failed_cpu;
+
+        if (event->cpu != -1)
+                return swevent_hlist_get_cpu(event, event->cpu);
+
+        get_online_cpus();
+        for_each_possible_cpu(cpu) {
+                err = swevent_hlist_get_cpu(event, cpu);
+                if (err) {
+                        failed_cpu = cpu;
+                        goto fail;
+                }
+        }
+        put_online_cpus();
+
+        return 0;
+ fail:
+        for_each_possible_cpu(cpu) {
+                if (cpu == failed_cpu)
+                        break;
+                swevent_hlist_put_cpu(event, cpu);
+        }
+
+        put_online_cpus();
+        return err;
+}
+
 #ifdef CONFIG_EVENT_TRACING
 
 void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
@@ -4357,10 +4498,13 @@ static int perf_tp_event_match(struct perf_event *event,
 static void tp_perf_event_destroy(struct perf_event *event)
 {
         perf_trace_disable(event->attr.config);
+        swevent_hlist_put(event);
 }
 
 static const struct pmu *tp_perf_event_init(struct perf_event *event)
 {
+        int err;
+
         /*
          * Raw tracepoint data is a severe data leak, only allow root to
          * have these.
@@ -4374,6 +4518,11 @@ static const struct pmu *tp_perf_event_init(struct perf_event *event)
                 return NULL;
 
         event->destroy = tp_perf_event_destroy;
+        err = swevent_hlist_get(event);
+        if (err) {
+                perf_trace_disable(event->attr.config);
+                return ERR_PTR(err);
+        }
 
         return &perf_ops_generic;
 }
@@ -4474,6 +4623,7 @@ static void sw_perf_event_destroy(struct perf_event *event)
         WARN_ON(event->parent);
 
         atomic_dec(&perf_swevent_enabled[event_id]);
+        swevent_hlist_put(event);
 }
 
 static const struct pmu *sw_perf_event_init(struct perf_event *event)
@@ -4512,6 +4662,12 @@ static const struct pmu *sw_perf_event_init(struct perf_event *event)
         case PERF_COUNT_SW_ALIGNMENT_FAULTS:
         case PERF_COUNT_SW_EMULATION_FAULTS:
                 if (!event->parent) {
+                        int err;
+
+                        err = swevent_hlist_get(event);
+                        if (err)
+                                return ERR_PTR(err);
+
                         atomic_inc(&perf_swevent_enabled[event_id]);
                         event->destroy = sw_perf_event_destroy;
                 }
@@ -5176,7 +5332,7 @@ void perf_event_exit_task(struct task_struct *child)
          *
          * But since its the parent context it won't be the same instance.
          */
-        mutex_lock_nested(&child_ctx->mutex, SINGLE_DEPTH_NESTING);
+        mutex_lock(&child_ctx->mutex);
 
 again:
         list_for_each_entry_safe(child_event, tmp, &child_ctx->pinned_groups,
@@ -5384,6 +5540,7 @@ static void __init perf_event_init_all_cpus(void)
 
         for_each_possible_cpu(cpu) {
                 cpuctx = &per_cpu(perf_cpu_context, cpu);
+                mutex_init(&cpuctx->hlist_mutex);
                 __perf_event_init_context(&cpuctx->ctx, NULL);
         }
 }
@@ -5397,6 +5554,16 @@ static void __cpuinit perf_event_init_cpu(int cpu)
         spin_lock(&perf_resource_lock);
         cpuctx->max_pertask = perf_max_events - perf_reserved_percpu;
         spin_unlock(&perf_resource_lock);
+
+        mutex_lock(&cpuctx->hlist_mutex);
+        if (cpuctx->hlist_refcount > 0) {
+                struct swevent_hlist *hlist;
+
+                hlist = kzalloc(sizeof(*hlist), GFP_KERNEL);
+                WARN_ON_ONCE(!hlist);
+                rcu_assign_pointer(cpuctx->swevent_hlist, hlist);
+        }
+        mutex_unlock(&cpuctx->hlist_mutex);
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -5416,6 +5583,10 @@ static void perf_event_exit_cpu(int cpu)
         struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
         struct perf_event_context *ctx = &cpuctx->ctx;
 
+        mutex_lock(&cpuctx->hlist_mutex);
+        swevent_hlist_release(cpuctx);
+        mutex_unlock(&cpuctx->hlist_mutex);
+
         mutex_lock(&ctx->mutex);
         smp_call_function_single(cpu, __perf_event_exit_cpu, NULL, 1);
         mutex_unlock(&ctx->mutex);
diff --git a/kernel/pid.c b/kernel/pid.c
index aebb30d9c233..e9fd8c132d26 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -513,6 +513,13 @@ void __init pidhash_init(void)
 
 void __init pidmap_init(void)
 {
+        /* bump default and minimum pid_max based on number of cpus */
+        pid_max = min(pid_max_max, max_t(int, pid_max,
+                                PIDS_PER_CPU_DEFAULT * num_possible_cpus()));
+        pid_max_min = max_t(int, pid_max_min,
+                                PIDS_PER_CPU_MIN * num_possible_cpus());
+        pr_info("pid_max: default: %u minimum: %u\n", pid_max, pid_max_min);
+
         init_pid_ns.pidmap[0].page = kzalloc(PAGE_SIZE, GFP_KERNEL);
         /* Reserve PID 0. We never call free_pidmap(0) */
         set_bit(0, init_pid_ns.pidmap[0].page);
diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index 3db49b9ca374..f42d3f737a33 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -2,7 +2,7 @@
  * This module exposes the interface to kernel space for specifying
  * QoS dependencies.  It provides infrastructure for registration of:
  *
- * Dependents on a QoS value : register requirements
+ * Dependents on a QoS value : register requests
  * Watchers of QoS value : get notified when target QoS value changes
  *
  * This QoS design is best effort based.  Dependents register their QoS needs.
@@ -14,19 +14,21 @@
  * timeout: usec <-- currently not used.
  * throughput: kbs (kilo byte / sec)
  *
- * There are lists of pm_qos_objects each one wrapping requirements, notifiers
+ * There are lists of pm_qos_objects each one wrapping requests, notifiers
  *
- * User mode requirements on a QOS parameter register themselves to the
+ * User mode requests on a QOS parameter register themselves to the
  * subsystem by opening the device node /dev/... and writing there request to
  * the node.  As long as the process holds a file handle open to the node the
  * client continues to be accounted for.  Upon file release the usermode
- * requirement is removed and a new qos target is computed.  This way when the
- * requirement that the application has is cleaned up when closes the file
+ * request is removed and a new qos target is computed.  This way when the
+ * request that the application has is cleaned up when closes the file
  * pointer or exits the pm_qos_object will get an opportunity to clean up.
  *
  * Mark Gross <mgross@linux.intel.com>
  */
 
+/*#define DEBUG*/
+
 #include <linux/pm_qos_params.h>
 #include <linux/sched.h>
 #include <linux/spinlock.h>
@@ -42,25 +44,25 @@
 #include <linux/uaccess.h>
 
 /*
- * locking rule: all changes to requirements or notifiers lists
+ * locking rule: all changes to requests or notifiers lists
  * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock
  * held, taken with _irqsave.  One lock to rule them all
  */
-struct requirement_list {
+struct pm_qos_request_list {
         struct list_head list;
         union {
                 s32 value;
                 s32 usec;
                 s32 kbps;
         };
-        char *name;
+        int pm_qos_class;
 };
 
 static s32 max_compare(s32 v1, s32 v2);
 static s32 min_compare(s32 v1, s32 v2);
 
 struct pm_qos_object {
-        struct requirement_list requirements;
+        struct pm_qos_request_list requests;
         struct blocking_notifier_head *notifiers;
         struct miscdevice pm_qos_power_miscdev;
         char *name;
@@ -72,7 +74,7 @@ struct pm_qos_object {
 static struct pm_qos_object null_pm_qos;
 static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier);
 static struct pm_qos_object cpu_dma_pm_qos = {
-        .requirements = {LIST_HEAD_INIT(cpu_dma_pm_qos.requirements.list)},
+        .requests = {LIST_HEAD_INIT(cpu_dma_pm_qos.requests.list)},
         .notifiers = &cpu_dma_lat_notifier,
         .name = "cpu_dma_latency",
         .default_value = 2000 * USEC_PER_SEC,
@@ -82,7 +84,7 @@ static struct pm_qos_object cpu_dma_pm_qos = {
 
 static BLOCKING_NOTIFIER_HEAD(network_lat_notifier);
 static struct pm_qos_object network_lat_pm_qos = {
-        .requirements = {LIST_HEAD_INIT(network_lat_pm_qos.requirements.list)},
+        .requests = {LIST_HEAD_INIT(network_lat_pm_qos.requests.list)},
         .notifiers = &network_lat_notifier,
         .name = "network_latency",
         .default_value = 2000 * USEC_PER_SEC,
@@ -93,8 +95,7 @@ static struct pm_qos_object network_lat_pm_qos = {
 
 static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier);
 static struct pm_qos_object network_throughput_pm_qos = {
-        .requirements =
-                {LIST_HEAD_INIT(network_throughput_pm_qos.requirements.list)},
+        .requests = {LIST_HEAD_INIT(network_throughput_pm_qos.requests.list)},
         .notifiers = &network_throughput_notifier,
         .name = "network_throughput",
         .default_value = 0,
@@ -135,31 +136,34 @@ static s32 min_compare(s32 v1, s32 v2)
 }
 
 
-static void update_target(int target)
+static void update_target(int pm_qos_class)
 {
         s32 extreme_value;
-        struct requirement_list *node;
+        struct pm_qos_request_list *node;
         unsigned long flags;
         int call_notifier = 0;
 
         spin_lock_irqsave(&pm_qos_lock, flags);
-        extreme_value = pm_qos_array[target]->default_value;
+        extreme_value = pm_qos_array[pm_qos_class]->default_value;
         list_for_each_entry(node,
-                        &pm_qos_array[target]->requirements.list, list) {
-                extreme_value = pm_qos_array[target]->comparitor(
+                        &pm_qos_array[pm_qos_class]->requests.list, list) {
+                extreme_value = pm_qos_array[pm_qos_class]->comparitor(
                                 extreme_value, node->value);
         }
-        if (atomic_read(&pm_qos_array[target]->target_value) != extreme_value) {
+        if (atomic_read(&pm_qos_array[pm_qos_class]->target_value) !=
+                        extreme_value) {
                 call_notifier = 1;
-                atomic_set(&pm_qos_array[target]->target_value, extreme_value);
-                pr_debug(KERN_ERR "new target for qos %d is %d\n", target,
-                        atomic_read(&pm_qos_array[target]->target_value));
+                atomic_set(&pm_qos_array[pm_qos_class]->target_value,
+                                extreme_value);
+                pr_debug(KERN_ERR "new target for qos %d is %d\n", pm_qos_class,
+                        atomic_read(&pm_qos_array[pm_qos_class]->target_value));
         }
         spin_unlock_irqrestore(&pm_qos_lock, flags);
 
         if (call_notifier)
-                blocking_notifier_call_chain(pm_qos_array[target]->notifiers,
-                        (unsigned long) extreme_value, NULL);
+                blocking_notifier_call_chain(
+                                pm_qos_array[pm_qos_class]->notifiers,
+                                        (unsigned long) extreme_value, NULL);
 }
 
 static int register_pm_qos_misc(struct pm_qos_object *qos)
@@ -185,125 +189,112 @@ static int find_pm_qos_object_by_minor(int minor)
 }
 
 /**
- * pm_qos_requirement - returns current system wide qos expectation
+ * pm_qos_request - returns current system wide qos expectation
  * @pm_qos_class: identification of which qos value is requested
  *
  * This function returns the current target value in an atomic manner.
  */
-int pm_qos_requirement(int pm_qos_class)
+int pm_qos_request(int pm_qos_class)
 {
         return atomic_read(&pm_qos_array[pm_qos_class]->target_value);
 }
-EXPORT_SYMBOL_GPL(pm_qos_requirement);
+EXPORT_SYMBOL_GPL(pm_qos_request);
 
 /**
- * pm_qos_add_requirement - inserts new qos request into the list
+ * pm_qos_add_request - inserts new qos request into the list
  * @pm_qos_class: identifies which list of qos request to us
- * @name: identifies the request
  * @value: defines the qos request
  *
  * This function inserts a new entry in the pm_qos_class list of requested qos
  * performance characteristics.  It recomputes the aggregate QoS expectations
- * for the pm_qos_class of parameters.
+ * for the pm_qos_class of parameters, and returns the pm_qos_request list
+ * element as a handle for use in updating and removal.  Call needs to save
+ * this handle for later use.
  */
-int pm_qos_add_requirement(int pm_qos_class, char *name, s32 value)
+struct pm_qos_request_list *pm_qos_add_request(int pm_qos_class, s32 value)
 {
-        struct requirement_list *dep;
+        struct pm_qos_request_list *dep;
         unsigned long flags;
 
-        dep = kzalloc(sizeof(struct requirement_list), GFP_KERNEL);
+        dep = kzalloc(sizeof(struct pm_qos_request_list), GFP_KERNEL);
         if (dep) {
                 if (value == PM_QOS_DEFAULT_VALUE)
                         dep->value = pm_qos_array[pm_qos_class]->default_value;
                 else
                         dep->value = value;
-                dep->name = kstrdup(name, GFP_KERNEL);
-                if (!dep->name)
-                        goto cleanup;
+                dep->pm_qos_class = pm_qos_class;
 
                 spin_lock_irqsave(&pm_qos_lock, flags);
                 list_add(&dep->list,
-                        &pm_qos_array[pm_qos_class]->requirements.list);
+                        &pm_qos_array[pm_qos_class]->requests.list);
                 spin_unlock_irqrestore(&pm_qos_lock, flags);
                 update_target(pm_qos_class);
-
-                return 0;
         }
 
-cleanup:
-        kfree(dep);
-        return -ENOMEM;
+        return dep;
 }
-EXPORT_SYMBOL_GPL(pm_qos_add_requirement);
+EXPORT_SYMBOL_GPL(pm_qos_add_request);
 
 /**
- * pm_qos_update_requirement - modifies an existing qos request
- * @pm_qos_class: identifies which list of qos request to us
- * @name: identifies the request
+ * pm_qos_update_request - modifies an existing qos request
+ * @pm_qos_req : handle to list element holding a pm_qos request to use
  * @value: defines the qos request
  *
- * Updates an existing qos requirement for the pm_qos_class of parameters along
+ * Updates an existing qos request for the pm_qos_class of parameters along
  * with updating the target pm_qos_class value.
  *
- * If the named request isn't in the list then no change is made.
+ * Attempts are made to make this code callable on hot code paths.
  */
-int pm_qos_update_requirement(int pm_qos_class, char *name, s32 new_value)
+void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req,
+                s32 new_value)
 {
         unsigned long flags;
-        struct requirement_list *node;
         int pending_update = 0;
+        s32 temp;
 
-        spin_lock_irqsave(&pm_qos_lock, flags);
-        list_for_each_entry(node,
-                &pm_qos_array[pm_qos_class]->requirements.list, list) {
-                if (strcmp(node->name, name) == 0) {
-                        if (new_value == PM_QOS_DEFAULT_VALUE)
-                                node->value =
-                                pm_qos_array[pm_qos_class]->default_value;
-                        else
-                                node->value = new_value;
+        if (pm_qos_req) { /*guard against callers passing in null */
+                spin_lock_irqsave(&pm_qos_lock, flags);
+                if (new_value == PM_QOS_DEFAULT_VALUE)
+                        temp = pm_qos_array[pm_qos_req->pm_qos_class]->default_value;
+                else
+                        temp = new_value;
+
+                if (temp != pm_qos_req->value) {
                         pending_update = 1;
-                        break;
+                        pm_qos_req->value = temp;
                 }
+                spin_unlock_irqrestore(&pm_qos_lock, flags);
+                if (pending_update)
+                        update_target(pm_qos_req->pm_qos_class);
         }
-        spin_unlock_irqrestore(&pm_qos_lock, flags);
-        if (pending_update)
-                update_target(pm_qos_class);
-
-        return 0;
 }
-EXPORT_SYMBOL_GPL(pm_qos_update_requirement);
+EXPORT_SYMBOL_GPL(pm_qos_update_request);
 
 /**
- * pm_qos_remove_requirement - modifies an existing qos request
- * @pm_qos_class: identifies which list of qos request to us
- * @name: identifies the request
+ * pm_qos_remove_request - modifies an existing qos request
+ * @pm_qos_req: handle to request list element
  *
- * Will remove named qos request from pm_qos_class list of parameters and
- * recompute the current target value for the pm_qos_class.
+ * Will remove pm qos request from the list of requests and
+ * recompute the current target value for the pm_qos_class.  Call this
+ * on slow code paths.
  */
-void pm_qos_remove_requirement(int pm_qos_class, char *name)
+void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req)
 {
         unsigned long flags;
-        struct requirement_list *node;
-        int pending_update = 0;
+        int qos_class;
 
+        if (pm_qos_req == NULL)
+                return;
+                /* silent return to keep pcm code cleaner */
+
+        qos_class = pm_qos_req->pm_qos_class;
         spin_lock_irqsave(&pm_qos_lock, flags);
-        list_for_each_entry(node,
-                &pm_qos_array[pm_qos_class]->requirements.list, list) {
-                if (strcmp(node->name, name) == 0) {
-                        kfree(node->name);
-                        list_del(&node->list);
-                        kfree(node);
-                        pending_update = 1;
-                        break;
-                }
-        }
+        list_del(&pm_qos_req->list);
+        kfree(pm_qos_req);
         spin_unlock_irqrestore(&pm_qos_lock, flags);
-        if (pending_update)
-                update_target(pm_qos_class);
+        update_target(qos_class);
 }
-EXPORT_SYMBOL_GPL(pm_qos_remove_requirement);
+EXPORT_SYMBOL_GPL(pm_qos_remove_request);
 
 /**
  * pm_qos_add_notifier - sets notification entry for changes to target value
@@ -313,7 +304,7 @@ EXPORT_SYMBOL_GPL(pm_qos_remove_requirement);
  * will register the notifier into a notification chain that gets called
  * upon changes to the pm_qos_class target value.
  */
- int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier)
+int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier)
 {
         int retval;
 
@@ -343,21 +334,16 @@ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier)
 }
 EXPORT_SYMBOL_GPL(pm_qos_remove_notifier);
 
-#define PID_NAME_LEN 32
-
 static int pm_qos_power_open(struct inode *inode, struct file *filp)
 {
-        int ret;
         long pm_qos_class;
-        char name[PID_NAME_LEN];
 
         pm_qos_class = find_pm_qos_object_by_minor(iminor(inode));
         if (pm_qos_class >= 0) {
-                filp->private_data = (void *)pm_qos_class;
-                snprintf(name, PID_NAME_LEN, "process_%d", current->pid);
-                ret = pm_qos_add_requirement(pm_qos_class, name,
-                                        PM_QOS_DEFAULT_VALUE);
-                if (ret >= 0)
+                filp->private_data = (void *) pm_qos_add_request(pm_qos_class,
+                                PM_QOS_DEFAULT_VALUE);
+
+                if (filp->private_data)
                         return 0;
         }
         return -EPERM;
@@ -365,32 +351,40 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp)
 
 static int pm_qos_power_release(struct inode *inode, struct file *filp)
 {
-        int pm_qos_class;
-        char name[PID_NAME_LEN];
+        struct pm_qos_request_list *req;
 
-        pm_qos_class = (long)filp->private_data;
-        snprintf(name, PID_NAME_LEN, "process_%d", current->pid);
-        pm_qos_remove_requirement(pm_qos_class, name);
+        req = (struct pm_qos_request_list *)filp->private_data;
+        pm_qos_remove_request(req);
 
         return 0;
 }
 
+
 static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
                 size_t count, loff_t *f_pos)
 {
         s32 value;
-        int pm_qos_class;
-        char name[PID_NAME_LEN];
-
-        pm_qos_class = (long)filp->private_data;
-        if (count != sizeof(s32))
+        int x;
+        char ascii_value[11];
+        struct pm_qos_request_list *pm_qos_req;
+
+        if (count == sizeof(s32)) {
+                if (copy_from_user(&value, buf, sizeof(s32)))
+                        return -EFAULT;
+        } else if (count == 11) { /* len('0x12345678/0') */
+                if (copy_from_user(ascii_value, buf, 11))
+                        return -EFAULT;
+                x = sscanf(ascii_value, "%x", &value);
+                if (x != 1)
+                        return -EINVAL;
+                pr_debug(KERN_ERR "%s, %d, 0x%x\n", ascii_value, x, value);
+        } else
                 return -EINVAL;
-        if (copy_from_user(&value, buf, sizeof(s32)))
-                return -EFAULT;
-        snprintf(name, PID_NAME_LEN, "process_%d", current->pid);
-        pm_qos_update_requirement(pm_qos_class, name, value);
 
-        return  sizeof(s32);
+        pm_qos_req = (struct pm_qos_request_list *)filp->private_data;
+        pm_qos_update_request(pm_qos_req, value);
+
+        return count;
 }
 
 
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index bc7704b3a443..9829646d399c 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -11,19 +11,18 @@
 #include <trace/events/timer.h>
 
 /*
- * Called after updating RLIMIT_CPU to set timer expiration if necessary.
+ * Called after updating RLIMIT_CPU to run cpu timer and update
+ * tsk->signal->cputime_expires expiration cache if necessary. Needs
+ * siglock protection since other code may update expiration cache as
+ * well.
  */
 void update_rlimit_cpu(unsigned long rlim_new)
 {
         cputime_t cputime = secs_to_cputime(rlim_new);
-        struct signal_struct *const sig = current->signal;
 
-        if (cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) ||
-            cputime_gt(sig->it[CPUCLOCK_PROF].expires, cputime)) {
-                spin_lock_irq(&current->sighand->siglock);
-                set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL);
-                spin_unlock_irq(&current->sighand->siglock);
-        }
+        spin_lock_irq(&current->sighand->siglock);
+        set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL);
+        spin_unlock_irq(&current->sighand->siglock);
 }
 
 static int check_clock(const clockid_t which_clock)
@@ -364,7 +363,7 @@ int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp)
                                 }
                         } else {
                                 read_lock(&tasklist_lock);
-                                if (thread_group_leader(p) && p->signal) {
+                                if (thread_group_leader(p) && p->sighand) {
                                         error =
                                             cpu_clock_sample_group(which_clock,
                                                                    p, &rtn);
@@ -440,7 +439,7 @@ int posix_cpu_timer_del(struct k_itimer *timer)
 
         if (likely(p != NULL)) {
                 read_lock(&tasklist_lock);
-                if (unlikely(p->signal == NULL)) {
+                if (unlikely(p->sighand == NULL)) {
                         /*
                          * We raced with the reaping of the task.
                          * The deletion should have cleared us off the list.
@@ -548,111 +547,62 @@ static inline int expires_gt(cputime_t expires, cputime_t new_exp)
                cputime_gt(expires, new_exp);
 }
 
-static inline int expires_le(cputime_t expires, cputime_t new_exp)
-{
-        return !cputime_eq(expires, cputime_zero) &&
-               cputime_le(expires, new_exp);
-}
 /*
  * Insert the timer on the appropriate list before any timers that
  * expire later.  This must be called with the tasklist_lock held
- * for reading, and interrupts disabled.
+ * for reading, interrupts disabled and p->sighand->siglock taken.
  */
-static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
+static void arm_timer(struct k_itimer *timer)
 {
         struct task_struct *p = timer->it.cpu.task;
         struct list_head *head, *listpos;
+        struct task_cputime *cputime_expires;
         struct cpu_timer_list *const nt = &timer->it.cpu;
         struct cpu_timer_list *next;
-        unsigned long i;
 
-        head = (CPUCLOCK_PERTHREAD(timer->it_clock) ?
-                p->cpu_timers : p->signal->cpu_timers);
+        if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
+                head = p->cpu_timers;
+                cputime_expires = &p->cputime_expires;
+        } else {
+                head = p->signal->cpu_timers;
+                cputime_expires = &p->signal->cputime_expires;
+        }
         head += CPUCLOCK_WHICH(timer->it_clock);
 
-        BUG_ON(!irqs_disabled());
-        spin_lock(&p->sighand->siglock);
-
         listpos = head;
-        if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) {
-                list_for_each_entry(next, head, entry) {
-                        if (next->expires.sched > nt->expires.sched)
-                                break;
-                        listpos = &next->entry;
-                }
-        } else {
-                list_for_each_entry(next, head, entry) {
-                        if (cputime_gt(next->expires.cpu, nt->expires.cpu))
-                                break;
-                        listpos = &next->entry;
-                }
+        list_for_each_entry(next, head, entry) {
+                if (cpu_time_before(timer->it_clock, nt->expires, next->expires))
+                        break;
+                listpos = &next->entry;
         }
         list_add(&nt->entry, listpos);
 
         if (listpos == head) {
+                union cpu_time_count *exp = &nt->expires;
+
                 /*
-                 * We are the new earliest-expiring timer.
-                 * If we are a thread timer, there can always
-                 * be a process timer telling us to stop earlier.
+                 * We are the new earliest-expiring POSIX 1.b timer, hence
+                 * need to update expiration cache. Take into account that
+                 * for process timers we share expiration cache with itimers
+                 * and RLIMIT_CPU and for thread timers with RLIMIT_RTTIME.
                  */
 
-                if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
-                        union cpu_time_count *exp = &nt->expires;
-
-                        switch (CPUCLOCK_WHICH(timer->it_clock)) {
-                        default:
-                                BUG();
-                        case CPUCLOCK_PROF:
-                                if (expires_gt(p->cputime_expires.prof_exp,
-                                               exp->cpu))
-                                        p->cputime_expires.prof_exp = exp->cpu;
-                                break;
-                        case CPUCLOCK_VIRT:
-                                if (expires_gt(p->cputime_expires.virt_exp,
-                                               exp->cpu))
-                                        p->cputime_expires.virt_exp = exp->cpu;
-                                break;
-                        case CPUCLOCK_SCHED:
-                                if (p->cputime_expires.sched_exp == 0 ||
-                                    p->cputime_expires.sched_exp > exp->sched)
-                                        p->cputime_expires.sched_exp =
-                                                                exp->sched;
-                                break;
-                        }
-                } else {
-                        struct signal_struct *const sig = p->signal;
-                        union cpu_time_count *exp = &timer->it.cpu.expires;
-
-                        /*
-                         * For a process timer, set the cached expiration time.
-                         */
-                        switch (CPUCLOCK_WHICH(timer->it_clock)) {
-                        default:
-                                BUG();
-                        case CPUCLOCK_VIRT:
-                                if (expires_le(sig->it[CPUCLOCK_VIRT].expires,
-                                               exp->cpu))
-                                        break;
-                                sig->cputime_expires.virt_exp = exp->cpu;
-                                break;
-                        case CPUCLOCK_PROF:
-                                if (expires_le(sig->it[CPUCLOCK_PROF].expires,
-                                               exp->cpu))
-                                        break;
-                                i = sig->rlim[RLIMIT_CPU].rlim_cur;
-                                if (i != RLIM_INFINITY &&
-                                    i <= cputime_to_secs(exp->cpu))
-                                        break;
-                                sig->cputime_expires.prof_exp = exp->cpu;
-                                break;
-                        case CPUCLOCK_SCHED:
-                                sig->cputime_expires.sched_exp = exp->sched;
-                                break;
-                        }
+                switch (CPUCLOCK_WHICH(timer->it_clock)) {
+                case CPUCLOCK_PROF:
+                        if (expires_gt(cputime_expires->prof_exp, exp->cpu))
+                                cputime_expires->prof_exp = exp->cpu;
+                        break;
+                case CPUCLOCK_VIRT:
+                        if (expires_gt(cputime_expires->virt_exp, exp->cpu))
+                                cputime_expires->virt_exp = exp->cpu;
+                        break;
+                case CPUCLOCK_SCHED:
+                        if (cputime_expires->sched_exp == 0 ||
+                            cputime_expires->sched_exp > exp->sched)
+                                cputime_expires->sched_exp = exp->sched;
+                        break;
                 }
         }
-
-        spin_unlock(&p->sighand->siglock);
 }
 
 /*
@@ -660,7 +610,12 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
  */
 static void cpu_timer_fire(struct k_itimer *timer)
 {
-        if (unlikely(timer->sigq == NULL)) {
+        if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) {
+                /*
+                 * User don't want any signal.
+                 */
+                timer->it.cpu.expires.sched = 0;
+        } else if (unlikely(timer->sigq == NULL)) {
                 /*
                  * This a special case for clock_nanosleep,
                  * not a normal timer from sys_timer_create.
@@ -721,7 +676,7 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
                         struct itimerspec *new, struct itimerspec *old)
 {
         struct task_struct *p = timer->it.cpu.task;
-        union cpu_time_count old_expires, new_expires, val;
+        union cpu_time_count old_expires, new_expires, old_incr, val;
         int ret;
 
         if (unlikely(p == NULL)) {
@@ -736,10 +691,10 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
         read_lock(&tasklist_lock);
         /*
          * We need the tasklist_lock to protect against reaping that
-         * clears p->signal.  If p has just been reaped, we can no
+         * clears p->sighand.  If p has just been reaped, we can no
          * longer get any information about it at all.
          */
-        if (unlikely(p->signal == NULL)) {
+        if (unlikely(p->sighand == NULL)) {
                 read_unlock(&tasklist_lock);
                 put_task_struct(p);
                 timer->it.cpu.task = NULL;
@@ -752,6 +707,7 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
         BUG_ON(!irqs_disabled());
 
         ret = 0;
+        old_incr = timer->it.cpu.incr;
         spin_lock(&p->sighand->siglock);
         old_expires = timer->it.cpu.expires;
         if (unlikely(timer->it.cpu.firing)) {
@@ -759,7 +715,6 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
                 ret = TIMER_RETRY;
         } else
                 list_del_init(&timer->it.cpu.entry);
-        spin_unlock(&p->sighand->siglock);
 
         /*
          * We need to sample the current value to convert the new
@@ -813,6 +768,7 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
                  * disable this firing since we are already reporting
                  * it as an overrun (thanks to bump_cpu_timer above).
                  */
+                spin_unlock(&p->sighand->siglock);
                 read_unlock(&tasklist_lock);
                 goto out;
         }
@@ -828,11 +784,11 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
          */
         timer->it.cpu.expires = new_expires;
         if (new_expires.sched != 0 &&
-            (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE &&
             cpu_time_before(timer->it_clock, val, new_expires)) {
-                arm_timer(timer, val);
+                arm_timer(timer);
         }
 
+        spin_unlock(&p->sighand->siglock);
         read_unlock(&tasklist_lock);
 
         /*
@@ -853,7 +809,6 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
         timer->it_overrun = -1;
 
         if (new_expires.sched != 0 &&
-            (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE &&
             !cpu_time_before(timer->it_clock, val, new_expires)) {
                 /*
                  * The designated time already passed, so we notify
@@ -867,7 +822,7 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags,
  out:
         if (old) {
                 sample_to_timespec(timer->it_clock,
-                                   timer->it.cpu.incr, &old->it_interval);
+                                   old_incr, &old->it_interval);
         }
         return ret;
 }
@@ -908,7 +863,7 @@ void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp)
                 clear_dead = p->exit_state;
         } else {
                 read_lock(&tasklist_lock);
-                if (unlikely(p->signal == NULL)) {
+                if (unlikely(p->sighand == NULL)) {
                         /*
                          * The process has been reaped.
                          * We can't even collect a sample any more.
@@ -927,25 +882,6 @@ void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp)
                 read_unlock(&tasklist_lock);
         }
 
-        if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) {
-                if (timer->it.cpu.incr.sched == 0 &&
-                    cpu_time_before(timer->it_clock,
-                                    timer->it.cpu.expires, now)) {
-                        /*
-                         * Do-nothing timer expired and has no reload,
-                         * so it's as if it was never set.
-                         */
-                        timer->it.cpu.expires.sched = 0;
-                        itp->it_value.tv_sec = itp->it_value.tv_nsec = 0;
-                        return;
-                }
-                /*
-                 * Account for any expirations and reloads that should
-                 * have happened.
-                 */
-                bump_cpu_timer(timer, now);
-        }
-
         if (unlikely(clear_dead)) {
                 /*
                  * We've noticed that the thread is dead, but
@@ -1066,16 +1002,9 @@ static void stop_process_timers(struct signal_struct *sig)
         struct thread_group_cputimer *cputimer = &sig->cputimer;
         unsigned long flags;
 
-        if (!cputimer->running)
-                return;
-
         spin_lock_irqsave(&cputimer->lock, flags);
         cputimer->running = 0;
         spin_unlock_irqrestore(&cputimer->lock, flags);
-
-        sig->cputime_expires.prof_exp = cputime_zero;
-        sig->cputime_expires.virt_exp = cputime_zero;
-        sig->cputime_expires.sched_exp = 0;
 }
 
 static u32 onecputick;
@@ -1112,6 +1041,23 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
         }
 }
 
+/**
+ * task_cputime_zero - Check a task_cputime struct for all zero fields.
+ *
+ * @cputime:    The struct to compare.
+ *
+ * Checks @cputime to see if all fields are zero.  Returns true if all fields
+ * are zero, false if any field is nonzero.
+ */
+static inline int task_cputime_zero(const struct task_cputime *cputime)
+{
+        if (cputime_eq(cputime->utime, cputime_zero) &&
+            cputime_eq(cputime->stime, cputime_zero) &&
+            cputime->sum_exec_runtime == 0)
+                return 1;
+        return 0;
+}
+
 /*
  * Check for any per-thread CPU timers that have fired and move them
  * off the tsk->*_timers list onto the firing list.  Per-thread timers
@@ -1129,19 +1075,6 @@ static void check_process_timers(struct task_struct *tsk,
         unsigned long soft;
 
         /*
-         * Don't sample the current process CPU clocks if there are no timers.
-         */
-        if (list_empty(&timers[CPUCLOCK_PROF]) &&
-            cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) &&
-            sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY &&
-            list_empty(&timers[CPUCLOCK_VIRT]) &&
-            cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) &&
-            list_empty(&timers[CPUCLOCK_SCHED])) {
-                stop_process_timers(sig);
-                return;
-        }
-
-        /*
          * Collect the current process totals.
          */
         thread_group_cputimer(tsk, &cputime);
@@ -1230,18 +1163,11 @@ static void check_process_timers(struct task_struct *tsk,
                 }
         }
 
-        if (!cputime_eq(prof_expires, cputime_zero) &&
-            (cputime_eq(sig->cputime_expires.prof_exp, cputime_zero) ||
-             cputime_gt(sig->cputime_expires.prof_exp, prof_expires)))
-                sig->cputime_expires.prof_exp = prof_expires;
-        if (!cputime_eq(virt_expires, cputime_zero) &&
-            (cputime_eq(sig->cputime_expires.virt_exp, cputime_zero) ||
-             cputime_gt(sig->cputime_expires.virt_exp, virt_expires)))
-                sig->cputime_expires.virt_exp = virt_expires;
-        if (sched_expires != 0 &&
-            (sig->cputime_expires.sched_exp == 0 ||
-             sig->cputime_expires.sched_exp > sched_expires))
-                sig->cputime_expires.sched_exp = sched_expires;
+        sig->cputime_expires.prof_exp = prof_expires;
+        sig->cputime_expires.virt_exp = virt_expires;
+        sig->cputime_expires.sched_exp = sched_expires;
+        if (task_cputime_zero(&sig->cputime_expires))
+                stop_process_timers(sig);
 }
 
 /*
@@ -1270,9 +1196,10 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
                         goto out;
                 }
                 read_lock(&tasklist_lock); /* arm_timer needs it.  */
+                spin_lock(&p->sighand->siglock);
         } else {
                 read_lock(&tasklist_lock);
-                if (unlikely(p->signal == NULL)) {
+                if (unlikely(p->sighand == NULL)) {
                         /*
                          * The process has been reaped.
                          * We can't even collect a sample any more.
@@ -1290,6 +1217,7 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
                         clear_dead_task(timer, now);
                         goto out_unlock;
                 }
+                spin_lock(&p->sighand->siglock);
                 cpu_timer_sample_group(timer->it_clock, p, &now);
                 bump_cpu_timer(timer, now);
                 /* Leave the tasklist_lock locked for the call below.  */
@@ -1298,7 +1226,9 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
         /*
          * Now re-arm for the new expiry time.
          */
-        arm_timer(timer, now);
+        BUG_ON(!irqs_disabled());
+        arm_timer(timer);
+        spin_unlock(&p->sighand->siglock);
 
 out_unlock:
         read_unlock(&tasklist_lock);
@@ -1310,23 +1240,6 @@ out:
 }
 
 /**
- * task_cputime_zero - Check a task_cputime struct for all zero fields.
- *
- * @cputime:    The struct to compare.
- *
- * Checks @cputime to see if all fields are zero.  Returns true if all fields
- * are zero, false if any field is nonzero.
- */
-static inline int task_cputime_zero(const struct task_cputime *cputime)
-{
-        if (cputime_eq(cputime->utime, cputime_zero) &&
-            cputime_eq(cputime->stime, cputime_zero) &&
-            cputime->sum_exec_runtime == 0)
-                return 1;
-        return 0;
-}
-
-/**
  * task_cputime_expired - Compare two task_cputime entities.
  *
  * @sample:     The task_cputime structure to be checked for expiration.
@@ -1382,7 +1295,7 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
         }
 
         sig = tsk->signal;
-        if (!task_cputime_zero(&sig->cputime_expires)) {
+        if (sig->cputimer.running) {
                 struct task_cputime group_sample;
 
                 thread_group_cputimer(tsk, &group_sample);
@@ -1390,7 +1303,7 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
                         return 1;
         }
 
-        return sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY;
+        return 0;
 }
 
 /*
@@ -1419,7 +1332,12 @@ void run_posix_cpu_timers(struct task_struct *tsk)
          * put them on the firing list.
          */
         check_thread_timers(tsk, &firing);
-        check_process_timers(tsk, &firing);
+        /*
+         * If there are any active process wide timers (POSIX 1.b, itimers,
+         * RLIMIT_CPU) cputimer must be running.
+         */
+        if (tsk->signal->cputimer.running)
+                check_process_timers(tsk, &firing);
 
         /*
          * We must release these locks before taking any timer's lock.
@@ -1456,21 +1374,23 @@ void run_posix_cpu_timers(struct task_struct *tsk)
 }
 
 /*
- * Set one of the process-wide special case CPU timers.
+ * Set one of the process-wide special case CPU timers or RLIMIT_CPU.
  * The tsk->sighand->siglock must be held by the caller.
- * The *newval argument is relative and we update it to be absolute, *oldval
- * is absolute and we update it to be relative.
  */
 void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
                            cputime_t *newval, cputime_t *oldval)
 {
         union cpu_time_count now;
-        struct list_head *head;
 
         BUG_ON(clock_idx == CPUCLOCK_SCHED);
         cpu_timer_sample_group(clock_idx, tsk, &now);
 
         if (oldval) {
+                /*
+                 * We are setting itimer. The *oldval is absolute and we update
+                 * it to be relative, *newval argument is relative and we update
+                 * it to be absolute.
+                 */
                 if (!cputime_eq(*oldval, cputime_zero)) {
                         if (cputime_le(*oldval, now.cpu)) {
                                 /* Just about to fire. */
@@ -1483,33 +1403,21 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
                 if (cputime_eq(*newval, cputime_zero))
                         return;
                 *newval = cputime_add(*newval, now.cpu);
-
-                /*
-                 * If the RLIMIT_CPU timer will expire before the
-                 * ITIMER_PROF timer, we have nothing else to do.
-                 */
-                if (tsk->signal->rlim[RLIMIT_CPU].rlim_cur
-                    < cputime_to_secs(*newval))
-                        return;
         }
 
         /*
-         * Check whether there are any process timers already set to fire
-         * before this one.  If so, we don't have anything more to do.
+         * Update expiration cache if we are the earliest timer, or eventually
+         * RLIMIT_CPU limit is earlier than prof_exp cpu timer expire.
          */
-        head = &tsk->signal->cpu_timers[clock_idx];
-        if (list_empty(head) ||
-            cputime_ge(list_first_entry(head,
-                                  struct cpu_timer_list, entry)->expires.cpu,
-                       *newval)) {
-                switch (clock_idx) {
-                case CPUCLOCK_PROF:
+        switch (clock_idx) {
+        case CPUCLOCK_PROF:
+                if (expires_gt(tsk->signal->cputime_expires.prof_exp, *newval))
                         tsk->signal->cputime_expires.prof_exp = *newval;
-                        break;
-                case CPUCLOCK_VIRT:
+                break;
+        case CPUCLOCK_VIRT:
+                if (expires_gt(tsk->signal->cputime_expires.virt_exp, *newval))
                         tsk->signal->cputime_expires.virt_exp = *newval;
-                        break;
-                }
+                break;
         }
 }
 
diff --git a/kernel/power/Makefile b/kernel/power/Makefile
index 43191815f874..524e058dcf06 100644
--- a/kernel/power/Makefile
+++ b/kernel/power/Makefile
@@ -8,7 +8,8 @@ obj-$(CONFIG_PM_SLEEP)		+= console.o
 obj-$(CONFIG_FREEZER)           += process.o
 obj-$(CONFIG_SUSPEND)           += suspend.o
 obj-$(CONFIG_PM_TEST_SUSPEND)   += suspend_test.o
-obj-$(CONFIG_HIBERNATION)       += hibernate.o snapshot.o swap.o user.o
+obj-$(CONFIG_HIBERNATION)       += hibernate.o snapshot.o swap.o user.o \
+                                   block_io.o
 obj-$(CONFIG_HIBERNATION_NVS)   += hibernate_nvs.o
 
 obj-$(CONFIG_MAGIC_SYSRQ)       += poweroff.o
diff --git a/kernel/power/block_io.c b/kernel/power/block_io.c
new file mode 100644
index 000000000000..97024fd40cd5
--- /dev/null
+++ b/kernel/power/block_io.c
@@ -0,0 +1,103 @@
+/*
+ * This file provides functions for block I/O operations on swap/file.
+ *
+ * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
+ * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/bio.h>
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+#include <linux/swap.h>
+
+#include "power.h"
+
+/**
+ *      submit - submit BIO request.
+ *      @rw:    READ or WRITE.
+ *      @off    physical offset of page.
+ *      @page:  page we're reading or writing.
+ *      @bio_chain: list of pending biod (for async reading)
+ *
+ *      Straight from the textbook - allocate and initialize the bio.
+ *      If we're reading, make sure the page is marked as dirty.
+ *      Then submit it and, if @bio_chain == NULL, wait.
+ */
+static int submit(int rw, struct block_device *bdev, sector_t sector,
+                struct page *page, struct bio **bio_chain)
+{
+        const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
+        struct bio *bio;
+
+        bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
+        bio->bi_sector = sector;
+        bio->bi_bdev = bdev;
+        bio->bi_end_io = end_swap_bio_read;
+
+        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+                printk(KERN_ERR "PM: Adding page to bio failed at %llu\n",
+                        (unsigned long long)sector);
+                bio_put(bio);
+                return -EFAULT;
+        }
+
+        lock_page(page);
+        bio_get(bio);
+
+        if (bio_chain == NULL) {
+                submit_bio(bio_rw, bio);
+                wait_on_page_locked(page);
+                if (rw == READ)
+                        bio_set_pages_dirty(bio);
+                bio_put(bio);
+        } else {
+                if (rw == READ)
+                        get_page(page); /* These pages are freed later */
+                bio->bi_private = *bio_chain;
+                *bio_chain = bio;
+                submit_bio(bio_rw, bio);
+        }
+        return 0;
+}
+
+int hib_bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
+{
+        return submit(READ, hib_resume_bdev, page_off * (PAGE_SIZE >> 9),
+                        virt_to_page(addr), bio_chain);
+}
+
+int hib_bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
+{
+        return submit(WRITE, hib_resume_bdev, page_off * (PAGE_SIZE >> 9),
+                        virt_to_page(addr), bio_chain);
+}
+
+int hib_wait_on_bio_chain(struct bio **bio_chain)
+{
+        struct bio *bio;
+        struct bio *next_bio;
+        int ret = 0;
+
+        if (bio_chain == NULL)
+                return 0;
+
+        bio = *bio_chain;
+        if (bio == NULL)
+                return 0;
+        while (bio) {
+                struct page *page;
+
+                next_bio = bio->bi_private;
+                page = bio->bi_io_vec[0].bv_page;
+                wait_on_page_locked(page);
+                if (!PageUptodate(page) || PageError(page))
+                        ret = -EIO;
+                put_page(page);
+                bio_put(bio);
+                bio = next_bio;
+        }
+        *bio_chain = NULL;
+        return ret;
+}
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 46c5a26630a3..006270fe382d 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -97,24 +97,12 @@ extern int hibernate_preallocate_memory(void);
  */
 
 struct snapshot_handle {
-        loff_t          offset; /* number of the last byte ready for reading
-                                 * or writing in the sequence
-                                 */
         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
                                  * next operation will refer to (ie. current)
                                  */
-        unsigned int    cur_offset;     /* offset with respect to the current
-                                         * block (for the next operation)
-                                         */
-        unsigned int    prev;   /* number of the block of PAGE_SIZE bytes that
-                                 * was the current one previously
-                                 */
         void            *buffer;        /* address of the block to read from
                                          * or write to
                                          */
-        unsigned int    buf_offset;     /* location to read from or write to,
-                                         * given as a displacement from 'buffer'
-                                         */
         int             sync_read;      /* Set to one to notify the caller of
                                          * snapshot_write_next() that it may
                                          * need to call wait_on_bio_chain()
@@ -125,12 +113,12 @@ struct snapshot_handle {
  * snapshot_read_next()/snapshot_write_next() is allowed to
  * read/write data after the function returns
  */
-#define data_of(handle) ((handle).buffer + (handle).buf_offset)
+#define data_of(handle) ((handle).buffer)
 
 extern unsigned int snapshot_additional_pages(struct zone *zone);
 extern unsigned long snapshot_get_image_size(void);
-extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
-extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
+extern int snapshot_read_next(struct snapshot_handle *handle);
+extern int snapshot_write_next(struct snapshot_handle *handle);
 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 
@@ -154,6 +142,15 @@ extern int swsusp_read(unsigned int *flags_p);
 extern int swsusp_write(unsigned int flags);
 extern void swsusp_close(fmode_t);
 
+/* kernel/power/block_io.c */
+extern struct block_device *hib_resume_bdev;
+
+extern int hib_bio_read_page(pgoff_t page_off, void *addr,
+                struct bio **bio_chain);
+extern int hib_bio_write_page(pgoff_t page_off, void *addr,
+                struct bio **bio_chain);
+extern int hib_wait_on_bio_chain(struct bio **bio_chain);
+
 struct timeval;
 /* kernel/power/swsusp.c */
 extern void swsusp_show_speed(struct timeval *, struct timeval *,
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index be861c26dda7..25ce010e9f8b 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1604,14 +1604,9 @@ pack_pfns(unsigned long *buf, struct memory_bitmap *bm)
  *      snapshot_handle structure.  The structure gets updated and a pointer
  *      to it should be passed to this function every next time.
  *
- *      The @count parameter should contain the number of bytes the caller
- *      wants to read from the snapshot.  It must not be zero.
- *
  *      On success the function returns a positive number.  Then, the caller
  *      is allowed to read up to the returned number of bytes from the memory
- *      location computed by the data_of() macro.  The number returned
- *      may be smaller than @count, but this only happens if the read would
- *      cross a page boundary otherwise.
+ *      location computed by the data_of() macro.
  *
  *      The function returns 0 to indicate the end of data stream condition,
  *      and a negative number is returned on error.  In such cases the
@@ -1619,7 +1614,7 @@ pack_pfns(unsigned long *buf, struct memory_bitmap *bm)
  *      any more.
  */
 
-int snapshot_read_next(struct snapshot_handle *handle, size_t count)
+int snapshot_read_next(struct snapshot_handle *handle)
 {
         if (handle->cur > nr_meta_pages + nr_copy_pages)
                 return 0;
@@ -1630,7 +1625,7 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
                 if (!buffer)
                         return -ENOMEM;
         }
-        if (!handle->offset) {
+        if (!handle->cur) {
                 int error;
 
                 error = init_header((struct swsusp_info *)buffer);
@@ -1639,42 +1634,30 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
                 handle->buffer = buffer;
                 memory_bm_position_reset(&orig_bm);
                 memory_bm_position_reset(&copy_bm);
-        }
-        if (handle->prev < handle->cur) {
-                if (handle->cur <= nr_meta_pages) {
-                        memset(buffer, 0, PAGE_SIZE);
-                        pack_pfns(buffer, &orig_bm);
-                } else {
-                        struct page *page;
+        } else if (handle->cur <= nr_meta_pages) {
+                memset(buffer, 0, PAGE_SIZE);
+                pack_pfns(buffer, &orig_bm);
+        } else {
+                struct page *page;
 
-                        page = pfn_to_page(memory_bm_next_pfn(&copy_bm));
-                        if (PageHighMem(page)) {
-                                /* Highmem pages are copied to the buffer,
-                                 * because we can't return with a kmapped
-                                 * highmem page (we may not be called again).
-                                 */
-                                void *kaddr;
+                page = pfn_to_page(memory_bm_next_pfn(&copy_bm));
+                if (PageHighMem(page)) {
+                        /* Highmem pages are copied to the buffer,
+                         * because we can't return with a kmapped
+                         * highmem page (we may not be called again).
+                         */
+                        void *kaddr;
 
-                                kaddr = kmap_atomic(page, KM_USER0);
-                                memcpy(buffer, kaddr, PAGE_SIZE);
-                                kunmap_atomic(kaddr, KM_USER0);
-                                handle->buffer = buffer;
-                        } else {
-                                handle->buffer = page_address(page);
-                        }
+                        kaddr = kmap_atomic(page, KM_USER0);
+                        memcpy(buffer, kaddr, PAGE_SIZE);
+                        kunmap_atomic(kaddr, KM_USER0);
+                        handle->buffer = buffer;
+                } else {
+                        handle->buffer = page_address(page);
                 }
-                handle->prev = handle->cur;
-        }
-        handle->buf_offset = handle->cur_offset;
-        if (handle->cur_offset + count >= PAGE_SIZE) {
-                count = PAGE_SIZE - handle->cur_offset;
-                handle->cur_offset = 0;
-                handle->cur++;
-        } else {
-                handle->cur_offset += count;
         }
-        handle->offset += count;
-        return count;
+        handle->cur++;
+        return PAGE_SIZE;
 }
 
 /**
@@ -2133,14 +2116,9 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
  *      snapshot_handle structure.  The structure gets updated and a pointer
  *      to it should be passed to this function every next time.
  *
- *      The @count parameter should contain the number of bytes the caller
- *      wants to write to the image.  It must not be zero.
- *
  *      On success the function returns a positive number.  Then, the caller
  *      is allowed to write up to the returned number of bytes to the memory
- *      location computed by the data_of() macro.  The number returned
- *      may be smaller than @count, but this only happens if the write would
- *      cross a page boundary otherwise.
+ *      location computed by the data_of() macro.
  *
  *      The function returns 0 to indicate the "end of file" condition,
  *      and a negative number is returned on error.  In such cases the
@@ -2148,16 +2126,18 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
  *      any more.
  */
 
-int snapshot_write_next(struct snapshot_handle *handle, size_t count)
+int snapshot_write_next(struct snapshot_handle *handle)
 {
         static struct chain_allocator ca;
         int error = 0;
 
         /* Check if we have already loaded the entire image */
-        if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages)
+        if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages)
                 return 0;
 
-        if (handle->offset == 0) {
+        handle->sync_read = 1;
+
+        if (!handle->cur) {
                 if (!buffer)
                         /* This makes the buffer be freed by swsusp_free() */
                         buffer = get_image_page(GFP_ATOMIC, PG_ANY);
@@ -2166,56 +2146,43 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
                         return -ENOMEM;
 
                 handle->buffer = buffer;
-        }
-        handle->sync_read = 1;
-        if (handle->prev < handle->cur) {
-                if (handle->prev == 0) {
-                        error = load_header(buffer);
-                        if (error)
-                                return error;
+        } else if (handle->cur == 1) {
+                error = load_header(buffer);
+                if (error)
+                        return error;
 
-                        error = memory_bm_create(&copy_bm, GFP_ATOMIC, PG_ANY);
-                        if (error)
-                                return error;
+                error = memory_bm_create(&copy_bm, GFP_ATOMIC, PG_ANY);
+                if (error)
+                        return error;
+
+        } else if (handle->cur <= nr_meta_pages + 1) {
+                error = unpack_orig_pfns(buffer, &copy_bm);
+                if (error)
+                        return error;
 
-                } else if (handle->prev <= nr_meta_pages) {
-                        error = unpack_orig_pfns(buffer, &copy_bm);
+                if (handle->cur == nr_meta_pages + 1) {
+                        error = prepare_image(&orig_bm, &copy_bm);
                         if (error)
                                 return error;
 
-                        if (handle->prev == nr_meta_pages) {
-                                error = prepare_image(&orig_bm, &copy_bm);
-                                if (error)
-                                        return error;
-
-                                chain_init(&ca, GFP_ATOMIC, PG_SAFE);
-                                memory_bm_position_reset(&orig_bm);
-                                restore_pblist = NULL;
-                                handle->buffer = get_buffer(&orig_bm, &ca);
-                                handle->sync_read = 0;
-                                if (IS_ERR(handle->buffer))
-                                        return PTR_ERR(handle->buffer);
-                        }
-                } else {
-                        copy_last_highmem_page();
+                        chain_init(&ca, GFP_ATOMIC, PG_SAFE);
+                        memory_bm_position_reset(&orig_bm);
+                        restore_pblist = NULL;
                         handle->buffer = get_buffer(&orig_bm, &ca);
+                        handle->sync_read = 0;
                         if (IS_ERR(handle->buffer))
                                 return PTR_ERR(handle->buffer);
-                        if (handle->buffer != buffer)
-                                handle->sync_read = 0;
                 }
-                handle->prev = handle->cur;
-        }
-        handle->buf_offset = handle->cur_offset;
-        if (handle->cur_offset + count >= PAGE_SIZE) {
-                count = PAGE_SIZE - handle->cur_offset;
-                handle->cur_offset = 0;
-                handle->cur++;
         } else {
-                handle->cur_offset += count;
+                copy_last_highmem_page();
+                handle->buffer = get_buffer(&orig_bm, &ca);
+                if (IS_ERR(handle->buffer))
+                        return PTR_ERR(handle->buffer);
+                if (handle->buffer != buffer)
+                        handle->sync_read = 0;
         }
-        handle->offset += count;
-        return count;
+        handle->cur++;
+        return PAGE_SIZE;
 }
 
 /**
@@ -2230,7 +2197,7 @@ void snapshot_write_finalize(struct snapshot_handle *handle)
 {
         copy_last_highmem_page();
         /* Free only if we have loaded the image entirely */
-        if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) {
+        if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages) {
                 memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR);
                 free_highmem_data();
         }
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 66824d71983a..b0bb21778391 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -29,6 +29,40 @@
 
 #define SWSUSP_SIG      "S1SUSPEND"
 
+/*
+ *      The swap map is a data structure used for keeping track of each page
+ *      written to a swap partition.  It consists of many swap_map_page
+ *      structures that contain each an array of MAP_PAGE_SIZE swap entries.
+ *      These structures are stored on the swap and linked together with the
+ *      help of the .next_swap member.
+ *
+ *      The swap map is created during suspend.  The swap map pages are
+ *      allocated and populated one at a time, so we only need one memory
+ *      page to set up the entire structure.
+ *
+ *      During resume we also only need to use one swap_map_page structure
+ *      at a time.
+ */
+
+#define MAP_PAGE_ENTRIES        (PAGE_SIZE / sizeof(sector_t) - 1)
+
+struct swap_map_page {
+        sector_t entries[MAP_PAGE_ENTRIES];
+        sector_t next_swap;
+};
+
+/**
+ *      The swap_map_handle structure is used for handling swap in
+ *      a file-alike way
+ */
+
+struct swap_map_handle {
+        struct swap_map_page *cur;
+        sector_t cur_swap;
+        sector_t first_sector;
+        unsigned int k;
+};
+
 struct swsusp_header {
         char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int)];
         sector_t image;
@@ -145,110 +179,24 @@ int swsusp_swap_in_use(void)
  */
 
 static unsigned short root_swap = 0xffff;
-static struct block_device *resume_bdev;
-
-/**
- *      submit - submit BIO request.
- *      @rw:    READ or WRITE.
- *      @off    physical offset of page.
- *      @page:  page we're reading or writing.
- *      @bio_chain: list of pending biod (for async reading)
- *
- *      Straight from the textbook - allocate and initialize the bio.
- *      If we're reading, make sure the page is marked as dirty.
- *      Then submit it and, if @bio_chain == NULL, wait.
- */
-static int submit(int rw, pgoff_t page_off, struct page *page,
-                        struct bio **bio_chain)
-{
-        const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
-        struct bio *bio;
-
-        bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
-        bio->bi_sector = page_off * (PAGE_SIZE >> 9);
-        bio->bi_bdev = resume_bdev;
-        bio->bi_end_io = end_swap_bio_read;
-
-        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
-                printk(KERN_ERR "PM: Adding page to bio failed at %ld\n",
-                        page_off);
-                bio_put(bio);
-                return -EFAULT;
-        }
-
-        lock_page(page);
-        bio_get(bio);
-
-        if (bio_chain == NULL) {
-                submit_bio(bio_rw, bio);
-                wait_on_page_locked(page);
-                if (rw == READ)
-                        bio_set_pages_dirty(bio);
-                bio_put(bio);
-        } else {
-                if (rw == READ)
-                        get_page(page); /* These pages are freed later */
-                bio->bi_private = *bio_chain;
-                *bio_chain = bio;
-                submit_bio(bio_rw, bio);
-        }
-        return 0;
-}
-
-static int bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
-        return submit(READ, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
-        return submit(WRITE, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int wait_on_bio_chain(struct bio **bio_chain)
-{
-        struct bio *bio;
-        struct bio *next_bio;
-        int ret = 0;
-
-        if (bio_chain == NULL)
-                return 0;
-
-        bio = *bio_chain;
-        if (bio == NULL)
-                return 0;
-        while (bio) {
-                struct page *page;
-
-                next_bio = bio->bi_private;
-                page = bio->bi_io_vec[0].bv_page;
-                wait_on_page_locked(page);
-                if (!PageUptodate(page) || PageError(page))
-                        ret = -EIO;
-                put_page(page);
-                bio_put(bio);
-                bio = next_bio;
-        }
-        *bio_chain = NULL;
-        return ret;
-}
+struct block_device *hib_resume_bdev;
 
 /*
  * Saving part
  */
 
-static int mark_swapfiles(sector_t start, unsigned int flags)
+static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
 {
         int error;
 
-        bio_read_page(swsusp_resume_block, swsusp_header, NULL);
+        hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL);
         if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
             !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
                 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
                 memcpy(swsusp_header->sig,SWSUSP_SIG, 10);
-                swsusp_header->image = start;
+                swsusp_header->image = handle->first_sector;
                 swsusp_header->flags = flags;
-                error = bio_write_page(swsusp_resume_block,
+                error = hib_bio_write_page(swsusp_resume_block,
                                         swsusp_header, NULL);
         } else {
                 printk(KERN_ERR "PM: Swap header not found!\n");
@@ -260,25 +208,26 @@ static int mark_swapfiles(sector_t start, unsigned int flags)
 /**
  *      swsusp_swap_check - check if the resume device is a swap device
  *      and get its index (if so)
+ *
+ *      This is called before saving image
  */
-
-static int swsusp_swap_check(void) /* This is called before saving image */
+static int swsusp_swap_check(void)
 {
         int res;
 
         res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
-                        &resume_bdev);
+                        &hib_resume_bdev);
         if (res < 0)
                 return res;
 
         root_swap = res;
-        res = blkdev_get(resume_bdev, FMODE_WRITE);
+        res = blkdev_get(hib_resume_bdev, FMODE_WRITE);
         if (res)
                 return res;
 
-        res = set_blocksize(resume_bdev, PAGE_SIZE);
+        res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
         if (res < 0)
-                blkdev_put(resume_bdev, FMODE_WRITE);
+                blkdev_put(hib_resume_bdev, FMODE_WRITE);
 
         return res;
 }
@@ -309,42 +258,9 @@ static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
         } else {
                 src = buf;
         }
-        return bio_write_page(offset, src, bio_chain);
+        return hib_bio_write_page(offset, src, bio_chain);
 }
 
-/*
- *      The swap map is a data structure used for keeping track of each page
- *      written to a swap partition.  It consists of many swap_map_page
- *      structures that contain each an array of MAP_PAGE_SIZE swap entries.
- *      These structures are stored on the swap and linked together with the
- *      help of the .next_swap member.
- *
- *      The swap map is created during suspend.  The swap map pages are
- *      allocated and populated one at a time, so we only need one memory
- *      page to set up the entire structure.
- *
- *      During resume we also only need to use one swap_map_page structure
- *      at a time.
- */
-
-#define MAP_PAGE_ENTRIES        (PAGE_SIZE / sizeof(sector_t) - 1)
-
-struct swap_map_page {
-        sector_t entries[MAP_PAGE_ENTRIES];
-        sector_t next_swap;
-};
-
-/**
- *      The swap_map_handle structure is used for handling swap in
- *      a file-alike way
- */
-
-struct swap_map_handle {
-        struct swap_map_page *cur;
-        sector_t cur_swap;
-        unsigned int k;
-};
-
 static void release_swap_writer(struct swap_map_handle *handle)
 {
         if (handle->cur)
@@ -354,16 +270,33 @@ static void release_swap_writer(struct swap_map_handle *handle)
 
 static int get_swap_writer(struct swap_map_handle *handle)
 {
+        int ret;
+
+        ret = swsusp_swap_check();
+        if (ret) {
+                if (ret != -ENOSPC)
+                        printk(KERN_ERR "PM: Cannot find swap device, try "
+                                        "swapon -a.\n");
+                return ret;
+        }
         handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
-        if (!handle->cur)
-                return -ENOMEM;
+        if (!handle->cur) {
+                ret = -ENOMEM;
+                goto err_close;
+        }
         handle->cur_swap = alloc_swapdev_block(root_swap);
         if (!handle->cur_swap) {
-                release_swap_writer(handle);
-                return -ENOSPC;
+                ret = -ENOSPC;
+                goto err_rel;
         }
         handle->k = 0;
+        handle->first_sector = handle->cur_swap;
         return 0;
+err_rel:
+        release_swap_writer(handle);
+err_close:
+        swsusp_close(FMODE_WRITE);
+        return ret;
 }
 
 static int swap_write_page(struct swap_map_handle *handle, void *buf,
@@ -380,7 +313,7 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
                 return error;
         handle->cur->entries[handle->k++] = offset;
         if (handle->k >= MAP_PAGE_ENTRIES) {
-                error = wait_on_bio_chain(bio_chain);
+                error = hib_wait_on_bio_chain(bio_chain);
                 if (error)
                         goto out;
                 offset = alloc_swapdev_block(root_swap);
@@ -406,6 +339,24 @@ static int flush_swap_writer(struct swap_map_handle *handle)
                 return -EINVAL;
 }
 
+static int swap_writer_finish(struct swap_map_handle *handle,
+                unsigned int flags, int error)
+{
+        if (!error) {
+                flush_swap_writer(handle);
+                printk(KERN_INFO "PM: S");
+                error = mark_swapfiles(handle, flags);
+                printk("|\n");
+        }
+
+        if (error)
+                free_all_swap_pages(root_swap);
+        release_swap_writer(handle);
+        swsusp_close(FMODE_WRITE);
+
+        return error;
+}
+
 /**
  *      save_image - save the suspend image data
  */
@@ -431,7 +382,7 @@ static int save_image(struct swap_map_handle *handle,
         bio = NULL;
         do_gettimeofday(&start);
         while (1) {
-                ret = snapshot_read_next(snapshot, PAGE_SIZE);
+                ret = snapshot_read_next(snapshot);
                 if (ret <= 0)
                         break;
                 ret = swap_write_page(handle, data_of(*snapshot), &bio);
@@ -441,7 +392,7 @@ static int save_image(struct swap_map_handle *handle,
                         printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
                 nr_pages++;
         }
-        err2 = wait_on_bio_chain(&bio);
+        err2 = hib_wait_on_bio_chain(&bio);
         do_gettimeofday(&stop);
         if (!ret)
                 ret = err2;
@@ -483,50 +434,34 @@ int swsusp_write(unsigned int flags)
         struct swap_map_handle handle;
         struct snapshot_handle snapshot;
         struct swsusp_info *header;
+        unsigned long pages;
         int error;
 
-        error = swsusp_swap_check();
+        pages = snapshot_get_image_size();
+        error = get_swap_writer(&handle);
         if (error) {
-                printk(KERN_ERR "PM: Cannot find swap device, try "
-                                "swapon -a.\n");
+                printk(KERN_ERR "PM: Cannot get swap writer\n");
                 return error;
         }
+        if (!enough_swap(pages)) {
+                printk(KERN_ERR "PM: Not enough free swap\n");
+                error = -ENOSPC;
+                goto out_finish;
+        }
         memset(&snapshot, 0, sizeof(struct snapshot_handle));
-        error = snapshot_read_next(&snapshot, PAGE_SIZE);
+        error = snapshot_read_next(&snapshot);
         if (error < PAGE_SIZE) {
                 if (error >= 0)
                         error = -EFAULT;
 
-                goto out;
+                goto out_finish;
         }
         header = (struct swsusp_info *)data_of(snapshot);
-        if (!enough_swap(header->pages)) {
-                printk(KERN_ERR "PM: Not enough free swap\n");
-                error = -ENOSPC;
-                goto out;
-        }
-        error = get_swap_writer(&handle);
-        if (!error) {
-                sector_t start = handle.cur_swap;
-
-                error = swap_write_page(&handle, header, NULL);
-                if (!error)
-                        error = save_image(&handle, &snapshot,
-                                        header->pages - 1);
-
-                if (!error) {
-                        flush_swap_writer(&handle);
-                        printk(KERN_INFO "PM: S");
-                        error = mark_swapfiles(start, flags);
-                        printk("|\n");
-                }
-        }
-        if (error)
-                free_all_swap_pages(root_swap);
-
-        release_swap_writer(&handle);
- out:
-        swsusp_close(FMODE_WRITE);
+        error = swap_write_page(&handle, header, NULL);
+        if (!error)
+                error = save_image(&handle, &snapshot, pages - 1);
+out_finish:
+        error = swap_writer_finish(&handle, flags, error);
         return error;
 }
 
@@ -542,18 +477,21 @@ static void release_swap_reader(struct swap_map_handle *handle)
         handle->cur = NULL;
 }
 
-static int get_swap_reader(struct swap_map_handle *handle, sector_t start)
+static int get_swap_reader(struct swap_map_handle *handle,
+                unsigned int *flags_p)
 {
         int error;
 
-        if (!start)
+        *flags_p = swsusp_header->flags;
+
+        if (!swsusp_header->image) /* how can this happen? */
                 return -EINVAL;
 
         handle->cur = (struct swap_map_page *)get_zeroed_page(__GFP_WAIT | __GFP_HIGH);
         if (!handle->cur)
                 return -ENOMEM;
 
-        error = bio_read_page(start, handle->cur, NULL);
+        error = hib_bio_read_page(swsusp_header->image, handle->cur, NULL);
         if (error) {
                 release_swap_reader(handle);
                 return error;
@@ -573,21 +511,28 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf,
         offset = handle->cur->entries[handle->k];
         if (!offset)
                 return -EFAULT;
-        error = bio_read_page(offset, buf, bio_chain);
+        error = hib_bio_read_page(offset, buf, bio_chain);
         if (error)
                 return error;
         if (++handle->k >= MAP_PAGE_ENTRIES) {
-                error = wait_on_bio_chain(bio_chain);
+                error = hib_wait_on_bio_chain(bio_chain);
                 handle->k = 0;
                 offset = handle->cur->next_swap;
                 if (!offset)
                         release_swap_reader(handle);
                 else if (!error)
-                        error = bio_read_page(offset, handle->cur, NULL);
+                        error = hib_bio_read_page(offset, handle->cur, NULL);
         }
         return error;
 }
 
+static int swap_reader_finish(struct swap_map_handle *handle)
+{
+        release_swap_reader(handle);
+
+        return 0;
+}
+
 /**
  *      load_image - load the image using the swap map handle
  *      @handle and the snapshot handle @snapshot
@@ -615,21 +560,21 @@ static int load_image(struct swap_map_handle *handle,
         bio = NULL;
         do_gettimeofday(&start);
         for ( ; ; ) {
-                error = snapshot_write_next(snapshot, PAGE_SIZE);
+                error = snapshot_write_next(snapshot);
                 if (error <= 0)
                         break;
                 error = swap_read_page(handle, data_of(*snapshot), &bio);
                 if (error)
                         break;
                 if (snapshot->sync_read)
-                        error = wait_on_bio_chain(&bio);
+                        error = hib_wait_on_bio_chain(&bio);
                 if (error)
                         break;
                 if (!(nr_pages % m))
                         printk("\b\b\b\b%3d%%", nr_pages / m);
                 nr_pages++;
         }
-        err2 = wait_on_bio_chain(&bio);
+        err2 = hib_wait_on_bio_chain(&bio);
         do_gettimeofday(&stop);
         if (!error)
                 error = err2;
@@ -657,20 +602,20 @@ int swsusp_read(unsigned int *flags_p)
         struct snapshot_handle snapshot;
         struct swsusp_info *header;
 
-        *flags_p = swsusp_header->flags;
-
         memset(&snapshot, 0, sizeof(struct snapshot_handle));
-        error = snapshot_write_next(&snapshot, PAGE_SIZE);
+        error = snapshot_write_next(&snapshot);
         if (error < PAGE_SIZE)
                 return error < 0 ? error : -EFAULT;
         header = (struct swsusp_info *)data_of(snapshot);
-        error = get_swap_reader(&handle, swsusp_header->image);
+        error = get_swap_reader(&handle, flags_p);
+        if (error)
+                goto end;
         if (!error)
                 error = swap_read_page(&handle, header, NULL);
         if (!error)
                 error = load_image(&handle, &snapshot, header->pages - 1);
-        release_swap_reader(&handle);
-
+        swap_reader_finish(&handle);
+end:
         if (!error)
                 pr_debug("PM: Image successfully loaded\n");
         else
@@ -686,11 +631,11 @@ int swsusp_check(void)
 {
         int error;
 
-        resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
-        if (!IS_ERR(resume_bdev)) {
-                set_blocksize(resume_bdev, PAGE_SIZE);
+        hib_resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
+        if (!IS_ERR(hib_resume_bdev)) {
+                set_blocksize(hib_resume_bdev, PAGE_SIZE);
                 memset(swsusp_header, 0, PAGE_SIZE);
-                error = bio_read_page(swsusp_resume_block,
+                error = hib_bio_read_page(swsusp_resume_block,
                                         swsusp_header, NULL);
                 if (error)
                         goto put;
@@ -698,7 +643,7 @@ int swsusp_check(void)
                 if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {
                         memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
                         /* Reset swap signature now */
-                        error = bio_write_page(swsusp_resume_block,
+                        error = hib_bio_write_page(swsusp_resume_block,
                                                 swsusp_header, NULL);
                 } else {
                         error = -EINVAL;
@@ -706,11 +651,11 @@ int swsusp_check(void)
 
 put:
                 if (error)
-                        blkdev_put(resume_bdev, FMODE_READ);
+                        blkdev_put(hib_resume_bdev, FMODE_READ);
                 else
                         pr_debug("PM: Signature found, resuming\n");
         } else {
-                error = PTR_ERR(resume_bdev);
+                error = PTR_ERR(hib_resume_bdev);
         }
 
         if (error)
@@ -725,12 +670,12 @@ put:
 
 void swsusp_close(fmode_t mode)
 {
-        if (IS_ERR(resume_bdev)) {
+        if (IS_ERR(hib_resume_bdev)) {
                 pr_debug("PM: Image device not initialised\n");
                 return;
         }
 
-        blkdev_put(resume_bdev, mode);
+        blkdev_put(hib_resume_bdev, mode);
 }
 
 static int swsusp_header_init(void)
diff --git a/kernel/power/user.c b/kernel/power/user.c
index a8c96212bc1b..e819e17877ca 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -151,6 +151,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
 {
         struct snapshot_data *data;
         ssize_t res;
+        loff_t pg_offp = *offp & ~PAGE_MASK;
 
         mutex_lock(&pm_mutex);
 
@@ -159,14 +160,19 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
                 res = -ENODATA;
                 goto Unlock;
         }
-        res = snapshot_read_next(&data->handle, count);
-        if (res > 0) {
-                if (copy_to_user(buf, data_of(data->handle), res))
-                        res = -EFAULT;
-                else
-                        *offp = data->handle.offset;
+        if (!pg_offp) { /* on page boundary? */
+                res = snapshot_read_next(&data->handle);
+                if (res <= 0)
+                        goto Unlock;
+        } else {
+                res = PAGE_SIZE - pg_offp;
         }
 
+        res = simple_read_from_buffer(buf, count, &pg_offp,
+                        data_of(data->handle), res);
+        if (res > 0)
+                *offp += res;
+
  Unlock:
         mutex_unlock(&pm_mutex);
 
@@ -178,18 +184,25 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
 {
         struct snapshot_data *data;
         ssize_t res;
+        loff_t pg_offp = *offp & ~PAGE_MASK;
 
         mutex_lock(&pm_mutex);
 
         data = filp->private_data;
-        res = snapshot_write_next(&data->handle, count);
-        if (res > 0) {
-                if (copy_from_user(data_of(data->handle), buf, res))
-                        res = -EFAULT;
-                else
-                        *offp = data->handle.offset;
+
+        if (!pg_offp) {
+                res = snapshot_write_next(&data->handle);
+                if (res <= 0)
+                        goto unlock;
+        } else {
+                res = PAGE_SIZE - pg_offp;
         }
 
+        res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp,
+                        buf, count);
+        if (res > 0)
+                *offp += res;
+unlock:
         mutex_unlock(&pm_mutex);
 
         return res;
diff --git a/kernel/printk.c b/kernel/printk.c
index 75077ad0b537..444b770c9595 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -33,6 +33,7 @@
 #include <linux/bootmem.h>
 #include <linux/syscalls.h>
 #include <linux/kexec.h>
+#include <linux/kdb.h>
 #include <linux/ratelimit.h>
 #include <linux/kmsg_dump.h>
 #include <linux/syslog.h>
@@ -413,6 +414,22 @@ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
         return do_syslog(type, buf, len, SYSLOG_FROM_CALL);
 }
 
+#ifdef  CONFIG_KGDB_KDB
+/* kdb dmesg command needs access to the syslog buffer.  do_syslog()
+ * uses locks so it cannot be used during debugging.  Just tell kdb
+ * where the start and end of the physical and logical logs are.  This
+ * is equivalent to do_syslog(3).
+ */
+void kdb_syslog_data(char *syslog_data[4])
+{
+        syslog_data[0] = log_buf;
+        syslog_data[1] = log_buf + log_buf_len;
+        syslog_data[2] = log_buf + log_end -
+                (logged_chars < log_buf_len ? logged_chars : log_buf_len);
+        syslog_data[3] = log_buf + log_end;
+}
+#endif  /* CONFIG_KGDB_KDB */
+
 /*
  * Call the console drivers on a range of log_buf
  */
@@ -586,6 +603,14 @@ asmlinkage int printk(const char *fmt, ...)
         va_list args;
         int r;
 
+#ifdef CONFIG_KGDB_KDB
+        if (unlikely(kdb_trap_printk)) {
+                va_start(args, fmt);
+                r = vkdb_printf(fmt, args);
+                va_end(args);
+                return r;
+        }
+#endif
         va_start(args, fmt);
         r = vprintk(fmt, args);
         va_end(args);
diff --git a/kernel/profile.c b/kernel/profile.c
index dfadc5b729f1..b22a899934cc 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -365,14 +365,14 @@ static int __cpuinit profile_cpu_callback(struct notifier_block *info,
         switch (action) {
         case CPU_UP_PREPARE:
         case CPU_UP_PREPARE_FROZEN:
-                node = cpu_to_node(cpu);
+                node = cpu_to_mem(cpu);
                 per_cpu(cpu_profile_flip, cpu) = 0;
                 if (!per_cpu(cpu_profile_hits, cpu)[1]) {
                         page = alloc_pages_exact_node(node,
                                         GFP_KERNEL | __GFP_ZERO,
                                         0);
                         if (!page)
-                                return NOTIFY_BAD;
+                                return notifier_from_errno(-ENOMEM);
                         per_cpu(cpu_profile_hits, cpu)[1] = page_address(page);
                 }
                 if (!per_cpu(cpu_profile_hits, cpu)[0]) {
@@ -388,7 +388,7 @@ out_free:
                 page = virt_to_page(per_cpu(cpu_profile_hits, cpu)[1]);
                 per_cpu(cpu_profile_hits, cpu)[1] = NULL;
                 __free_page(page);
-                return NOTIFY_BAD;
+                return notifier_from_errno(-ENOMEM);
         case CPU_ONLINE:
         case CPU_ONLINE_FROZEN:
                 if (prof_cpu_mask != NULL)
@@ -567,7 +567,7 @@ static int create_hash_tables(void)
         int cpu;
 
         for_each_online_cpu(cpu) {
-                int node = cpu_to_node(cpu);
+                int node = cpu_to_mem(cpu);
                 struct page *page;
 
                 page = alloc_pages_exact_node(node,
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 42ad8ae729a0..74a3d693c196 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -14,7 +14,6 @@
 #include <linux/mm.h>
 #include <linux/highmem.h>
 #include <linux/pagemap.h>
-#include <linux/smp_lock.h>
 #include <linux/ptrace.h>
 #include <linux/security.h>
 #include <linux/signal.h>
@@ -76,7 +75,6 @@ void __ptrace_unlink(struct task_struct *child)
         child->parent = child->real_parent;
         list_del_init(&child->ptrace_entry);
 
-        arch_ptrace_untrace(child);
         if (task_is_traced(child))
                 ptrace_untrace(child);
 }
@@ -596,6 +594,32 @@ int ptrace_request(struct task_struct *child, long request,
                 ret = ptrace_detach(child, data);
                 break;
 
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+        case PTRACE_GETFDPIC: {
+                struct mm_struct *mm = get_task_mm(child);
+                unsigned long tmp = 0;
+
+                ret = -ESRCH;
+                if (!mm)
+                        break;
+
+                switch (addr) {
+                case PTRACE_GETFDPIC_EXEC:
+                        tmp = mm->context.exec_fdpic_loadmap;
+                        break;
+                case PTRACE_GETFDPIC_INTERP:
+                        tmp = mm->context.interp_fdpic_loadmap;
+                        break;
+                default:
+                        break;
+                }
+                mmput(mm);
+
+                ret = put_user(tmp, (unsigned long __user *) data);
+                break;
+        }
+#endif
+
 #ifdef PTRACE_SINGLESTEP
         case PTRACE_SINGLESTEP:
 #endif
@@ -666,10 +690,6 @@ SYSCALL_DEFINE4(ptrace, long, request, long, pid, long, addr, long, data)
         struct task_struct *child;
         long ret;
 
-        /*
-         * This lock_kernel fixes a subtle race with suid exec
-         */
-        lock_kernel();
         if (request == PTRACE_TRACEME) {
                 ret = ptrace_traceme();
                 if (!ret)
@@ -703,7 +723,6 @@ SYSCALL_DEFINE4(ptrace, long, request, long, pid, long, addr, long, data)
  out_put_task_struct:
         put_task_struct(child);
  out:
-        unlock_kernel();
         return ret;
 }
 
@@ -813,10 +832,6 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
         struct task_struct *child;
         long ret;
 
-        /*
-         * This lock_kernel fixes a subtle race with suid exec
-         */
-        lock_kernel();
         if (request == PTRACE_TRACEME) {
                 ret = ptrace_traceme();
                 goto out;
@@ -846,7 +861,6 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
  out_put_task_struct:
         put_task_struct(child);
  out:
-        unlock_kernel();
         return ret;
 }
 #endif  /* CONFIG_COMPAT */
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index 49d808e833b0..72a8dc9567f5 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -44,7 +44,6 @@
 #include <linux/cpu.h>
 #include <linux/mutex.h>
 #include <linux/module.h>
-#include <linux/kernel_stat.h>
 #include <linux/hardirq.h>
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -64,9 +63,6 @@ struct lockdep_map rcu_sched_lock_map =
 EXPORT_SYMBOL_GPL(rcu_sched_lock_map);
 #endif
 
-int rcu_scheduler_active __read_mostly;
-EXPORT_SYMBOL_GPL(rcu_scheduler_active);
-
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 
 int debug_lockdep_rcu_enabled(void)
@@ -97,21 +93,6 @@ EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held);
 #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
 /*
- * This function is invoked towards the end of the scheduler's initialization
- * process.  Before this is called, the idle task might contain
- * RCU read-side critical sections (during which time, this idle
- * task is booting the system).  After this function is called, the
- * idle tasks are prohibited from containing RCU read-side critical
- * sections.
- */
-void rcu_scheduler_starting(void)
-{
-        WARN_ON(num_online_cpus() != 1);
-        WARN_ON(nr_context_switches() > 0);
-        rcu_scheduler_active = 1;
-}
-
-/*
  * Awaken the corresponding synchronize_rcu() instance now that a
  * grace period has elapsed.
  */
diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c
index 9f6d9ff2572c..38729d3cd236 100644
--- a/kernel/rcutiny.c
+++ b/kernel/rcutiny.c
@@ -44,9 +44,9 @@ struct rcu_ctrlblk {
 };
 
 /* Definition for rcupdate control block. */
-static struct rcu_ctrlblk rcu_ctrlblk = {
-        .donetail       = &rcu_ctrlblk.rcucblist,
-        .curtail        = &rcu_ctrlblk.rcucblist,
+static struct rcu_ctrlblk rcu_sched_ctrlblk = {
+        .donetail       = &rcu_sched_ctrlblk.rcucblist,
+        .curtail        = &rcu_sched_ctrlblk.rcucblist,
 };
 
 static struct rcu_ctrlblk rcu_bh_ctrlblk = {
@@ -54,6 +54,11 @@ static struct rcu_ctrlblk rcu_bh_ctrlblk = {
         .curtail        = &rcu_bh_ctrlblk.rcucblist,
 };
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+int rcu_scheduler_active __read_mostly;
+EXPORT_SYMBOL_GPL(rcu_scheduler_active);
+#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+
 #ifdef CONFIG_NO_HZ
 
 static long rcu_dynticks_nesting = 1;
@@ -108,7 +113,8 @@ static int rcu_qsctr_help(struct rcu_ctrlblk *rcp)
  */
 void rcu_sched_qs(int cpu)
 {
-        if (rcu_qsctr_help(&rcu_ctrlblk) + rcu_qsctr_help(&rcu_bh_ctrlblk))
+        if (rcu_qsctr_help(&rcu_sched_ctrlblk) +
+            rcu_qsctr_help(&rcu_bh_ctrlblk))
                 raise_softirq(RCU_SOFTIRQ);
 }
 
@@ -173,7 +179,7 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp)
  */
 static void rcu_process_callbacks(struct softirq_action *unused)
 {
-        __rcu_process_callbacks(&rcu_ctrlblk);
+        __rcu_process_callbacks(&rcu_sched_ctrlblk);
         __rcu_process_callbacks(&rcu_bh_ctrlblk);
 }
 
@@ -187,7 +193,8 @@ static void rcu_process_callbacks(struct softirq_action *unused)
  *
  * Cool, huh?  (Due to Josh Triplett.)
  *
- * But we want to make this a static inline later.
+ * But we want to make this a static inline later.  The cond_resched()
+ * currently makes this problematic.
  */
 void synchronize_sched(void)
 {
@@ -195,12 +202,6 @@ void synchronize_sched(void)
 }
 EXPORT_SYMBOL_GPL(synchronize_sched);
 
-void synchronize_rcu_bh(void)
-{
-        synchronize_sched();
-}
-EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
-
 /*
  * Helper function for call_rcu() and call_rcu_bh().
  */
@@ -226,7 +227,7 @@ static void __call_rcu(struct rcu_head *head,
  */
 void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
 {
-        __call_rcu(head, func, &rcu_ctrlblk);
+        __call_rcu(head, func, &rcu_sched_ctrlblk);
 }
 EXPORT_SYMBOL_GPL(call_rcu);
 
@@ -244,11 +245,13 @@ void rcu_barrier(void)
 {
         struct rcu_synchronize rcu;
 
+        init_rcu_head_on_stack(&rcu.head);
         init_completion(&rcu.completion);
         /* Will wake me after RCU finished. */
         call_rcu(&rcu.head, wakeme_after_rcu);
         /* Wait for it. */
         wait_for_completion(&rcu.completion);
+        destroy_rcu_head_on_stack(&rcu.head);
 }
 EXPORT_SYMBOL_GPL(rcu_barrier);
 
@@ -256,11 +259,13 @@ void rcu_barrier_bh(void)
 {
         struct rcu_synchronize rcu;
 
+        init_rcu_head_on_stack(&rcu.head);
         init_completion(&rcu.completion);
         /* Will wake me after RCU finished. */
         call_rcu_bh(&rcu.head, wakeme_after_rcu);
         /* Wait for it. */
         wait_for_completion(&rcu.completion);
+        destroy_rcu_head_on_stack(&rcu.head);
 }
 EXPORT_SYMBOL_GPL(rcu_barrier_bh);
 
@@ -268,11 +273,13 @@ void rcu_barrier_sched(void)
 {
         struct rcu_synchronize rcu;
 
+        init_rcu_head_on_stack(&rcu.head);
         init_completion(&rcu.completion);
         /* Will wake me after RCU finished. */
         call_rcu_sched(&rcu.head, wakeme_after_rcu);
         /* Wait for it. */
         wait_for_completion(&rcu.completion);
+        destroy_rcu_head_on_stack(&rcu.head);
 }
 EXPORT_SYMBOL_GPL(rcu_barrier_sched);
 
@@ -280,3 +287,5 @@ void __init rcu_init(void)
 {
         open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
 }
+
+#include "rcutiny_plugin.h"
diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h
new file mode 100644
index 000000000000..d223a92bc742
--- /dev/null
+++ b/kernel/rcutiny_plugin.h
@@ -0,0 +1,39 @@
+/*
+ * Read-Copy Update mechanism for mutual exclusion (tree-based version)
+ * Internal non-public definitions that provide either classic
+ * or preemptable semantics.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2009
+ *
+ * Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+ */
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+#include <linux/kernel_stat.h>
+
+/*
+ * During boot, we forgive RCU lockdep issues.  After this function is
+ * invoked, we start taking RCU lockdep issues seriously.
+ */
+void rcu_scheduler_starting(void)
+{
+        WARN_ON(nr_context_switches() > 0);
+        rcu_scheduler_active = 1;
+}
+
+#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 58df55bf83ed..6535ac8bc6a5 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -464,9 +464,11 @@ static void rcu_bh_torture_synchronize(void)
 {
         struct rcu_bh_torture_synchronize rcu;
 
+        init_rcu_head_on_stack(&rcu.head);
         init_completion(&rcu.completion);
         call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb);
         wait_for_completion(&rcu.completion);
+        destroy_rcu_head_on_stack(&rcu.head);
 }
 
 static struct rcu_torture_ops rcu_bh_ops = {
@@ -669,7 +671,7 @@ static struct rcu_torture_ops sched_expedited_ops = {
         .sync           = synchronize_sched_expedited,
         .cb_barrier     = NULL,
         .fqs            = rcu_sched_force_quiescent_state,
-        .stats          = rcu_expedited_torture_stats,
+        .stats          = NULL,
         .irq_capable    = 1,
         .name           = "sched_expedited"
 };
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 3ec8160fc75f..d4437345706f 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -46,6 +46,7 @@
 #include <linux/cpu.h>
 #include <linux/mutex.h>
 #include <linux/time.h>
+#include <linux/kernel_stat.h>
 
 #include "rcutree.h"
 
@@ -53,8 +54,8 @@
 
 static struct lock_class_key rcu_node_class[NUM_RCU_LVLS];
 
-#define RCU_STATE_INITIALIZER(name) { \
-        .level = { &name.node[0] }, \
+#define RCU_STATE_INITIALIZER(structname) { \
+        .level = { &structname.node[0] }, \
         .levelcnt = { \
                 NUM_RCU_LVL_0,  /* root of hierarchy. */ \
                 NUM_RCU_LVL_1, \
@@ -65,13 +66,14 @@ static struct lock_class_key rcu_node_class[NUM_RCU_LVLS];
         .signaled = RCU_GP_IDLE, \
         .gpnum = -300, \
         .completed = -300, \
-        .onofflock = __RAW_SPIN_LOCK_UNLOCKED(&name.onofflock), \
+        .onofflock = __RAW_SPIN_LOCK_UNLOCKED(&structname.onofflock), \
         .orphan_cbs_list = NULL, \
-        .orphan_cbs_tail = &name.orphan_cbs_list, \
+        .orphan_cbs_tail = &structname.orphan_cbs_list, \
         .orphan_qlen = 0, \
-        .fqslock = __RAW_SPIN_LOCK_UNLOCKED(&name.fqslock), \
+        .fqslock = __RAW_SPIN_LOCK_UNLOCKED(&structname.fqslock), \
         .n_force_qs = 0, \
         .n_force_qs_ngp = 0, \
+        .name = #structname, \
 }
 
 struct rcu_state rcu_sched_state = RCU_STATE_INITIALIZER(rcu_sched_state);
@@ -80,6 +82,9 @@ DEFINE_PER_CPU(struct rcu_data, rcu_sched_data);
 struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh_state);
 DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
 
+int rcu_scheduler_active __read_mostly;
+EXPORT_SYMBOL_GPL(rcu_scheduler_active);
+
 /*
  * Return true if an RCU grace period is in progress.  The ACCESS_ONCE()s
  * permit this function to be invoked without holding the root rcu_node
@@ -97,25 +102,32 @@ static int rcu_gp_in_progress(struct rcu_state *rsp)
  */
 void rcu_sched_qs(int cpu)
 {
-        struct rcu_data *rdp;
+        struct rcu_data *rdp = &per_cpu(rcu_sched_data, cpu);
 
-        rdp = &per_cpu(rcu_sched_data, cpu);
         rdp->passed_quiesc_completed = rdp->gpnum - 1;
         barrier();
         rdp->passed_quiesc = 1;
-        rcu_preempt_note_context_switch(cpu);
 }
 
 void rcu_bh_qs(int cpu)
 {
-        struct rcu_data *rdp;
+        struct rcu_data *rdp = &per_cpu(rcu_bh_data, cpu);
 
-        rdp = &per_cpu(rcu_bh_data, cpu);
         rdp->passed_quiesc_completed = rdp->gpnum - 1;
         barrier();
         rdp->passed_quiesc = 1;
 }
 
+/*
+ * Note a context switch.  This is a quiescent state for RCU-sched,
+ * and requires special handling for preemptible RCU.
+ */
+void rcu_note_context_switch(int cpu)
+{
+        rcu_sched_qs(cpu);
+        rcu_preempt_note_context_switch(cpu);
+}
+
 #ifdef CONFIG_NO_HZ
 DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = {
         .dynticks_nesting = 1,
@@ -438,6 +450,8 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
 
 #ifdef CONFIG_RCU_CPU_STALL_DETECTOR
 
+int rcu_cpu_stall_panicking __read_mostly;
+
 static void record_gp_stall_check_time(struct rcu_state *rsp)
 {
         rsp->gp_start = jiffies;
@@ -470,7 +484,8 @@ static void print_other_cpu_stall(struct rcu_state *rsp)
 
         /* OK, time to rat on our buddy... */
 
-        printk(KERN_ERR "INFO: RCU detected CPU stalls:");
+        printk(KERN_ERR "INFO: %s detected stalls on CPUs/tasks: {",
+               rsp->name);
         rcu_for_each_leaf_node(rsp, rnp) {
                 raw_spin_lock_irqsave(&rnp->lock, flags);
                 rcu_print_task_stall(rnp);
@@ -481,7 +496,7 @@ static void print_other_cpu_stall(struct rcu_state *rsp)
                         if (rnp->qsmask & (1UL << cpu))
                                 printk(" %d", rnp->grplo + cpu);
         }
-        printk(" (detected by %d, t=%ld jiffies)\n",
+        printk("} (detected by %d, t=%ld jiffies)\n",
                smp_processor_id(), (long)(jiffies - rsp->gp_start));
         trigger_all_cpu_backtrace();
 
@@ -497,8 +512,8 @@ static void print_cpu_stall(struct rcu_state *rsp)
         unsigned long flags;
         struct rcu_node *rnp = rcu_get_root(rsp);
 
-        printk(KERN_ERR "INFO: RCU detected CPU %d stall (t=%lu jiffies)\n",
-                        smp_processor_id(), jiffies - rsp->gp_start);
+        printk(KERN_ERR "INFO: %s detected stall on CPU %d (t=%lu jiffies)\n",
+               rsp->name, smp_processor_id(), jiffies - rsp->gp_start);
         trigger_all_cpu_backtrace();
 
         raw_spin_lock_irqsave(&rnp->lock, flags);
@@ -515,6 +530,8 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
         long delta;
         struct rcu_node *rnp;
 
+        if (rcu_cpu_stall_panicking)
+                return;
         delta = jiffies - rsp->jiffies_stall;
         rnp = rdp->mynode;
         if ((rnp->qsmask & rdp->grpmask) && delta >= 0) {
@@ -529,6 +546,21 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
         }
 }
 
+static int rcu_panic(struct notifier_block *this, unsigned long ev, void *ptr)
+{
+        rcu_cpu_stall_panicking = 1;
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block rcu_panic_block = {
+        .notifier_call = rcu_panic,
+};
+
+static void __init check_cpu_stall_init(void)
+{
+        atomic_notifier_chain_register(&panic_notifier_list, &rcu_panic_block);
+}
+
 #else /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
 
 static void record_gp_stall_check_time(struct rcu_state *rsp)
@@ -539,6 +571,10 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
 {
 }
 
+static void __init check_cpu_stall_init(void)
+{
+}
+
 #endif /* #else #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
 
 /*
@@ -1125,8 +1161,6 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
  */
 void rcu_check_callbacks(int cpu, int user)
 {
-        if (!rcu_pending(cpu))
-                return; /* if nothing for RCU to do. */
         if (user ||
             (idle_cpu(cpu) && rcu_scheduler_active &&
              !in_softirq() && hardirq_count() <= (1 << HARDIRQ_SHIFT))) {
@@ -1158,7 +1192,8 @@ void rcu_check_callbacks(int cpu, int user)
                 rcu_bh_qs(cpu);
         }
         rcu_preempt_check_callbacks(cpu);
-        raise_softirq(RCU_SOFTIRQ);
+        if (rcu_pending(cpu))
+                raise_softirq(RCU_SOFTIRQ);
 }
 
 #ifdef CONFIG_SMP
@@ -1236,11 +1271,11 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed)
                 break; /* grace period idle or initializing, ignore. */
 
         case RCU_SAVE_DYNTICK:
-
-                raw_spin_unlock(&rnp->lock);  /* irqs remain disabled */
                 if (RCU_SIGNAL_INIT != RCU_SAVE_DYNTICK)
                         break; /* So gcc recognizes the dead code. */
 
+                raw_spin_unlock(&rnp->lock);  /* irqs remain disabled */
+
                 /* Record dyntick-idle state. */
                 force_qs_rnp(rsp, dyntick_save_progress_counter);
                 raw_spin_lock(&rnp->lock);  /* irqs already disabled */
@@ -1449,11 +1484,13 @@ void synchronize_sched(void)
         if (rcu_blocking_is_gp())
                 return;
 
+        init_rcu_head_on_stack(&rcu.head);
         init_completion(&rcu.completion);
         /* Will wake me after RCU finished. */
         call_rcu_sched(&rcu.head, wakeme_after_rcu);
         /* Wait for it. */
         wait_for_completion(&rcu.completion);
+        destroy_rcu_head_on_stack(&rcu.head);
 }
 EXPORT_SYMBOL_GPL(synchronize_sched);
 
@@ -1473,11 +1510,13 @@ void synchronize_rcu_bh(void)
         if (rcu_blocking_is_gp())
                 return;
 
+        init_rcu_head_on_stack(&rcu.head);
         init_completion(&rcu.completion);
         /* Will wake me after RCU finished. */
         call_rcu_bh(&rcu.head, wakeme_after_rcu);
         /* Wait for it. */
         wait_for_completion(&rcu.completion);
+        destroy_rcu_head_on_stack(&rcu.head);
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
 
@@ -1498,8 +1537,20 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
         check_cpu_stall(rsp, rdp);
 
         /* Is the RCU core waiting for a quiescent state from this CPU? */
-        if (rdp->qs_pending) {
+        if (rdp->qs_pending && !rdp->passed_quiesc) {
+
+                /*
+                 * If force_quiescent_state() coming soon and this CPU
+                 * needs a quiescent state, and this is either RCU-sched
+                 * or RCU-bh, force a local reschedule.
+                 */
                 rdp->n_rp_qs_pending++;
+                if (!rdp->preemptable &&
+                    ULONG_CMP_LT(ACCESS_ONCE(rsp->jiffies_force_qs) - 1,
+                                 jiffies))
+                        set_need_resched();
+        } else if (rdp->qs_pending && rdp->passed_quiesc) {
+                rdp->n_rp_report_qs++;
                 return 1;
         }
 
@@ -1767,6 +1818,21 @@ static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
 }
 
 /*
+ * This function is invoked towards the end of the scheduler's initialization
+ * process.  Before this is called, the idle task might contain
+ * RCU read-side critical sections (during which time, this idle
+ * task is booting the system).  After this function is called, the
+ * idle tasks are prohibited from containing RCU read-side critical
+ * sections.  This function also enables RCU lockdep checking.
+ */
+void rcu_scheduler_starting(void)
+{
+        WARN_ON(num_online_cpus() != 1);
+        WARN_ON(nr_context_switches() > 0);
+        rcu_scheduler_active = 1;
+}
+
+/*
  * Compute the per-level fanout, either using the exact fanout specified
  * or balancing the tree, depending on CONFIG_RCU_FANOUT_EXACT.
  */
@@ -1849,6 +1915,14 @@ static void __init rcu_init_one(struct rcu_state *rsp)
                         INIT_LIST_HEAD(&rnp->blocked_tasks[3]);
                 }
         }
+
+        rnp = rsp->level[NUM_RCU_LVLS - 1];
+        for_each_possible_cpu(i) {
+                while (i > rnp->grphi)
+                        rnp++;
+                rsp->rda[i]->mynode = rnp;
+                rcu_boot_init_percpu_data(i, rsp);
+        }
 }
 
 /*
@@ -1859,19 +1933,11 @@ static void __init rcu_init_one(struct rcu_state *rsp)
 #define RCU_INIT_FLAVOR(rsp, rcu_data) \
 do { \
         int i; \
-        int j; \
-        struct rcu_node *rnp; \
         \
-        rcu_init_one(rsp); \
-        rnp = (rsp)->level[NUM_RCU_LVLS - 1]; \
-        j = 0; \
         for_each_possible_cpu(i) { \
-                if (i > rnp[j].grphi) \
-                        j++; \
-                per_cpu(rcu_data, i).mynode = &rnp[j]; \
                 (rsp)->rda[i] = &per_cpu(rcu_data, i); \
-                rcu_boot_init_percpu_data(i, rsp); \
         } \
+        rcu_init_one(rsp); \
 } while (0)
 
 void __init rcu_init(void)
@@ -1879,12 +1945,6 @@ void __init rcu_init(void)
         int cpu;
 
         rcu_bootup_announce();
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-        printk(KERN_INFO "RCU-based detection of stalled CPUs is enabled.\n");
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-#if NUM_RCU_LVL_4 != 0
-        printk(KERN_INFO "Experimental four-level hierarchy is enabled.\n");
-#endif /* #if NUM_RCU_LVL_4 != 0 */
         RCU_INIT_FLAVOR(&rcu_sched_state, rcu_sched_data);
         RCU_INIT_FLAVOR(&rcu_bh_state, rcu_bh_data);
         __rcu_init_preempt();
@@ -1898,6 +1958,7 @@ void __init rcu_init(void)
         cpu_notifier(rcu_cpu_notify, 0);
         for_each_online_cpu(cpu)
                 rcu_cpu_notify(NULL, CPU_UP_PREPARE, (void *)(long)cpu);
+        check_cpu_stall_init();
 }
 
 #include "rcutree_plugin.h"
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 4a525a30e08e..14c040b18ed0 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -223,6 +223,7 @@ struct rcu_data {
         /* 5) __rcu_pending() statistics. */
         unsigned long n_rcu_pending;    /* rcu_pending() calls since boot. */
         unsigned long n_rp_qs_pending;
+        unsigned long n_rp_report_qs;
         unsigned long n_rp_cb_ready;
         unsigned long n_rp_cpu_needs_gp;
         unsigned long n_rp_gp_completed;
@@ -326,6 +327,7 @@ struct rcu_state {
         unsigned long jiffies_stall;            /* Time at which to check */
                                                 /*  for CPU stalls. */
 #endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+        char *name;                             /* Name of structure. */
 };
 
 /* Return values for rcu_preempt_offline_tasks(). */
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 79b53bda8943..0e4f420245d9 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -26,6 +26,45 @@
 
 #include <linux/delay.h>
 
+/*
+ * Check the RCU kernel configuration parameters and print informative
+ * messages about anything out of the ordinary.  If you like #ifdef, you
+ * will love this function.
+ */
+static void __init rcu_bootup_announce_oddness(void)
+{
+#ifdef CONFIG_RCU_TRACE
+        printk(KERN_INFO "\tRCU debugfs-based tracing is enabled.\n");
+#endif
+#if (defined(CONFIG_64BIT) && CONFIG_RCU_FANOUT != 64) || (!defined(CONFIG_64BIT) && CONFIG_RCU_FANOUT != 32)
+        printk(KERN_INFO "\tCONFIG_RCU_FANOUT set to non-default value of %d\n",
+               CONFIG_RCU_FANOUT);
+#endif
+#ifdef CONFIG_RCU_FANOUT_EXACT
+        printk(KERN_INFO "\tHierarchical RCU autobalancing is disabled.\n");
+#endif
+#ifdef CONFIG_RCU_FAST_NO_HZ
+        printk(KERN_INFO
+               "\tRCU dyntick-idle grace-period acceleration is enabled.\n");
+#endif
+#ifdef CONFIG_PROVE_RCU
+        printk(KERN_INFO "\tRCU lockdep checking is enabled.\n");
+#endif
+#ifdef CONFIG_RCU_TORTURE_TEST_RUNNABLE
+        printk(KERN_INFO "\tRCU torture testing starts during boot.\n");
+#endif
+#ifndef CONFIG_RCU_CPU_STALL_DETECTOR
+        printk(KERN_INFO
+               "\tRCU-based detection of stalled CPUs is disabled.\n");
+#endif
+#ifndef CONFIG_RCU_CPU_STALL_VERBOSE
+        printk(KERN_INFO "\tVerbose stalled-CPUs detection is disabled.\n");
+#endif
+#if NUM_RCU_LVL_4 != 0
+        printk(KERN_INFO "\tExperimental four-level hierarchy is enabled.\n");
+#endif
+}
+
 #ifdef CONFIG_TREE_PREEMPT_RCU
 
 struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt_state);
@@ -38,8 +77,8 @@ static int rcu_preempted_readers_exp(struct rcu_node *rnp);
  */
 static void __init rcu_bootup_announce(void)
 {
-        printk(KERN_INFO
-               "Experimental preemptable hierarchical RCU implementation.\n");
+        printk(KERN_INFO "Preemptable hierarchical RCU implementation.\n");
+        rcu_bootup_announce_oddness();
 }
 
 /*
@@ -75,13 +114,19 @@ EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
  * that this just means that the task currently running on the CPU is
  * not in a quiescent state.  There might be any number of tasks blocked
  * while in an RCU read-side critical section.
+ *
+ * Unlike the other rcu_*_qs() functions, callers to this function
+ * must disable irqs in order to protect the assignment to
+ * ->rcu_read_unlock_special.
  */
 static void rcu_preempt_qs(int cpu)
 {
         struct rcu_data *rdp = &per_cpu(rcu_preempt_data, cpu);
+
         rdp->passed_quiesc_completed = rdp->gpnum - 1;
         barrier();
         rdp->passed_quiesc = 1;
+        current->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
 }
 
 /*
@@ -144,9 +189,8 @@ static void rcu_preempt_note_context_switch(int cpu)
          * grace period, then the fact that the task has been enqueued
          * means that we continue to block the current grace period.
          */
-        rcu_preempt_qs(cpu);
         local_irq_save(flags);
-        t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+        rcu_preempt_qs(cpu);
         local_irq_restore(flags);
 }
 
@@ -236,7 +280,6 @@ static void rcu_read_unlock_special(struct task_struct *t)
          */
         special = t->rcu_read_unlock_special;
         if (special & RCU_READ_UNLOCK_NEED_QS) {
-                t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
                 rcu_preempt_qs(smp_processor_id());
         }
 
@@ -473,7 +516,6 @@ static void rcu_preempt_check_callbacks(int cpu)
         struct task_struct *t = current;
 
         if (t->rcu_read_lock_nesting == 0) {
-                t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
                 rcu_preempt_qs(cpu);
                 return;
         }
@@ -515,11 +557,13 @@ void synchronize_rcu(void)
         if (!rcu_scheduler_active)
                 return;
 
+        init_rcu_head_on_stack(&rcu.head);
         init_completion(&rcu.completion);
         /* Will wake me after RCU finished. */
         call_rcu(&rcu.head, wakeme_after_rcu);
         /* Wait for it. */
         wait_for_completion(&rcu.completion);
+        destroy_rcu_head_on_stack(&rcu.head);
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu);
 
@@ -754,6 +798,7 @@ void exit_rcu(void)
 static void __init rcu_bootup_announce(void)
 {
         printk(KERN_INFO "Hierarchical RCU implementation.\n");
+        rcu_bootup_announce_oddness();
 }
 
 /*
@@ -1008,6 +1053,8 @@ static DEFINE_PER_CPU(unsigned long, rcu_dyntick_holdoff);
 int rcu_needs_cpu(int cpu)
 {
         int c = 0;
+        int snap;
+        int snap_nmi;
         int thatcpu;
 
         /* Check for being in the holdoff period. */
@@ -1015,12 +1062,18 @@ int rcu_needs_cpu(int cpu)
                 return rcu_needs_cpu_quick_check(cpu);
 
         /* Don't bother unless we are the last non-dyntick-idle CPU. */
-        for_each_cpu_not(thatcpu, nohz_cpu_mask)
-                if (thatcpu != cpu) {
+        for_each_online_cpu(thatcpu) {
+                if (thatcpu == cpu)
+                        continue;
+                snap = per_cpu(rcu_dynticks, thatcpu).dynticks;
+                snap_nmi = per_cpu(rcu_dynticks, thatcpu).dynticks_nmi;
+                smp_mb(); /* Order sampling of snap with end of grace period. */
+                if (((snap & 0x1) != 0) || ((snap_nmi & 0x1) != 0)) {
                         per_cpu(rcu_dyntick_drain, cpu) = 0;
                         per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1;
                         return rcu_needs_cpu_quick_check(cpu);
                 }
+        }
 
         /* Check and update the rcu_dyntick_drain sequencing. */
         if (per_cpu(rcu_dyntick_drain, cpu) <= 0) {
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index d45db2e35d27..36c95b45738e 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -241,11 +241,13 @@ static const struct file_operations rcugp_fops = {
 static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp)
 {
         seq_printf(m, "%3d%cnp=%ld "
-                   "qsp=%ld cbr=%ld cng=%ld gpc=%ld gps=%ld nf=%ld nn=%ld\n",
+                   "qsp=%ld rpq=%ld cbr=%ld cng=%ld "
+                   "gpc=%ld gps=%ld nf=%ld nn=%ld\n",
                    rdp->cpu,
                    cpu_is_offline(rdp->cpu) ? '!' : ' ',
                    rdp->n_rcu_pending,
                    rdp->n_rp_qs_pending,
+                   rdp->n_rp_report_qs,
                    rdp->n_rp_cb_ready,
                    rdp->n_rp_cpu_needs_gp,
                    rdp->n_rp_gp_completed,
diff --git a/kernel/relay.c b/kernel/relay.c
index 3d97f2821611..c7cf397fb929 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -539,7 +539,7 @@ static int __cpuinit relay_hotcpu_callback(struct notifier_block *nb,
                                         "relay_hotcpu_callback: cpu %d buffer "
                                         "creation failed\n", hotcpu);
                                 mutex_unlock(&relay_channels_mutex);
-                                return NOTIFY_BAD;
+                                return notifier_from_errno(-ENOMEM);
                         }
                 }
                 mutex_unlock(&relay_channels_mutex);
@@ -1231,8 +1231,8 @@ static ssize_t subbuf_splice_actor(struct file *in,
         size_t read_subbuf = read_start / subbuf_size;
         size_t padding = rbuf->padding[read_subbuf];
         size_t nonpad_end = read_subbuf * subbuf_size + subbuf_size - padding;
-        struct page *pages[PIPE_BUFFERS];
-        struct partial_page partial[PIPE_BUFFERS];
+        struct page *pages[PIPE_DEF_BUFFERS];
+        struct partial_page partial[PIPE_DEF_BUFFERS];
         struct splice_pipe_desc spd = {
                 .pages = pages,
                 .nr_pages = 0,
@@ -1245,6 +1245,8 @@ static ssize_t subbuf_splice_actor(struct file *in,
 
         if (rbuf->subbufs_produced == rbuf->subbufs_consumed)
                 return 0;
+        if (splice_grow_spd(pipe, &spd))
+                return -ENOMEM;
 
         /*
          * Adjust read len, if longer than what is available
@@ -1255,7 +1257,7 @@ static ssize_t subbuf_splice_actor(struct file *in,
         subbuf_pages = rbuf->chan->alloc_size >> PAGE_SHIFT;
         pidx = (read_start / PAGE_SIZE) % subbuf_pages;
         poff = read_start & ~PAGE_MASK;
-        nr_pages = min_t(unsigned int, subbuf_pages, PIPE_BUFFERS);
+        nr_pages = min_t(unsigned int, subbuf_pages, pipe->buffers);
 
         for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) {
                 unsigned int this_len, this_end, private;
@@ -1289,16 +1291,19 @@ static ssize_t subbuf_splice_actor(struct file *in,
                 }
         }
 
+        ret = 0;
         if (!spd.nr_pages)
-                return 0;
+                goto out;
 
         ret = *nonpad_ret = splice_to_pipe(pipe, &spd);
         if (ret < 0 || ret < total_len)
-                return ret;
+                goto out;
 
         if (read_start + ret == nonpad_end)
                 ret += padding;
 
+out:
+        splice_shrink_spd(pipe, &spd);
         return ret;
 }
 
diff --git a/kernel/resource.c b/kernel/resource.c
index 9c358e263534..7b36976e5dea 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -15,6 +15,7 @@
 #include <linux/spinlock.h>
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
+#include <linux/sched.h>
 #include <linux/seq_file.h>
 #include <linux/device.h>
 #include <linux/pfn.h>
@@ -681,6 +682,8 @@ resource_size_t resource_alignment(struct resource *res)
  * release_region releases a matching busy region.
  */
 
+static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
+
 /**
  * __request_region - create a new busy resource region
  * @parent: parent resource descriptor
@@ -693,6 +696,7 @@ struct resource * __request_region(struct resource *parent,
                                    resource_size_t start, resource_size_t n,
                                    const char *name, int flags)
 {
+        DECLARE_WAITQUEUE(wait, current);
         struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
 
         if (!res)
@@ -717,7 +721,15 @@ struct resource * __request_region(struct resource *parent,
                         if (!(conflict->flags & IORESOURCE_BUSY))
                                 continue;
                 }
-
+                if (conflict->flags & flags & IORESOURCE_MUXED) {
+                        add_wait_queue(&muxed_resource_wait, &wait);
+                        write_unlock(&resource_lock);
+                        set_current_state(TASK_UNINTERRUPTIBLE);
+                        schedule();
+                        remove_wait_queue(&muxed_resource_wait, &wait);
+                        write_lock(&resource_lock);
+                        continue;
+                }
                 /* Uhhuh, that didn't work out.. */
                 kfree(res);
                 res = NULL;
@@ -791,6 +803,8 @@ void __release_region(struct resource *parent, resource_size_t start,
                                 break;
                         *p = res->sibling;
                         write_unlock(&resource_lock);
+                        if (res->flags & IORESOURCE_MUXED)
+                                wake_up(&muxed_resource_wait);
                         kfree(res);
                         return;
                 }
diff --git a/kernel/sched.c b/kernel/sched.c
index 3c2a54f70ffe..15b93f617fd7 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -55,9 +55,9 @@
 #include <linux/cpu.h>
 #include <linux/cpuset.h>
 #include <linux/percpu.h>
-#include <linux/kthread.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
+#include <linux/stop_machine.h>
 #include <linux/sysctl.h>
 #include <linux/syscalls.h>
 #include <linux/times.h>
@@ -503,8 +503,11 @@ struct rq {
         #define CPU_LOAD_IDX_MAX 5
         unsigned long cpu_load[CPU_LOAD_IDX_MAX];
 #ifdef CONFIG_NO_HZ
+        u64 nohz_stamp;
         unsigned char in_nohz_recently;
 #endif
+        unsigned int skip_clock_update;
+
         /* capture load from *all* tasks on this cpu: */
         struct load_weight load;
         unsigned long nr_load_updates;
@@ -546,15 +549,13 @@ struct rq {
         int post_schedule;
         int active_balance;
         int push_cpu;
+        struct cpu_stop_work active_balance_work;
         /* cpu of this runqueue: */
         int cpu;
         int online;
 
         unsigned long avg_load_per_task;
 
-        struct task_struct *migration_thread;
-        struct list_head migration_queue;
-
         u64 rt_avg;
         u64 age_stamp;
         u64 idle_stamp;
@@ -602,6 +603,13 @@ static inline
 void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
 {
         rq->curr->sched_class->check_preempt_curr(rq, p, flags);
+
+        /*
+         * A queue event has occurred, and we're going to schedule.  In
+         * this case, we can save a useless back to back clock update.
+         */
+        if (test_tsk_need_resched(p))
+                rq->skip_clock_update = 1;
 }
 
 static inline int cpu_of(struct rq *rq)
@@ -636,7 +644,8 @@ static inline int cpu_of(struct rq *rq)
 
 inline void update_rq_clock(struct rq *rq)
 {
-        rq->clock = sched_clock_cpu(cpu_of(rq));
+        if (!rq->skip_clock_update)
+                rq->clock = sched_clock_cpu(cpu_of(rq));
 }
 
 /*
@@ -914,16 +923,12 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
 #endif /* __ARCH_WANT_UNLOCKED_CTXSW */
 
 /*
- * Check whether the task is waking, we use this to synchronize against
- * ttwu() so that task_cpu() reports a stable number.
- *
- * We need to make an exception for PF_STARTING tasks because the fork
- * path might require task_rq_lock() to work, eg. it can call
- * set_cpus_allowed_ptr() from the cpuset clone_ns code.
+ * Check whether the task is waking, we use this to synchronize ->cpus_allowed
+ * against ttwu().
  */
 static inline int task_is_waking(struct task_struct *p)
 {
-        return unlikely((p->state == TASK_WAKING) && !(p->flags & PF_STARTING));
+        return unlikely(p->state == TASK_WAKING);
 }
 
 /*
@@ -936,11 +941,9 @@ static inline struct rq *__task_rq_lock(struct task_struct *p)
         struct rq *rq;
 
         for (;;) {
-                while (task_is_waking(p))
-                        cpu_relax();
                 rq = task_rq(p);
                 raw_spin_lock(&rq->lock);
-                if (likely(rq == task_rq(p) && !task_is_waking(p)))
+                if (likely(rq == task_rq(p)))
                         return rq;
                 raw_spin_unlock(&rq->lock);
         }
@@ -957,25 +960,15 @@ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
         struct rq *rq;
 
         for (;;) {
-                while (task_is_waking(p))
-                        cpu_relax();
                 local_irq_save(*flags);
                 rq = task_rq(p);
                 raw_spin_lock(&rq->lock);
-                if (likely(rq == task_rq(p) && !task_is_waking(p)))
+                if (likely(rq == task_rq(p)))
                         return rq;
                 raw_spin_unlock_irqrestore(&rq->lock, *flags);
         }
 }
 
-void task_rq_unlock_wait(struct task_struct *p)
-{
-        struct rq *rq = task_rq(p);
-
-        smp_mb(); /* spin-unlock-wait is not a full memory barrier */
-        raw_spin_unlock_wait(&rq->lock);
-}
-
 static void __task_rq_unlock(struct rq *rq)
         __releases(rq->lock)
 {
@@ -1239,6 +1232,17 @@ void wake_up_idle_cpu(int cpu)
         if (!tsk_is_polling(rq->idle))
                 smp_send_reschedule(cpu);
 }
+
+int nohz_ratelimit(int cpu)
+{
+        struct rq *rq = cpu_rq(cpu);
+        u64 diff = rq->clock - rq->nohz_stamp;
+
+        rq->nohz_stamp = rq->clock;
+
+        return diff < (NSEC_PER_SEC / HZ) >> 1;
+}
+
 #endif /* CONFIG_NO_HZ */
 
 static u64 sched_avg_period(void)
@@ -1781,8 +1785,6 @@ static void double_rq_lock(struct rq *rq1, struct rq *rq2)
                         raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
                 }
         }
-        update_rq_clock(rq1);
-        update_rq_clock(rq2);
 }
 
 /*
@@ -1813,7 +1815,7 @@ static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
 }
 #endif
 
-static void calc_load_account_active(struct rq *this_rq);
+static void calc_load_account_idle(struct rq *this_rq);
 static void update_sysctl(void);
 static int get_update_sysctl_factor(void);
 
@@ -1870,62 +1872,43 @@ static void set_load_weight(struct task_struct *p)
         p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO];
 }
 
-static void update_avg(u64 *avg, u64 sample)
-{
-        s64 diff = sample - *avg;
-        *avg += diff >> 3;
-}
-
-static void
-enqueue_task(struct rq *rq, struct task_struct *p, int wakeup, bool head)
+static void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
 {
-        if (wakeup)
-                p->se.start_runtime = p->se.sum_exec_runtime;
-
+        update_rq_clock(rq);
         sched_info_queued(p);
-        p->sched_class->enqueue_task(rq, p, wakeup, head);
+        p->sched_class->enqueue_task(rq, p, flags);
         p->se.on_rq = 1;
 }
 
-static void dequeue_task(struct rq *rq, struct task_struct *p, int sleep)
+static void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
 {
-        if (sleep) {
-                if (p->se.last_wakeup) {
-                        update_avg(&p->se.avg_overlap,
-                                p->se.sum_exec_runtime - p->se.last_wakeup);
-                        p->se.last_wakeup = 0;
-                } else {
-                        update_avg(&p->se.avg_wakeup,
-                                sysctl_sched_wakeup_granularity);
-                }
-        }
-
+        update_rq_clock(rq);
         sched_info_dequeued(p);
-        p->sched_class->dequeue_task(rq, p, sleep);
+        p->sched_class->dequeue_task(rq, p, flags);
         p->se.on_rq = 0;
 }
 
 /*
  * activate_task - move a task to the runqueue.
  */
-static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
+static void activate_task(struct rq *rq, struct task_struct *p, int flags)
 {
         if (task_contributes_to_load(p))
                 rq->nr_uninterruptible--;
 
-        enqueue_task(rq, p, wakeup, false);
+        enqueue_task(rq, p, flags);
         inc_nr_running(rq);
 }
 
 /*
  * deactivate_task - remove a task from the runqueue.
  */
-static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
+static void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
 {
         if (task_contributes_to_load(p))
                 rq->nr_uninterruptible++;
 
-        dequeue_task(rq, p, sleep);
+        dequeue_task(rq, p, flags);
         dec_nr_running(rq);
 }
 
@@ -2054,21 +2037,18 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
         __set_task_cpu(p, new_cpu);
 }
 
-struct migration_req {
-        struct list_head list;
-
+struct migration_arg {
         struct task_struct *task;
         int dest_cpu;
-
-        struct completion done;
 };
 
+static int migration_cpu_stop(void *data);
+
 /*
  * The task's runqueue lock must be held.
  * Returns true if you have to wait for migration thread.
  */
-static int
-migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req)
+static bool migrate_task(struct task_struct *p, int dest_cpu)
 {
         struct rq *rq = task_rq(p);
 
@@ -2076,58 +2056,7 @@ migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req)
          * If the task is not on a runqueue (and not running), then
          * the next wake-up will properly place the task.
          */
-        if (!p->se.on_rq && !task_running(rq, p))
-                return 0;
-
-        init_completion(&req->done);
-        req->task = p;
-        req->dest_cpu = dest_cpu;
-        list_add(&req->list, &rq->migration_queue);
-
-        return 1;
-}
-
-/*
- * wait_task_context_switch -   wait for a thread to complete at least one
- *                              context switch.
- *
- * @p must not be current.
- */
-void wait_task_context_switch(struct task_struct *p)
-{
-        unsigned long nvcsw, nivcsw, flags;
-        int running;
-        struct rq *rq;
-
-        nvcsw   = p->nvcsw;
-        nivcsw  = p->nivcsw;
-        for (;;) {
-                /*
-                 * The runqueue is assigned before the actual context
-                 * switch. We need to take the runqueue lock.
-                 *
-                 * We could check initially without the lock but it is
-                 * very likely that we need to take the lock in every
-                 * iteration.
-                 */
-                rq = task_rq_lock(p, &flags);
-                running = task_running(rq, p);
-                task_rq_unlock(rq, &flags);
-
-                if (likely(!running))
-                        break;
-                /*
-                 * The switch count is incremented before the actual
-                 * context switch. We thus wait for two switches to be
-                 * sure at least one completed.
-                 */
-                if ((p->nvcsw - nvcsw) > 1)
-                        break;
-                if ((p->nivcsw - nivcsw) > 1)
-                        break;
-
-                cpu_relax();
-        }
+        return p->se.on_rq || task_running(rq, p);
 }
 
 /*
@@ -2185,7 +2114,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
                  * just go back and repeat.
                  */
                 rq = task_rq_lock(p, &flags);
-                trace_sched_wait_task(rq, p);
+                trace_sched_wait_task(p);
                 running = task_running(rq, p);
                 on_rq = p->se.on_rq;
                 ncsw = 0;
@@ -2283,6 +2212,9 @@ void task_oncpu_function_call(struct task_struct *p,
 }
 
 #ifdef CONFIG_SMP
+/*
+ * ->cpus_allowed is protected by either TASK_WAKING or rq->lock held.
+ */
 static int select_fallback_rq(int cpu, struct task_struct *p)
 {
         int dest_cpu;
@@ -2299,12 +2231,8 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
                 return dest_cpu;
 
         /* No more Mr. Nice Guy. */
-        if (dest_cpu >= nr_cpu_ids) {
-                rcu_read_lock();
-                cpuset_cpus_allowed_locked(p, &p->cpus_allowed);
-                rcu_read_unlock();
-                dest_cpu = cpumask_any_and(cpu_active_mask, &p->cpus_allowed);
-
+        if (unlikely(dest_cpu >= nr_cpu_ids)) {
+                dest_cpu = cpuset_cpus_allowed_fallback(p);
                 /*
                  * Don't tell them about moving exiting tasks or
                  * kernel threads (both mm NULL), since they never
@@ -2321,17 +2249,12 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
 }
 
 /*
- * Gets called from 3 sites (exec, fork, wakeup), since it is called without
- * holding rq->lock we need to ensure ->cpus_allowed is stable, this is done
- * by:
- *
- *  exec:           is unstable, retry loop
- *  fork & wake-up: serialize ->cpus_allowed against TASK_WAKING
+ * The caller (fork, wakeup) owns TASK_WAKING, ->cpus_allowed is stable.
  */
 static inline
-int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
+int select_task_rq(struct rq *rq, struct task_struct *p, int sd_flags, int wake_flags)
 {
-        int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags);
+        int cpu = p->sched_class->select_task_rq(rq, p, sd_flags, wake_flags);
 
         /*
          * In order not to call set_task_cpu() on a blocking task we need
@@ -2349,6 +2272,12 @@ int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
 
         return cpu;
 }
+
+static void update_avg(u64 *avg, u64 sample)
+{
+        s64 diff = sample - *avg;
+        *avg += diff >> 3;
+}
 #endif
 
 /***
@@ -2370,16 +2299,13 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
 {
         int cpu, orig_cpu, this_cpu, success = 0;
         unsigned long flags;
+        unsigned long en_flags = ENQUEUE_WAKEUP;
         struct rq *rq;
 
-        if (!sched_feat(SYNC_WAKEUPS))
-                wake_flags &= ~WF_SYNC;
-
         this_cpu = get_cpu();
 
         smp_wmb();
         rq = task_rq_lock(p, &flags);
-        update_rq_clock(rq);
         if (!(p->state & state))
                 goto out;
 
@@ -2399,28 +2325,26 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
          *
          * First fix up the nr_uninterruptible count:
          */
-        if (task_contributes_to_load(p))
-                rq->nr_uninterruptible--;
+        if (task_contributes_to_load(p)) {
+                if (likely(cpu_online(orig_cpu)))
+                        rq->nr_uninterruptible--;
+                else
+                        this_rq()->nr_uninterruptible--;
+        }
         p->state = TASK_WAKING;
 
-        if (p->sched_class->task_waking)
+        if (p->sched_class->task_waking) {
                 p->sched_class->task_waking(rq, p);
+                en_flags |= ENQUEUE_WAKING;
+        }
 
-        __task_rq_unlock(rq);
-
-        cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
-        if (cpu != orig_cpu) {
-                /*
-                 * Since we migrate the task without holding any rq->lock,
-                 * we need to be careful with task_rq_lock(), since that
-                 * might end up locking an invalid rq.
-                 */
+        cpu = select_task_rq(rq, p, SD_BALANCE_WAKE, wake_flags);
+        if (cpu != orig_cpu)
                 set_task_cpu(p, cpu);
-        }
+        __task_rq_unlock(rq);
 
         rq = cpu_rq(cpu);
         raw_spin_lock(&rq->lock);
-        update_rq_clock(rq);
 
         /*
          * We migrated the task without holding either rq->lock, however
@@ -2448,36 +2372,20 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
 
 out_activate:
 #endif /* CONFIG_SMP */
-        schedstat_inc(p, se.nr_wakeups);
+        schedstat_inc(p, se.statistics.nr_wakeups);
         if (wake_flags & WF_SYNC)
-                schedstat_inc(p, se.nr_wakeups_sync);
+                schedstat_inc(p, se.statistics.nr_wakeups_sync);
         if (orig_cpu != cpu)
-                schedstat_inc(p, se.nr_wakeups_migrate);
+                schedstat_inc(p, se.statistics.nr_wakeups_migrate);
         if (cpu == this_cpu)
-                schedstat_inc(p, se.nr_wakeups_local);
+                schedstat_inc(p, se.statistics.nr_wakeups_local);
         else
-                schedstat_inc(p, se.nr_wakeups_remote);
-        activate_task(rq, p, 1);
+                schedstat_inc(p, se.statistics.nr_wakeups_remote);
+        activate_task(rq, p, en_flags);
         success = 1;
 
-        /*
-         * Only attribute actual wakeups done by this task.
-         */
-        if (!in_interrupt()) {
-                struct sched_entity *se = &current->se;
-                u64 sample = se->sum_exec_runtime;
-
-                if (se->last_wakeup)
-                        sample -= se->last_wakeup;
-                else
-                        sample -= se->start_runtime;
-                update_avg(&se->avg_wakeup, sample);
-
-                se->last_wakeup = se->sum_exec_runtime;
-        }
-
 out_running:
-        trace_sched_wakeup(rq, p, success);
+        trace_sched_wakeup(p, success);
         check_preempt_curr(rq, p, wake_flags);
 
         p->state = TASK_RUNNING;
@@ -2537,42 +2445,9 @@ static void __sched_fork(struct task_struct *p)
         p->se.sum_exec_runtime          = 0;
         p->se.prev_sum_exec_runtime     = 0;
         p->se.nr_migrations             = 0;
-        p->se.last_wakeup               = 0;
-        p->se.avg_overlap               = 0;
-        p->se.start_runtime             = 0;
-        p->se.avg_wakeup                = sysctl_sched_wakeup_granularity;
 
 #ifdef CONFIG_SCHEDSTATS
-        p->se.wait_start                        = 0;
-        p->se.wait_max                          = 0;
-        p->se.wait_count                        = 0;
-        p->se.wait_sum                          = 0;
-
-        p->se.sleep_start                       = 0;
-        p->se.sleep_max                         = 0;
-        p->se.sum_sleep_runtime                 = 0;
-
-        p->se.block_start                       = 0;
-        p->se.block_max                         = 0;
-        p->se.exec_max                          = 0;
-        p->se.slice_max                         = 0;
-
-        p->se.nr_migrations_cold                = 0;
-        p->se.nr_failed_migrations_affine       = 0;
-        p->se.nr_failed_migrations_running      = 0;
-        p->se.nr_failed_migrations_hot          = 0;
-        p->se.nr_forced_migrations              = 0;
-
-        p->se.nr_wakeups                        = 0;
-        p->se.nr_wakeups_sync                   = 0;
-        p->se.nr_wakeups_migrate                = 0;
-        p->se.nr_wakeups_local                  = 0;
-        p->se.nr_wakeups_remote                 = 0;
-        p->se.nr_wakeups_affine                 = 0;
-        p->se.nr_wakeups_affine_attempts        = 0;
-        p->se.nr_wakeups_passive                = 0;
-        p->se.nr_wakeups_idle                   = 0;
-
+        memset(&p->se.statistics, 0, sizeof(p->se.statistics));
 #endif
 
         INIT_LIST_HEAD(&p->rt.run_list);
@@ -2593,11 +2468,11 @@ void sched_fork(struct task_struct *p, int clone_flags)
 
         __sched_fork(p);
         /*
-         * We mark the process as waking here. This guarantees that
+         * We mark the process as running here. This guarantees that
          * nobody will actually run it, and a signal or other external
          * event cannot wake it up and insert it on the runqueue either.
          */
-        p->state = TASK_WAKING;
+        p->state = TASK_RUNNING;
 
         /*
          * Revert to default priority/policy on fork if requested.
@@ -2664,31 +2539,27 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
         int cpu __maybe_unused = get_cpu();
 
 #ifdef CONFIG_SMP
+        rq = task_rq_lock(p, &flags);
+        p->state = TASK_WAKING;
+
         /*
          * Fork balancing, do it here and not earlier because:
          *  - cpus_allowed can change in the fork path
          *  - any previously selected cpu might disappear through hotplug
          *
-         * We still have TASK_WAKING but PF_STARTING is gone now, meaning
-         * ->cpus_allowed is stable, we have preemption disabled, meaning
-         * cpu_online_mask is stable.
+         * We set TASK_WAKING so that select_task_rq() can drop rq->lock
+         * without people poking at ->cpus_allowed.
          */
-        cpu = select_task_rq(p, SD_BALANCE_FORK, 0);
+        cpu = select_task_rq(rq, p, SD_BALANCE_FORK, 0);
         set_task_cpu(p, cpu);
-#endif
-
-        /*
-         * Since the task is not on the rq and we still have TASK_WAKING set
-         * nobody else will migrate this task.
-         */
-        rq = cpu_rq(cpu);
-        raw_spin_lock_irqsave(&rq->lock, flags);
 
-        BUG_ON(p->state != TASK_WAKING);
         p->state = TASK_RUNNING;
-        update_rq_clock(rq);
+        task_rq_unlock(rq, &flags);
+#endif
+
+        rq = task_rq_lock(p, &flags);
         activate_task(rq, p, 0);
-        trace_sched_wakeup_new(rq, p, 1);
+        trace_sched_wakeup_new(p, 1);
         check_preempt_curr(rq, p, WF_FORK);
 #ifdef CONFIG_SMP
         if (p->sched_class->task_woken)
@@ -2908,7 +2779,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
         struct mm_struct *mm, *oldmm;
 
         prepare_task_switch(rq, prev, next);
-        trace_sched_switch(rq, prev, next);
+        trace_sched_switch(prev, next);
         mm = next->mm;
         oldmm = prev->active_mm;
         /*
@@ -3025,6 +2896,61 @@ static unsigned long calc_load_update;
 unsigned long avenrun[3];
 EXPORT_SYMBOL(avenrun);
 
+static long calc_load_fold_active(struct rq *this_rq)
+{
+        long nr_active, delta = 0;
+
+        nr_active = this_rq->nr_running;
+        nr_active += (long) this_rq->nr_uninterruptible;
+
+        if (nr_active != this_rq->calc_load_active) {
+                delta = nr_active - this_rq->calc_load_active;
+                this_rq->calc_load_active = nr_active;
+        }
+
+        return delta;
+}
+
+#ifdef CONFIG_NO_HZ
+/*
+ * For NO_HZ we delay the active fold to the next LOAD_FREQ update.
+ *
+ * When making the ILB scale, we should try to pull this in as well.
+ */
+static atomic_long_t calc_load_tasks_idle;
+
+static void calc_load_account_idle(struct rq *this_rq)
+{
+        long delta;
+
+        delta = calc_load_fold_active(this_rq);
+        if (delta)
+                atomic_long_add(delta, &calc_load_tasks_idle);
+}
+
+static long calc_load_fold_idle(void)
+{
+        long delta = 0;
+
+        /*
+         * Its got a race, we don't care...
+         */
+        if (atomic_long_read(&calc_load_tasks_idle))
+                delta = atomic_long_xchg(&calc_load_tasks_idle, 0);
+
+        return delta;
+}
+#else
+static void calc_load_account_idle(struct rq *this_rq)
+{
+}
+
+static inline long calc_load_fold_idle(void)
+{
+        return 0;
+}
+#endif
+
 /**
  * get_avenrun - get the load average array
  * @loads:      pointer to dest load array
@@ -3071,20 +2997,22 @@ void calc_global_load(void)
 }
 
 /*
- * Either called from update_cpu_load() or from a cpu going idle
+ * Called from update_cpu_load() to periodically update this CPU's
+ * active count.
  */
 static void calc_load_account_active(struct rq *this_rq)
 {
-        long nr_active, delta;
+        long delta;
 
-        nr_active = this_rq->nr_running;
-        nr_active += (long) this_rq->nr_uninterruptible;
+        if (time_before(jiffies, this_rq->calc_load_update))
+                return;
 
-        if (nr_active != this_rq->calc_load_active) {
-                delta = nr_active - this_rq->calc_load_active;
-                this_rq->calc_load_active = nr_active;
+        delta  = calc_load_fold_active(this_rq);
+        delta += calc_load_fold_idle();
+        if (delta)
                 atomic_long_add(delta, &calc_load_tasks);
-        }
+
+        this_rq->calc_load_update += LOAD_FREQ;
 }
 
 /*
@@ -3116,10 +3044,7 @@ static void update_cpu_load(struct rq *this_rq)
                 this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) >> i;
         }
 
-        if (time_after_eq(jiffies, this_rq->calc_load_update)) {
-                this_rq->calc_load_update += LOAD_FREQ;
-                calc_load_account_active(this_rq);
-        }
+        calc_load_account_active(this_rq);
 }
 
 #ifdef CONFIG_SMP
@@ -3131,44 +3056,27 @@ static void update_cpu_load(struct rq *this_rq)
 void sched_exec(void)
 {
         struct task_struct *p = current;
-        struct migration_req req;
-        int dest_cpu, this_cpu;
         unsigned long flags;
         struct rq *rq;
-
-again:
-        this_cpu = get_cpu();
-        dest_cpu = select_task_rq(p, SD_BALANCE_EXEC, 0);
-        if (dest_cpu == this_cpu) {
-                put_cpu();
-                return;
-        }
+        int dest_cpu;
 
         rq = task_rq_lock(p, &flags);
-        put_cpu();
+        dest_cpu = p->sched_class->select_task_rq(rq, p, SD_BALANCE_EXEC, 0);
+        if (dest_cpu == smp_processor_id())
+                goto unlock;
 
         /*
          * select_task_rq() can race against ->cpus_allowed
          */
-        if (!cpumask_test_cpu(dest_cpu, &p->cpus_allowed)
-            || unlikely(!cpu_active(dest_cpu))) {
-                task_rq_unlock(rq, &flags);
-                goto again;
-        }
+        if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed) &&
+            likely(cpu_active(dest_cpu)) && migrate_task(p, dest_cpu)) {
+                struct migration_arg arg = { p, dest_cpu };
 
-        /* force the process onto the specified CPU */
-        if (migrate_task(p, dest_cpu, &req)) {
-                /* Need to wait for migration thread (might exit: take ref). */
-                struct task_struct *mt = rq->migration_thread;
-
-                get_task_struct(mt);
                 task_rq_unlock(rq, &flags);
-                wake_up_process(mt);
-                put_task_struct(mt);
-                wait_for_completion(&req.done);
-
+                stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
                 return;
         }
+unlock:
         task_rq_unlock(rq, &flags);
 }
 
@@ -3640,23 +3548,9 @@ static inline void schedule_debug(struct task_struct *prev)
 
 static void put_prev_task(struct rq *rq, struct task_struct *prev)
 {
-        if (prev->state == TASK_RUNNING) {
-                u64 runtime = prev->se.sum_exec_runtime;
-
-                runtime -= prev->se.prev_sum_exec_runtime;
-                runtime = min_t(u64, runtime, 2*sysctl_sched_migration_cost);
-
-                /*
-                 * In order to avoid avg_overlap growing stale when we are
-                 * indeed overlapping and hence not getting put to sleep, grow
-                 * the avg_overlap on preemption.
-                 *
-                 * We use the average preemption runtime because that
-                 * correlates to the amount of cache footprint a task can
-                 * build up.
-                 */
-                update_avg(&prev->se.avg_overlap, runtime);
-        }
+        if (prev->se.on_rq)
+                update_rq_clock(rq);
+        rq->skip_clock_update = 0;
         prev->sched_class->put_prev_task(rq, prev);
 }
 
@@ -3706,7 +3600,7 @@ need_resched:
         preempt_disable();
         cpu = smp_processor_id();
         rq = cpu_rq(cpu);
-        rcu_sched_qs(cpu);
+        rcu_note_context_switch(cpu);
         prev = rq->curr;
         switch_count = &prev->nivcsw;
 
@@ -3719,14 +3613,13 @@ need_resched_nonpreemptible:
                 hrtick_clear(rq);
 
         raw_spin_lock_irq(&rq->lock);
-        update_rq_clock(rq);
         clear_tsk_need_resched(prev);
 
         if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
                 if (unlikely(signal_pending_state(prev->state, prev)))
                         prev->state = TASK_RUNNING;
                 else
-                        deactivate_task(rq, prev, 1);
+                        deactivate_task(rq, prev, DEQUEUE_SLEEP);
                 switch_count = &prev->nvcsw;
         }
 
@@ -3950,6 +3843,7 @@ void __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
 {
         __wake_up_common(q, mode, 1, 0, NULL);
 }
+EXPORT_SYMBOL_GPL(__wake_up_locked);
 
 void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key)
 {
@@ -4049,8 +3943,7 @@ do_wait_for_common(struct completion *x, long timeout, int state)
         if (!x->done) {
                 DECLARE_WAITQUEUE(wait, current);
 
-                wait.flags |= WQ_FLAG_EXCLUSIVE;
-                __add_wait_queue_tail(&x->wait, &wait);
+                __add_wait_queue_tail_exclusive(&x->wait, &wait);
                 do {
                         if (signal_pending_state(state, current)) {
                                 timeout = -ERESTARTSYS;
@@ -4276,7 +4169,6 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
         BUG_ON(prio < 0 || prio > MAX_PRIO);
 
         rq = task_rq_lock(p, &flags);
-        update_rq_clock(rq);
 
         oldprio = p->prio;
         prev_class = p->sched_class;
@@ -4297,7 +4189,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
         if (running)
                 p->sched_class->set_curr_task(rq);
         if (on_rq) {
-                enqueue_task(rq, p, 0, oldprio < prio);
+                enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0);
 
                 check_class_changed(rq, p, prev_class, oldprio, running);
         }
@@ -4319,7 +4211,6 @@ void set_user_nice(struct task_struct *p, long nice)
          * the task might be in the middle of scheduling on another CPU.
          */
         rq = task_rq_lock(p, &flags);
-        update_rq_clock(rq);
         /*
          * The RT priorities are set via sched_setscheduler(), but we still
          * allow the 'normal' nice value to be set - but as expected
@@ -4341,7 +4232,7 @@ void set_user_nice(struct task_struct *p, long nice)
         delta = p->prio - old_prio;
 
         if (on_rq) {
-                enqueue_task(rq, p, 0, false);
+                enqueue_task(rq, p, 0);
                 /*
                  * If the task increased its priority or is running and
                  * lowered its priority, then reschedule its CPU:
@@ -4602,7 +4493,6 @@ recheck:
                 raw_spin_unlock_irqrestore(&p->pi_lock, flags);
                 goto recheck;
         }
-        update_rq_clock(rq);
         on_rq = p->se.on_rq;
         running = task_current(rq, p);
         if (on_rq)
@@ -5339,17 +5229,15 @@ static inline void sched_init_granularity(void)
 /*
  * This is how migration works:
  *
- * 1) we queue a struct migration_req structure in the source CPU's
- *    runqueue and wake up that CPU's migration thread.
- * 2) we down() the locked semaphore => thread blocks.
- * 3) migration thread wakes up (implicitly it forces the migrated
- *    thread off the CPU)
- * 4) it gets the migration request and checks whether the migrated
- *    task is still in the wrong runqueue.
- * 5) if it's in the wrong runqueue then the migration thread removes
+ * 1) we invoke migration_cpu_stop() on the target CPU using
+ *    stop_one_cpu().
+ * 2) stopper starts to run (implicitly forcing the migrated thread
+ *    off the CPU)
+ * 3) it checks whether the migrated task is still in the wrong runqueue.
+ * 4) if it's in the wrong runqueue then the migration thread removes
  *    it and puts it into the right queue.
- * 6) migration thread up()s the semaphore.
- * 7) we wake up and the migration is done.
+ * 5) stopper completes and stop_one_cpu() returns and the migration
+ *    is done.
  */
 
 /*
@@ -5363,12 +5251,23 @@ static inline void sched_init_granularity(void)
  */
 int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
 {
-        struct migration_req req;
         unsigned long flags;
         struct rq *rq;
+        unsigned int dest_cpu;
         int ret = 0;
 
+        /*
+         * Serialize against TASK_WAKING so that ttwu() and wunt() can
+         * drop the rq->lock and still rely on ->cpus_allowed.
+         */
+again:
+        while (task_is_waking(p))
+                cpu_relax();
         rq = task_rq_lock(p, &flags);
+        if (task_is_waking(p)) {
+                task_rq_unlock(rq, &flags);
+                goto again;
+        }
 
         if (!cpumask_intersects(new_mask, cpu_active_mask)) {
                 ret = -EINVAL;
@@ -5392,15 +5291,12 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
         if (cpumask_test_cpu(task_cpu(p), new_mask))
                 goto out;
 
-        if (migrate_task(p, cpumask_any_and(cpu_active_mask, new_mask), &req)) {
+        dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
+        if (migrate_task(p, dest_cpu)) {
+                struct migration_arg arg = { p, dest_cpu };
                 /* Need help from migration thread: drop lock and wait. */
-                struct task_struct *mt = rq->migration_thread;
-
-                get_task_struct(mt);
                 task_rq_unlock(rq, &flags);
-                wake_up_process(mt);
-                put_task_struct(mt);
-                wait_for_completion(&req.done);
+                stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
                 tlb_migrate_finish(p->mm);
                 return 0;
         }
@@ -5458,98 +5354,49 @@ fail:
         return ret;
 }
 
-#define RCU_MIGRATION_IDLE      0
-#define RCU_MIGRATION_NEED_QS   1
-#define RCU_MIGRATION_GOT_QS    2
-#define RCU_MIGRATION_MUST_SYNC 3
-
 /*
- * migration_thread - this is a highprio system thread that performs
- * thread migration by bumping thread off CPU then 'pushing' onto
- * another runqueue.
+ * migration_cpu_stop - this will be executed by a highprio stopper thread
+ * and performs thread migration by bumping thread off CPU then
+ * 'pushing' onto another runqueue.
  */
-static int migration_thread(void *data)
-{
-        int badcpu;
-        int cpu = (long)data;
-        struct rq *rq;
-
-        rq = cpu_rq(cpu);
-        BUG_ON(rq->migration_thread != current);
-
-        set_current_state(TASK_INTERRUPTIBLE);
-        while (!kthread_should_stop()) {
-                struct migration_req *req;
-                struct list_head *head;
-
-                raw_spin_lock_irq(&rq->lock);
-
-                if (cpu_is_offline(cpu)) {
-                        raw_spin_unlock_irq(&rq->lock);
-                        break;
-                }
-
-                if (rq->active_balance) {
-                        active_load_balance(rq, cpu);
-                        rq->active_balance = 0;
-                }
-
-                head = &rq->migration_queue;
-
-                if (list_empty(head)) {
-                        raw_spin_unlock_irq(&rq->lock);
-                        schedule();
-                        set_current_state(TASK_INTERRUPTIBLE);
-                        continue;
-                }
-                req = list_entry(head->next, struct migration_req, list);
-                list_del_init(head->next);
-
-                if (req->task != NULL) {
-                        raw_spin_unlock(&rq->lock);
-                        __migrate_task(req->task, cpu, req->dest_cpu);
-                } else if (likely(cpu == (badcpu = smp_processor_id()))) {
-                        req->dest_cpu = RCU_MIGRATION_GOT_QS;
-                        raw_spin_unlock(&rq->lock);
-                } else {
-                        req->dest_cpu = RCU_MIGRATION_MUST_SYNC;
-                        raw_spin_unlock(&rq->lock);
-                        WARN_ONCE(1, "migration_thread() on CPU %d, expected %d\n", badcpu, cpu);
-                }
-                local_irq_enable();
-
-                complete(&req->done);
-        }
-        __set_current_state(TASK_RUNNING);
-
-        return 0;
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-static int __migrate_task_irq(struct task_struct *p, int src_cpu, int dest_cpu)
+static int migration_cpu_stop(void *data)
 {
-        int ret;
+        struct migration_arg *arg = data;
 
+        /*
+         * The original target cpu might have gone down and we might
+         * be on another cpu but it doesn't matter.
+         */
         local_irq_disable();
-        ret = __migrate_task(p, src_cpu, dest_cpu);
+        __migrate_task(arg->task, raw_smp_processor_id(), arg->dest_cpu);
         local_irq_enable();
-        return ret;
+        return 0;
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
 /*
  * Figure out where task on dead CPU should go, use force if necessary.
  */
-static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
+void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
 {
-        int dest_cpu;
+        struct rq *rq = cpu_rq(dead_cpu);
+        int needs_cpu, uninitialized_var(dest_cpu);
+        unsigned long flags;
 
-again:
-        dest_cpu = select_fallback_rq(dead_cpu, p);
+        local_irq_save(flags);
 
-        /* It can have affinity changed while we were choosing. */
-        if (unlikely(!__migrate_task_irq(p, dead_cpu, dest_cpu)))
-                goto again;
+        raw_spin_lock(&rq->lock);
+        needs_cpu = (task_cpu(p) == dead_cpu) && (p->state != TASK_WAKING);
+        if (needs_cpu)
+                dest_cpu = select_fallback_rq(dead_cpu, p);
+        raw_spin_unlock(&rq->lock);
+        /*
+         * It can only fail if we race with set_cpus_allowed(),
+         * in the racer should migrate the task anyway.
+         */
+        if (needs_cpu)
+                __migrate_task(p, dead_cpu, dest_cpu);
+        local_irq_restore(flags);
 }
 
 /*
@@ -5613,7 +5460,6 @@ void sched_idle_next(void)
 
         __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
 
-        update_rq_clock(rq);
         activate_task(rq, p, 0);
 
         raw_spin_unlock_irqrestore(&rq->lock, flags);
@@ -5668,7 +5514,6 @@ static void migrate_dead_tasks(unsigned int dead_cpu)
         for ( ; ; ) {
                 if (!rq->nr_running)
                         break;
-                update_rq_clock(rq);
                 next = pick_next_task(rq);
                 if (!next)
                         break;
@@ -5891,35 +5736,20 @@ static void set_rq_offline(struct rq *rq)
 static int __cpuinit
 migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 {
-        struct task_struct *p;
         int cpu = (long)hcpu;
         unsigned long flags;
-        struct rq *rq;
+        struct rq *rq = cpu_rq(cpu);
 
         switch (action) {
 
         case CPU_UP_PREPARE:
         case CPU_UP_PREPARE_FROZEN:
-                p = kthread_create(migration_thread, hcpu, "migration/%d", cpu);
-                if (IS_ERR(p))
-                        return NOTIFY_BAD;
-                kthread_bind(p, cpu);
-                /* Must be high prio: stop_machine expects to yield to it. */
-                rq = task_rq_lock(p, &flags);
-                __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
-                task_rq_unlock(rq, &flags);
-                get_task_struct(p);
-                cpu_rq(cpu)->migration_thread = p;
                 rq->calc_load_update = calc_load_update;
                 break;
 
         case CPU_ONLINE:
         case CPU_ONLINE_FROZEN:
-                /* Strictly unnecessary, as first user will wake it. */
-                wake_up_process(cpu_rq(cpu)->migration_thread);
-
                 /* Update our root-domain */
-                rq = cpu_rq(cpu);
                 raw_spin_lock_irqsave(&rq->lock, flags);
                 if (rq->rd) {
                         BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
@@ -5930,61 +5760,24 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
                 break;
 
 #ifdef CONFIG_HOTPLUG_CPU
-        case CPU_UP_CANCELED:
-        case CPU_UP_CANCELED_FROZEN:
-                if (!cpu_rq(cpu)->migration_thread)
-                        break;
-                /* Unbind it from offline cpu so it can run. Fall thru. */
-                kthread_bind(cpu_rq(cpu)->migration_thread,
-                             cpumask_any(cpu_online_mask));
-                kthread_stop(cpu_rq(cpu)->migration_thread);
-                put_task_struct(cpu_rq(cpu)->migration_thread);
-                cpu_rq(cpu)->migration_thread = NULL;
-                break;
-
         case CPU_DEAD:
         case CPU_DEAD_FROZEN:
-                cpuset_lock(); /* around calls to cpuset_cpus_allowed_lock() */
                 migrate_live_tasks(cpu);
-                rq = cpu_rq(cpu);
-                kthread_stop(rq->migration_thread);
-                put_task_struct(rq->migration_thread);
-                rq->migration_thread = NULL;
                 /* Idle task back to normal (off runqueue, low prio) */
                 raw_spin_lock_irq(&rq->lock);
-                update_rq_clock(rq);
                 deactivate_task(rq, rq->idle, 0);
                 __setscheduler(rq, rq->idle, SCHED_NORMAL, 0);
                 rq->idle->sched_class = &idle_sched_class;
                 migrate_dead_tasks(cpu);
                 raw_spin_unlock_irq(&rq->lock);
-                cpuset_unlock();
                 migrate_nr_uninterruptible(rq);
                 BUG_ON(rq->nr_running != 0);
                 calc_global_load_remove(rq);
-                /*
-                 * No need to migrate the tasks: it was best-effort if
-                 * they didn't take sched_hotcpu_mutex. Just wake up
-                 * the requestors.
-                 */
-                raw_spin_lock_irq(&rq->lock);
-                while (!list_empty(&rq->migration_queue)) {
-                        struct migration_req *req;
-
-                        req = list_entry(rq->migration_queue.next,
-                                         struct migration_req, list);
-                        list_del_init(&req->list);
-                        raw_spin_unlock_irq(&rq->lock);
-                        complete(&req->done);
-                        raw_spin_lock_irq(&rq->lock);
-                }
-                raw_spin_unlock_irq(&rq->lock);
                 break;
 
         case CPU_DYING:
         case CPU_DYING_FROZEN:
                 /* Update our root-domain */
-                rq = cpu_rq(cpu);
                 raw_spin_lock_irqsave(&rq->lock, flags);
                 if (rq->rd) {
                         BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
@@ -6315,6 +6108,9 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
         struct rq *rq = cpu_rq(cpu);
         struct sched_domain *tmp;
 
+        for (tmp = sd; tmp; tmp = tmp->parent)
+                tmp->span_weight = cpumask_weight(sched_domain_span(tmp));
+
         /* Remove the sched domains which do not contribute to scheduling. */
         for (tmp = sd; tmp; ) {
                 struct sched_domain *parent = tmp->parent;
@@ -7798,10 +7594,8 @@ void __init sched_init(void)
                 rq->push_cpu = 0;
                 rq->cpu = i;
                 rq->online = 0;
-                rq->migration_thread = NULL;
                 rq->idle_stamp = 0;
                 rq->avg_idle = 2*sysctl_sched_migration_cost;
-                INIT_LIST_HEAD(&rq->migration_queue);
                 rq_attach_root(rq, &def_root_domain);
 #endif
                 init_rq_hrtick(rq);
@@ -7902,7 +7696,6 @@ static void normalize_task(struct rq *rq, struct task_struct *p)
 {
         int on_rq;
 
-        update_rq_clock(rq);
         on_rq = p->se.on_rq;
         if (on_rq)
                 deactivate_task(rq, p, 0);
@@ -7929,9 +7722,9 @@ void normalize_rt_tasks(void)
 
                 p->se.exec_start                = 0;
 #ifdef CONFIG_SCHEDSTATS
-                p->se.wait_start                = 0;
-                p->se.sleep_start               = 0;
-                p->se.block_start               = 0;
+                p->se.statistics.wait_start     = 0;
+                p->se.statistics.sleep_start    = 0;
+                p->se.statistics.block_start    = 0;
 #endif
 
                 if (!rt_task(p)) {
@@ -7958,9 +7751,9 @@ void normalize_rt_tasks(void)
 
 #endif /* CONFIG_MAGIC_SYSRQ */
 
-#ifdef CONFIG_IA64
+#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB)
 /*
- * These functions are only useful for the IA64 MCA handling.
+ * These functions are only useful for the IA64 MCA handling, or kdb.
  *
  * They can only be called when the whole system has been
  * stopped - every CPU needs to be quiescent, and no scheduling
@@ -7980,6 +7773,9 @@ struct task_struct *curr_task(int cpu)
         return cpu_curr(cpu);
 }
 
+#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */
+
+#ifdef CONFIG_IA64
 /**
  * set_curr_task - set the current task for a given cpu.
  * @cpu: the processor in question.
@@ -8264,8 +8060,6 @@ void sched_move_task(struct task_struct *tsk)
 
         rq = task_rq_lock(tsk, &flags);
 
-        update_rq_clock(rq);
-
         running = task_current(rq, tsk);
         on_rq = tsk->se.on_rq;
 
@@ -8284,7 +8078,7 @@ void sched_move_task(struct task_struct *tsk)
         if (unlikely(running))
                 tsk->sched_class->set_curr_task(rq);
         if (on_rq)
-                enqueue_task(rq, tsk, 0, false);
+                enqueue_task(rq, tsk, 0);
 
         task_rq_unlock(rq, &flags);
 }
@@ -9098,43 +8892,32 @@ struct cgroup_subsys cpuacct_subsys = {
 
 #ifndef CONFIG_SMP
 
-int rcu_expedited_torture_stats(char *page)
-{
-        return 0;
-}
-EXPORT_SYMBOL_GPL(rcu_expedited_torture_stats);
-
 void synchronize_sched_expedited(void)
 {
+        barrier();
 }
 EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
 
 #else /* #ifndef CONFIG_SMP */
 
-static DEFINE_PER_CPU(struct migration_req, rcu_migration_req);
-static DEFINE_MUTEX(rcu_sched_expedited_mutex);
+static atomic_t synchronize_sched_expedited_count = ATOMIC_INIT(0);
 
-#define RCU_EXPEDITED_STATE_POST -2
-#define RCU_EXPEDITED_STATE_IDLE -1
-
-static int rcu_expedited_state = RCU_EXPEDITED_STATE_IDLE;
-
-int rcu_expedited_torture_stats(char *page)
+static int synchronize_sched_expedited_cpu_stop(void *data)
 {
-        int cnt = 0;
-        int cpu;
-
-        cnt += sprintf(&page[cnt], "state: %d /", rcu_expedited_state);
-        for_each_online_cpu(cpu) {
-                 cnt += sprintf(&page[cnt], " %d:%d",
-                                cpu, per_cpu(rcu_migration_req, cpu).dest_cpu);
-        }
-        cnt += sprintf(&page[cnt], "\n");
-        return cnt;
+        /*
+         * There must be a full memory barrier on each affected CPU
+         * between the time that try_stop_cpus() is called and the
+         * time that it returns.
+         *
+         * In the current initial implementation of cpu_stop, the
+         * above condition is already met when the control reaches
+         * this point and the following smp_mb() is not strictly
+         * necessary.  Do smp_mb() anyway for documentation and
+         * robustness against future implementation changes.
+         */
+        smp_mb(); /* See above comment block. */
+        return 0;
 }
-EXPORT_SYMBOL_GPL(rcu_expedited_torture_stats);
-
-static long synchronize_sched_expedited_count;
 
 /*
  * Wait for an rcu-sched grace period to elapse, but use "big hammer"
@@ -9148,18 +8931,14 @@ static long synchronize_sched_expedited_count;
  */
 void synchronize_sched_expedited(void)
 {
-        int cpu;
-        unsigned long flags;
-        bool need_full_sync = 0;
-        struct rq *rq;
-        struct migration_req *req;
-        long snap;
-        int trycount = 0;
+        int snap, trycount = 0;
 
         smp_mb();  /* ensure prior mod happens before capturing snap. */
-        snap = ACCESS_ONCE(synchronize_sched_expedited_count) + 1;
+        snap = atomic_read(&synchronize_sched_expedited_count) + 1;
         get_online_cpus();
-        while (!mutex_trylock(&rcu_sched_expedited_mutex)) {
+        while (try_stop_cpus(cpu_online_mask,
+                             synchronize_sched_expedited_cpu_stop,
+                             NULL) == -EAGAIN) {
                 put_online_cpus();
                 if (trycount++ < 10)
                         udelay(trycount * num_online_cpus());
@@ -9167,41 +8946,15 @@ void synchronize_sched_expedited(void)
                         synchronize_sched();
                         return;
                 }
-                if (ACCESS_ONCE(synchronize_sched_expedited_count) - snap > 0) {
+                if (atomic_read(&synchronize_sched_expedited_count) - snap > 0) {
                         smp_mb(); /* ensure test happens before caller kfree */
                         return;
                 }
                 get_online_cpus();
         }
-        rcu_expedited_state = RCU_EXPEDITED_STATE_POST;
-        for_each_online_cpu(cpu) {
-                rq = cpu_rq(cpu);
-                req = &per_cpu(rcu_migration_req, cpu);
-                init_completion(&req->done);
-                req->task = NULL;
-                req->dest_cpu = RCU_MIGRATION_NEED_QS;
-                raw_spin_lock_irqsave(&rq->lock, flags);
-                list_add(&req->list, &rq->migration_queue);
-                raw_spin_unlock_irqrestore(&rq->lock, flags);
-                wake_up_process(rq->migration_thread);
-        }
-        for_each_online_cpu(cpu) {
-                rcu_expedited_state = cpu;
-                req = &per_cpu(rcu_migration_req, cpu);
-                rq = cpu_rq(cpu);
-                wait_for_completion(&req->done);
-                raw_spin_lock_irqsave(&rq->lock, flags);
-                if (unlikely(req->dest_cpu == RCU_MIGRATION_MUST_SYNC))
-                        need_full_sync = 1;
-                req->dest_cpu = RCU_MIGRATION_IDLE;
-                raw_spin_unlock_irqrestore(&rq->lock, flags);
-        }
-        rcu_expedited_state = RCU_EXPEDITED_STATE_IDLE;
-        synchronize_sched_expedited_count++;
-        mutex_unlock(&rcu_sched_expedited_mutex);
+        atomic_inc(&synchronize_sched_expedited_count);
+        smp_mb__after_atomic_inc(); /* ensure post-GP actions seen after GP. */
         put_online_cpus();
-        if (need_full_sync)
-                synchronize_sched();
 }
 EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
 
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index 5b496132c28a..906a0f718cb3 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -41,6 +41,7 @@ unsigned long long __attribute__((weak)) sched_clock(void)
         return (unsigned long long)(jiffies - INITIAL_JIFFIES)
                                         * (NSEC_PER_SEC / HZ);
 }
+EXPORT_SYMBOL_GPL(sched_clock);
 
 static __read_mostly int sched_clock_running;
 
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 19be00ba6123..35565395d00d 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -70,16 +70,16 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu,
         PN(se->vruntime);
         PN(se->sum_exec_runtime);
 #ifdef CONFIG_SCHEDSTATS
-        PN(se->wait_start);
-        PN(se->sleep_start);
-        PN(se->block_start);
-        PN(se->sleep_max);
-        PN(se->block_max);
-        PN(se->exec_max);
-        PN(se->slice_max);
-        PN(se->wait_max);
-        PN(se->wait_sum);
-        P(se->wait_count);
+        PN(se->statistics.wait_start);
+        PN(se->statistics.sleep_start);
+        PN(se->statistics.block_start);
+        PN(se->statistics.sleep_max);
+        PN(se->statistics.block_max);
+        PN(se->statistics.exec_max);
+        PN(se->statistics.slice_max);
+        PN(se->statistics.wait_max);
+        PN(se->statistics.wait_sum);
+        P(se->statistics.wait_count);
 #endif
         P(se->load.weight);
 #undef PN
@@ -104,7 +104,7 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
         SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
                 SPLIT_NS(p->se.vruntime),
                 SPLIT_NS(p->se.sum_exec_runtime),
-                SPLIT_NS(p->se.sum_sleep_runtime));
+                SPLIT_NS(p->se.statistics.sum_sleep_runtime));
 #else
         SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld",
                 0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
@@ -175,11 +175,6 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
         task_group_path(tg, path, sizeof(path));
 
         SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
-#elif defined(CONFIG_USER_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
-        {
-                uid_t uid = cfs_rq->tg->uid;
-                SEQ_printf(m, "\ncfs_rq[%d] for UID: %u\n", cpu, uid);
-        }
 #else
         SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
 #endif
@@ -386,15 +381,9 @@ __initcall(init_sched_debug_procfs);
 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 {
         unsigned long nr_switches;
-        unsigned long flags;
-        int num_threads = 1;
-
-        if (lock_task_sighand(p, &flags)) {
-                num_threads = atomic_read(&p->signal->count);
-                unlock_task_sighand(p, &flags);
-        }
 
-        SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
+        SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid,
+                                                get_nr_threads(p));
         SEQ_printf(m,
                 "---------------------------------------------------------\n");
 #define __P(F) \
@@ -409,40 +398,38 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
         PN(se.exec_start);
         PN(se.vruntime);
         PN(se.sum_exec_runtime);
-        PN(se.avg_overlap);
-        PN(se.avg_wakeup);
 
         nr_switches = p->nvcsw + p->nivcsw;
 
 #ifdef CONFIG_SCHEDSTATS
-        PN(se.wait_start);
-        PN(se.sleep_start);
-        PN(se.block_start);
-        PN(se.sleep_max);
-        PN(se.block_max);
-        PN(se.exec_max);
-        PN(se.slice_max);
-        PN(se.wait_max);
-        PN(se.wait_sum);
-        P(se.wait_count);
-        PN(se.iowait_sum);
-        P(se.iowait_count);
+        PN(se.statistics.wait_start);
+        PN(se.statistics.sleep_start);
+        PN(se.statistics.block_start);
+        PN(se.statistics.sleep_max);
+        PN(se.statistics.block_max);
+        PN(se.statistics.exec_max);
+        PN(se.statistics.slice_max);
+        PN(se.statistics.wait_max);
+        PN(se.statistics.wait_sum);
+        P(se.statistics.wait_count);
+        PN(se.statistics.iowait_sum);
+        P(se.statistics.iowait_count);
         P(sched_info.bkl_count);
         P(se.nr_migrations);
-        P(se.nr_migrations_cold);
-        P(se.nr_failed_migrations_affine);
-        P(se.nr_failed_migrations_running);
-        P(se.nr_failed_migrations_hot);
-        P(se.nr_forced_migrations);
-        P(se.nr_wakeups);
-        P(se.nr_wakeups_sync);
-        P(se.nr_wakeups_migrate);
-        P(se.nr_wakeups_local);
-        P(se.nr_wakeups_remote);
-        P(se.nr_wakeups_affine);
-        P(se.nr_wakeups_affine_attempts);
-        P(se.nr_wakeups_passive);
-        P(se.nr_wakeups_idle);
+        P(se.statistics.nr_migrations_cold);
+        P(se.statistics.nr_failed_migrations_affine);
+        P(se.statistics.nr_failed_migrations_running);
+        P(se.statistics.nr_failed_migrations_hot);
+        P(se.statistics.nr_forced_migrations);
+        P(se.statistics.nr_wakeups);
+        P(se.statistics.nr_wakeups_sync);
+        P(se.statistics.nr_wakeups_migrate);
+        P(se.statistics.nr_wakeups_local);
+        P(se.statistics.nr_wakeups_remote);
+        P(se.statistics.nr_wakeups_affine);
+        P(se.statistics.nr_wakeups_affine_attempts);
+        P(se.statistics.nr_wakeups_passive);
+        P(se.statistics.nr_wakeups_idle);
 
         {
                 u64 avg_atom, avg_per_cpu;
@@ -493,31 +480,6 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 void proc_sched_set_task(struct task_struct *p)
 {
 #ifdef CONFIG_SCHEDSTATS
-        p->se.wait_max                          = 0;
-        p->se.wait_sum                          = 0;
-        p->se.wait_count                        = 0;
-        p->se.iowait_sum                        = 0;
-        p->se.iowait_count                      = 0;
-        p->se.sleep_max                         = 0;
-        p->se.sum_sleep_runtime                 = 0;
-        p->se.block_max                         = 0;
-        p->se.exec_max                          = 0;
-        p->se.slice_max                         = 0;
-        p->se.nr_migrations                     = 0;
-        p->se.nr_migrations_cold                = 0;
-        p->se.nr_failed_migrations_affine       = 0;
-        p->se.nr_failed_migrations_running      = 0;
-        p->se.nr_failed_migrations_hot          = 0;
-        p->se.nr_forced_migrations              = 0;
-        p->se.nr_wakeups                        = 0;
-        p->se.nr_wakeups_sync                   = 0;
-        p->se.nr_wakeups_migrate                = 0;
-        p->se.nr_wakeups_local                  = 0;
-        p->se.nr_wakeups_remote                 = 0;
-        p->se.nr_wakeups_affine                 = 0;
-        p->se.nr_wakeups_affine_attempts        = 0;
-        p->se.nr_wakeups_passive                = 0;
-        p->se.nr_wakeups_idle                   = 0;
-        p->sched_info.bkl_count                 = 0;
+        memset(&p->se.statistics, 0, sizeof(p->se.statistics));
 #endif
 }
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 5a5ea2cd924f..217e4a9393e4 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -35,8 +35,8 @@
  * (to see the precise effective timeslice length of your workload,
  *  run vmstat and monitor the context-switches (cs) field)
  */
-unsigned int sysctl_sched_latency = 5000000ULL;
-unsigned int normalized_sysctl_sched_latency = 5000000ULL;
+unsigned int sysctl_sched_latency = 6000000ULL;
+unsigned int normalized_sysctl_sched_latency = 6000000ULL;
 
 /*
  * The initial- and re-scaling of tunables is configurable
@@ -52,15 +52,15 @@ enum sched_tunable_scaling sysctl_sched_tunable_scaling
 
 /*
  * Minimal preemption granularity for CPU-bound tasks:
- * (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ * (default: 2 msec * (1 + ilog(ncpus)), units: nanoseconds)
  */
-unsigned int sysctl_sched_min_granularity = 1000000ULL;
-unsigned int normalized_sysctl_sched_min_granularity = 1000000ULL;
+unsigned int sysctl_sched_min_granularity = 2000000ULL;
+unsigned int normalized_sysctl_sched_min_granularity = 2000000ULL;
 
 /*
  * is kept at sysctl_sched_latency / sysctl_sched_min_granularity
  */
-static unsigned int sched_nr_latency = 5;
+static unsigned int sched_nr_latency = 3;
 
 /*
  * After fork, child runs first. If set to 0 (default) then
@@ -505,7 +505,8 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
 {
         unsigned long delta_exec_weighted;
 
-        schedstat_set(curr->exec_max, max((u64)delta_exec, curr->exec_max));
+        schedstat_set(curr->statistics.exec_max,
+                      max((u64)delta_exec, curr->statistics.exec_max));
 
         curr->sum_exec_runtime += delta_exec;
         schedstat_add(cfs_rq, exec_clock, delta_exec);
@@ -548,7 +549,7 @@ static void update_curr(struct cfs_rq *cfs_rq)
 static inline void
 update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-        schedstat_set(se->wait_start, rq_of(cfs_rq)->clock);
+        schedstat_set(se->statistics.wait_start, rq_of(cfs_rq)->clock);
 }
 
 /*
@@ -567,18 +568,18 @@ static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
 static void
 update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-        schedstat_set(se->wait_max, max(se->wait_max,
-                        rq_of(cfs_rq)->clock - se->wait_start));
-        schedstat_set(se->wait_count, se->wait_count + 1);
-        schedstat_set(se->wait_sum, se->wait_sum +
-                        rq_of(cfs_rq)->clock - se->wait_start);
+        schedstat_set(se->statistics.wait_max, max(se->statistics.wait_max,
+                        rq_of(cfs_rq)->clock - se->statistics.wait_start));
+        schedstat_set(se->statistics.wait_count, se->statistics.wait_count + 1);
+        schedstat_set(se->statistics.wait_sum, se->statistics.wait_sum +
+                        rq_of(cfs_rq)->clock - se->statistics.wait_start);
 #ifdef CONFIG_SCHEDSTATS
         if (entity_is_task(se)) {
                 trace_sched_stat_wait(task_of(se),
-                        rq_of(cfs_rq)->clock - se->wait_start);
+                        rq_of(cfs_rq)->clock - se->statistics.wait_start);
         }
 #endif
-        schedstat_set(se->wait_start, 0);
+        schedstat_set(se->statistics.wait_start, 0);
 }
 
 static inline void
@@ -657,39 +658,39 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
         if (entity_is_task(se))
                 tsk = task_of(se);
 
-        if (se->sleep_start) {
-                u64 delta = rq_of(cfs_rq)->clock - se->sleep_start;
+        if (se->statistics.sleep_start) {
+                u64 delta = rq_of(cfs_rq)->clock - se->statistics.sleep_start;
 
                 if ((s64)delta < 0)
                         delta = 0;
 
-                if (unlikely(delta > se->sleep_max))
-                        se->sleep_max = delta;
+                if (unlikely(delta > se->statistics.sleep_max))
+                        se->statistics.sleep_max = delta;
 
-                se->sleep_start = 0;
-                se->sum_sleep_runtime += delta;
+                se->statistics.sleep_start = 0;
+                se->statistics.sum_sleep_runtime += delta;
 
                 if (tsk) {
                         account_scheduler_latency(tsk, delta >> 10, 1);
                         trace_sched_stat_sleep(tsk, delta);
                 }
         }
-        if (se->block_start) {
-                u64 delta = rq_of(cfs_rq)->clock - se->block_start;
+        if (se->statistics.block_start) {
+                u64 delta = rq_of(cfs_rq)->clock - se->statistics.block_start;
 
                 if ((s64)delta < 0)
                         delta = 0;
 
-                if (unlikely(delta > se->block_max))
-                        se->block_max = delta;
+                if (unlikely(delta > se->statistics.block_max))
+                        se->statistics.block_max = delta;
 
-                se->block_start = 0;
-                se->sum_sleep_runtime += delta;
+                se->statistics.block_start = 0;
+                se->statistics.sum_sleep_runtime += delta;
 
                 if (tsk) {
                         if (tsk->in_iowait) {
-                                se->iowait_sum += delta;
-                                se->iowait_count++;
+                                se->statistics.iowait_sum += delta;
+                                se->statistics.iowait_count++;
                                 trace_sched_stat_iowait(tsk, delta);
                         }
 
@@ -737,20 +738,10 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
                 vruntime += sched_vslice(cfs_rq, se);
 
         /* sleeps up to a single latency don't count. */
-        if (!initial && sched_feat(FAIR_SLEEPERS)) {
+        if (!initial) {
                 unsigned long thresh = sysctl_sched_latency;
 
                 /*
-                 * Convert the sleeper threshold into virtual time.
-                 * SCHED_IDLE is a special sub-class.  We care about
-                 * fairness only relative to other SCHED_IDLE tasks,
-                 * all of which have the same weight.
-                 */
-                if (sched_feat(NORMALIZED_SLEEPER) && (!entity_is_task(se) ||
-                                 task_of(se)->policy != SCHED_IDLE))
-                        thresh = calc_delta_fair(thresh, se);
-
-                /*
                  * Halve their sleep time's effect, to allow
                  * for a gentler effect of sleepers:
                  */
@@ -766,9 +757,6 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
         se->vruntime = vruntime;
 }
 
-#define ENQUEUE_WAKEUP  1
-#define ENQUEUE_MIGRATE 2
-
 static void
 enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 {
@@ -776,7 +764,7 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
          * Update the normalized vruntime before updating min_vruntime
          * through callig update_curr().
          */
-        if (!(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_MIGRATE))
+        if (!(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_WAKING))
                 se->vruntime += cfs_rq->min_vruntime;
 
         /*
@@ -812,7 +800,7 @@ static void clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se)
 }
 
 static void
-dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
+dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 {
         /*
          * Update run-time statistics of the 'current'.
@@ -820,15 +808,15 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
         update_curr(cfs_rq);
 
         update_stats_dequeue(cfs_rq, se);
-        if (sleep) {
+        if (flags & DEQUEUE_SLEEP) {
 #ifdef CONFIG_SCHEDSTATS
                 if (entity_is_task(se)) {
                         struct task_struct *tsk = task_of(se);
 
                         if (tsk->state & TASK_INTERRUPTIBLE)
-                                se->sleep_start = rq_of(cfs_rq)->clock;
+                                se->statistics.sleep_start = rq_of(cfs_rq)->clock;
                         if (tsk->state & TASK_UNINTERRUPTIBLE)
-                                se->block_start = rq_of(cfs_rq)->clock;
+                                se->statistics.block_start = rq_of(cfs_rq)->clock;
                 }
 #endif
         }
@@ -845,7 +833,7 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
          * update can refer to the ->curr item and we need to reflect this
          * movement in our normalized position.
          */
-        if (!sleep)
+        if (!(flags & DEQUEUE_SLEEP))
                 se->vruntime -= cfs_rq->min_vruntime;
 }
 
@@ -912,7 +900,7 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
          * when there are only lesser-weight tasks around):
          */
         if (rq_of(cfs_rq)->load.weight >= 2*se->load.weight) {
-                se->slice_max = max(se->slice_max,
+                se->statistics.slice_max = max(se->statistics.slice_max,
                         se->sum_exec_runtime - se->prev_sum_exec_runtime);
         }
 #endif
@@ -1054,16 +1042,10 @@ static inline void hrtick_update(struct rq *rq)
  * then put the task into the rbtree:
  */
 static void
-enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup, bool head)
+enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 {
         struct cfs_rq *cfs_rq;
         struct sched_entity *se = &p->se;
-        int flags = 0;
-
-        if (wakeup)
-                flags |= ENQUEUE_WAKEUP;
-        if (p->state == TASK_WAKING)
-                flags |= ENQUEUE_MIGRATE;
 
         for_each_sched_entity(se) {
                 if (se->on_rq)
@@ -1081,18 +1063,18 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup, bool head)
  * decreased. We remove the task from the rbtree and
  * update the fair scheduling stats:
  */
-static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int sleep)
+static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 {
         struct cfs_rq *cfs_rq;
         struct sched_entity *se = &p->se;
 
         for_each_sched_entity(se) {
                 cfs_rq = cfs_rq_of(se);
-                dequeue_entity(cfs_rq, se, sleep);
+                dequeue_entity(cfs_rq, se, flags);
                 /* Don't dequeue parent if it has other entities besides us */
                 if (cfs_rq->load.weight)
                         break;
-                sleep = 1;
+                flags |= DEQUEUE_SLEEP;
         }
 
         hrtick_update(rq);
@@ -1240,7 +1222,6 @@ static inline unsigned long effective_load(struct task_group *tg, int cpu,
 
 static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
 {
-        struct task_struct *curr = current;
         unsigned long this_load, load;
         int idx, this_cpu, prev_cpu;
         unsigned long tl_per_task;
@@ -1255,18 +1236,6 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
         load      = source_load(prev_cpu, idx);
         this_load = target_load(this_cpu, idx);
 
-        if (sync) {
-               if (sched_feat(SYNC_LESS) &&
-                   (curr->se.avg_overlap > sysctl_sched_migration_cost ||
-                    p->se.avg_overlap > sysctl_sched_migration_cost))
-                       sync = 0;
-        } else {
-                if (sched_feat(SYNC_MORE) &&
-                    (curr->se.avg_overlap < sysctl_sched_migration_cost &&
-                     p->se.avg_overlap < sysctl_sched_migration_cost))
-                        sync = 1;
-        }
-
         /*
          * If sync wakeup then subtract the (maximum possible)
          * effect of the currently running task from the load
@@ -1306,7 +1275,7 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
         if (sync && balanced)
                 return 1;
 
-        schedstat_inc(p, se.nr_wakeups_affine_attempts);
+        schedstat_inc(p, se.statistics.nr_wakeups_affine_attempts);
         tl_per_task = cpu_avg_load_per_task(this_cpu);
 
         if (balanced ||
@@ -1318,7 +1287,7 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
                  * there is no bad imbalance.
                  */
                 schedstat_inc(sd, ttwu_move_affine);
-                schedstat_inc(p, se.nr_wakeups_affine);
+                schedstat_inc(p, se.statistics.nr_wakeups_affine);
 
                 return 1;
         }
@@ -1406,29 +1375,48 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
 /*
  * Try and locate an idle CPU in the sched_domain.
  */
-static int
-select_idle_sibling(struct task_struct *p, struct sched_domain *sd, int target)
+static int select_idle_sibling(struct task_struct *p, int target)
 {
         int cpu = smp_processor_id();
         int prev_cpu = task_cpu(p);
+        struct sched_domain *sd;
         int i;
 
         /*
-         * If this domain spans both cpu and prev_cpu (see the SD_WAKE_AFFINE
-         * test in select_task_rq_fair) and the prev_cpu is idle then that's
-         * always a better target than the current cpu.
+         * If the task is going to be woken-up on this cpu and if it is
+         * already idle, then it is the right target.
          */
-        if (target == cpu && !cpu_rq(prev_cpu)->cfs.nr_running)
+        if (target == cpu && idle_cpu(cpu))
+                return cpu;
+
+        /*
+         * If the task is going to be woken-up on the cpu where it previously
+         * ran and if it is currently idle, then it the right target.
+         */
+        if (target == prev_cpu && idle_cpu(prev_cpu))
                 return prev_cpu;
 
         /*
-         * Otherwise, iterate the domain and find an elegible idle cpu.
+         * Otherwise, iterate the domains and find an elegible idle cpu.
          */
-        for_each_cpu_and(i, sched_domain_span(sd), &p->cpus_allowed) {
-                if (!cpu_rq(i)->cfs.nr_running) {
-                        target = i;
+        for_each_domain(target, sd) {
+                if (!(sd->flags & SD_SHARE_PKG_RESOURCES))
                         break;
+
+                for_each_cpu_and(i, sched_domain_span(sd), &p->cpus_allowed) {
+                        if (idle_cpu(i)) {
+                                target = i;
+                                break;
+                        }
                 }
+
+                /*
+                 * Lets stop looking for an idle sibling when we reached
+                 * the domain that spans the current cpu and prev_cpu.
+                 */
+                if (cpumask_test_cpu(cpu, sched_domain_span(sd)) &&
+                    cpumask_test_cpu(prev_cpu, sched_domain_span(sd)))
+                        break;
         }
 
         return target;
@@ -1445,7 +1433,8 @@ select_idle_sibling(struct task_struct *p, struct sched_domain *sd, int target)
  *
  * preempt must be disabled.
  */
-static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
+static int
+select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_flags)
 {
         struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL;
         int cpu = smp_processor_id();
@@ -1456,8 +1445,7 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
         int sync = wake_flags & WF_SYNC;
 
         if (sd_flag & SD_BALANCE_WAKE) {
-                if (sched_feat(AFFINE_WAKEUPS) &&
-                    cpumask_test_cpu(cpu, &p->cpus_allowed))
+                if (cpumask_test_cpu(cpu, &p->cpus_allowed))
                         want_affine = 1;
                 new_cpu = prev_cpu;
         }
@@ -1491,34 +1479,13 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
                 }
 
                 /*
-                 * While iterating the domains looking for a spanning
-                 * WAKE_AFFINE domain, adjust the affine target to any idle cpu
-                 * in cache sharing domains along the way.
+                 * If both cpu and prev_cpu are part of this domain,
+                 * cpu is a valid SD_WAKE_AFFINE target.
                  */
-                if (want_affine) {
-                        int target = -1;
-
-                        /*
-                         * If both cpu and prev_cpu are part of this domain,
-                         * cpu is a valid SD_WAKE_AFFINE target.
-                         */
-                        if (cpumask_test_cpu(prev_cpu, sched_domain_span(tmp)))
-                                target = cpu;
-
-                        /*
-                         * If there's an idle sibling in this domain, make that
-                         * the wake_affine target instead of the current cpu.
-                         */
-                        if (tmp->flags & SD_SHARE_PKG_RESOURCES)
-                                target = select_idle_sibling(p, tmp, target);
-
-                        if (target >= 0) {
-                                if (tmp->flags & SD_WAKE_AFFINE) {
-                                        affine_sd = tmp;
-                                        want_affine = 0;
-                                }
-                                cpu = target;
-                        }
+                if (want_affine && (tmp->flags & SD_WAKE_AFFINE) &&
+                    cpumask_test_cpu(prev_cpu, sched_domain_span(tmp))) {
+                        affine_sd = tmp;
+                        want_affine = 0;
                 }
 
                 if (!want_sd && !want_affine)
@@ -1531,22 +1498,29 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
                         sd = tmp;
         }
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
         if (sched_feat(LB_SHARES_UPDATE)) {
                 /*
                  * Pick the largest domain to update shares over
                  */
                 tmp = sd;
-                if (affine_sd && (!tmp ||
-                                  cpumask_weight(sched_domain_span(affine_sd)) >
-                                  cpumask_weight(sched_domain_span(sd))))
+                if (affine_sd && (!tmp || affine_sd->span_weight > sd->span_weight))
                         tmp = affine_sd;
 
-                if (tmp)
+                if (tmp) {
+                        raw_spin_unlock(&rq->lock);
                         update_shares(tmp);
+                        raw_spin_lock(&rq->lock);
+                }
         }
+#endif
 
-        if (affine_sd && wake_affine(affine_sd, p, sync))
-                return cpu;
+        if (affine_sd) {
+                if (cpu == prev_cpu || wake_affine(affine_sd, p, sync))
+                        return select_idle_sibling(p, cpu);
+                else
+                        return select_idle_sibling(p, prev_cpu);
+        }
 
         while (sd) {
                 int load_idx = sd->forkexec_idx;
@@ -1576,10 +1550,10 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
 
                 /* Now try balancing at a lower domain level of new_cpu */
                 cpu = new_cpu;
-                weight = cpumask_weight(sched_domain_span(sd));
+                weight = sd->span_weight;
                 sd = NULL;
                 for_each_domain(cpu, tmp) {
-                        if (weight <= cpumask_weight(sched_domain_span(tmp)))
+                        if (weight <= tmp->span_weight)
                                 break;
                         if (tmp->flags & sd_flag)
                                 sd = tmp;
@@ -1591,63 +1565,26 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
 }
 #endif /* CONFIG_SMP */
 
-/*
- * Adaptive granularity
- *
- * se->avg_wakeup gives the average time a task runs until it does a wakeup,
- * with the limit of wakeup_gran -- when it never does a wakeup.
- *
- * So the smaller avg_wakeup is the faster we want this task to preempt,
- * but we don't want to treat the preemptee unfairly and therefore allow it
- * to run for at least the amount of time we'd like to run.
- *
- * NOTE: we use 2*avg_wakeup to increase the probability of actually doing one
- *
- * NOTE: we use *nr_running to scale with load, this nicely matches the
- *       degrading latency on load.
- */
-static unsigned long
-adaptive_gran(struct sched_entity *curr, struct sched_entity *se)
-{
-        u64 this_run = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;
-        u64 expected_wakeup = 2*se->avg_wakeup * cfs_rq_of(se)->nr_running;
-        u64 gran = 0;
-
-        if (this_run < expected_wakeup)
-                gran = expected_wakeup - this_run;
-
-        return min_t(s64, gran, sysctl_sched_wakeup_granularity);
-}
-
 static unsigned long
 wakeup_gran(struct sched_entity *curr, struct sched_entity *se)
 {
         unsigned long gran = sysctl_sched_wakeup_granularity;
 
-        if (cfs_rq_of(curr)->curr && sched_feat(ADAPTIVE_GRAN))
-                gran = adaptive_gran(curr, se);
-
         /*
          * Since its curr running now, convert the gran from real-time
          * to virtual-time in his units.
+         *
+         * By using 'se' instead of 'curr' we penalize light tasks, so
+         * they get preempted easier. That is, if 'se' < 'curr' then
+         * the resulting gran will be larger, therefore penalizing the
+         * lighter, if otoh 'se' > 'curr' then the resulting gran will
+         * be smaller, again penalizing the lighter task.
+         *
+         * This is especially important for buddies when the leftmost
+         * task is higher priority than the buddy.
          */
-        if (sched_feat(ASYM_GRAN)) {
-                /*
-                 * By using 'se' instead of 'curr' we penalize light tasks, so
-                 * they get preempted easier. That is, if 'se' < 'curr' then
-                 * the resulting gran will be larger, therefore penalizing the
-                 * lighter, if otoh 'se' > 'curr' then the resulting gran will
-                 * be smaller, again penalizing the lighter task.
-                 *
-                 * This is especially important for buddies when the leftmost
-                 * task is higher priority than the buddy.
-                 */
-                if (unlikely(se->load.weight != NICE_0_LOAD))
-                        gran = calc_delta_fair(gran, se);
-        } else {
-                if (unlikely(curr->load.weight != NICE_0_LOAD))
-                        gran = calc_delta_fair(gran, curr);
-        }
+        if (unlikely(se->load.weight != NICE_0_LOAD))
+                gran = calc_delta_fair(gran, se);
 
         return gran;
 }
@@ -1705,7 +1642,6 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
         struct task_struct *curr = rq->curr;
         struct sched_entity *se = &curr->se, *pse = &p->se;
         struct cfs_rq *cfs_rq = task_cfs_rq(curr);
-        int sync = wake_flags & WF_SYNC;
         int scale = cfs_rq->nr_running >= sched_nr_latency;
 
         if (unlikely(rt_prio(p->prio)))
@@ -1738,14 +1674,6 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
         if (unlikely(curr->policy == SCHED_IDLE))
                 goto preempt;
 
-        if (sched_feat(WAKEUP_SYNC) && sync)
-                goto preempt;
-
-        if (sched_feat(WAKEUP_OVERLAP) &&
-                        se->avg_overlap < sysctl_sched_migration_cost &&
-                        pse->avg_overlap < sysctl_sched_migration_cost)
-                goto preempt;
-
         if (!sched_feat(WAKEUP_PREEMPT))
                 return;
 
@@ -1844,13 +1772,13 @@ int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu,
          * 3) are cache-hot on their current CPU.
          */
         if (!cpumask_test_cpu(this_cpu, &p->cpus_allowed)) {
-                schedstat_inc(p, se.nr_failed_migrations_affine);
+                schedstat_inc(p, se.statistics.nr_failed_migrations_affine);
                 return 0;
         }
         *all_pinned = 0;
 
         if (task_running(rq, p)) {
-                schedstat_inc(p, se.nr_failed_migrations_running);
+                schedstat_inc(p, se.statistics.nr_failed_migrations_running);
                 return 0;
         }
 
@@ -1866,14 +1794,14 @@ int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu,
 #ifdef CONFIG_SCHEDSTATS
                 if (tsk_cache_hot) {
                         schedstat_inc(sd, lb_hot_gained[idle]);
-                        schedstat_inc(p, se.nr_forced_migrations);
+                        schedstat_inc(p, se.statistics.nr_forced_migrations);
                 }
 #endif
                 return 1;
         }
 
         if (tsk_cache_hot) {
-                schedstat_inc(p, se.nr_failed_migrations_hot);
+                schedstat_inc(p, se.statistics.nr_failed_migrations_hot);
                 return 0;
         }
         return 1;
@@ -2311,7 +2239,7 @@ unsigned long __weak arch_scale_freq_power(struct sched_domain *sd, int cpu)
 
 unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu)
 {
-        unsigned long weight = cpumask_weight(sched_domain_span(sd));
+        unsigned long weight = sd->span_weight;
         unsigned long smt_gain = sd->smt_gain;
 
         smt_gain /= weight;
@@ -2344,7 +2272,7 @@ unsigned long scale_rt_power(int cpu)
 
 static void update_cpu_power(struct sched_domain *sd, int cpu)
 {
-        unsigned long weight = cpumask_weight(sched_domain_span(sd));
+        unsigned long weight = sd->span_weight;
         unsigned long power = SCHED_LOAD_SCALE;
         struct sched_group *sdg = sd->groups;
 
@@ -2870,6 +2798,8 @@ static int need_active_balance(struct sched_domain *sd, int sd_idle, int idle)
         return unlikely(sd->nr_balance_failed > sd->cache_nice_tries+2);
 }
 
+static int active_load_balance_cpu_stop(void *data);
+
 /*
  * Check this_cpu to ensure it is balanced within domain. Attempt to move
  * tasks if there is an imbalance.
@@ -2959,8 +2889,9 @@ redo:
                 if (need_active_balance(sd, sd_idle, idle)) {
                         raw_spin_lock_irqsave(&busiest->lock, flags);
 
-                        /* don't kick the migration_thread, if the curr
-                         * task on busiest cpu can't be moved to this_cpu
+                        /* don't kick the active_load_balance_cpu_stop,
+                         * if the curr task on busiest cpu can't be
+                         * moved to this_cpu
                          */
                         if (!cpumask_test_cpu(this_cpu,
                                               &busiest->curr->cpus_allowed)) {
@@ -2970,14 +2901,22 @@ redo:
                                 goto out_one_pinned;
                         }
 
+                        /*
+                         * ->active_balance synchronizes accesses to
+                         * ->active_balance_work.  Once set, it's cleared
+                         * only after active load balance is finished.
+                         */
                         if (!busiest->active_balance) {
                                 busiest->active_balance = 1;
                                 busiest->push_cpu = this_cpu;
                                 active_balance = 1;
                         }
                         raw_spin_unlock_irqrestore(&busiest->lock, flags);
+
                         if (active_balance)
-                                wake_up_process(busiest->migration_thread);
+                                stop_one_cpu_nowait(cpu_of(busiest),
+                                        active_load_balance_cpu_stop, busiest,
+                                        &busiest->active_balance_work);
 
                         /*
                          * We've kicked active balancing, reset the failure
@@ -3084,24 +3023,29 @@ static void idle_balance(int this_cpu, struct rq *this_rq)
 }
 
 /*
- * active_load_balance is run by migration threads. It pushes running tasks
- * off the busiest CPU onto idle CPUs. It requires at least 1 task to be
- * running on each physical CPU where possible, and avoids physical /
- * logical imbalances.
- *
- * Called with busiest_rq locked.
+ * active_load_balance_cpu_stop is run by cpu stopper. It pushes
+ * running tasks off the busiest CPU onto idle CPUs. It requires at
+ * least 1 task to be running on each physical CPU where possible, and
+ * avoids physical / logical imbalances.
  */
-static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
+static int active_load_balance_cpu_stop(void *data)
 {
+        struct rq *busiest_rq = data;
+        int busiest_cpu = cpu_of(busiest_rq);
         int target_cpu = busiest_rq->push_cpu;
+        struct rq *target_rq = cpu_rq(target_cpu);
         struct sched_domain *sd;
-        struct rq *target_rq;
+
+        raw_spin_lock_irq(&busiest_rq->lock);
+
+        /* make sure the requested cpu hasn't gone down in the meantime */
+        if (unlikely(busiest_cpu != smp_processor_id() ||
+                     !busiest_rq->active_balance))
+                goto out_unlock;
 
         /* Is there any task to move? */
         if (busiest_rq->nr_running <= 1)
-                return;
-
-        target_rq = cpu_rq(target_cpu);
+                goto out_unlock;
 
         /*
          * This condition is "impossible", if it occurs
@@ -3112,8 +3056,6 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
 
         /* move a task from busiest_rq to target_rq */
         double_lock_balance(busiest_rq, target_rq);
-        update_rq_clock(busiest_rq);
-        update_rq_clock(target_rq);
 
         /* Search for an sd spanning us and the target CPU. */
         for_each_domain(target_cpu, sd) {
@@ -3132,6 +3074,10 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
                         schedstat_inc(sd, alb_failed);
         }
         double_unlock_balance(busiest_rq, target_rq);
+out_unlock:
+        busiest_rq->active_balance = 0;
+        raw_spin_unlock_irq(&busiest_rq->lock);
+        return 0;
 }
 
 #ifdef CONFIG_NO_HZ
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index d5059fd761d9..83c66e8ad3ee 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -1,11 +1,4 @@
 /*
- * Disregards a certain amount of sleep time (sched_latency_ns) and
- * considers the task to be running during that period. This gives it
- * a service deficit on wakeup, allowing it to run sooner.
- */
-SCHED_FEAT(FAIR_SLEEPERS, 1)
-
-/*
  * Only give sleepers 50% of their service deficit. This allows
  * them to run sooner, but does not allow tons of sleepers to
  * rip the spread apart.
@@ -13,13 +6,6 @@ SCHED_FEAT(FAIR_SLEEPERS, 1)
 SCHED_FEAT(GENTLE_FAIR_SLEEPERS, 1)
 
 /*
- * By not normalizing the sleep time, heavy tasks get an effective
- * longer period, and lighter task an effective shorter period they
- * are considered running.
- */
-SCHED_FEAT(NORMALIZED_SLEEPER, 0)
-
-/*
  * Place new tasks ahead so that they do not starve already running
  * tasks
  */
@@ -31,37 +17,6 @@ SCHED_FEAT(START_DEBIT, 1)
 SCHED_FEAT(WAKEUP_PREEMPT, 1)
 
 /*
- * Compute wakeup_gran based on task behaviour, clipped to
- *  [0, sched_wakeup_gran_ns]
- */
-SCHED_FEAT(ADAPTIVE_GRAN, 1)
-
-/*
- * When converting the wakeup granularity to virtual time, do it such
- * that heavier tasks preempting a lighter task have an edge.
- */
-SCHED_FEAT(ASYM_GRAN, 1)
-
-/*
- * Always wakeup-preempt SYNC wakeups, see SYNC_WAKEUPS.
- */
-SCHED_FEAT(WAKEUP_SYNC, 0)
-
-/*
- * Wakeup preempt based on task behaviour. Tasks that do not overlap
- * don't get preempted.
- */
-SCHED_FEAT(WAKEUP_OVERLAP, 0)
-
-/*
- * Use the SYNC wakeup hint, pipes and the likes use this to indicate
- * the remote end is likely to consume the data we just wrote, and
- * therefore has cache benefit from being placed on the same cpu, see
- * also AFFINE_WAKEUPS.
- */
-SCHED_FEAT(SYNC_WAKEUPS, 1)
-
-/*
  * Based on load and program behaviour, see if it makes sense to place
  * a newly woken task on the same cpu as the task that woke it --
  * improve cache locality. Typically used with SYNC wakeups as
@@ -70,16 +25,6 @@ SCHED_FEAT(SYNC_WAKEUPS, 1)
 SCHED_FEAT(AFFINE_WAKEUPS, 1)
 
 /*
- * Weaken SYNC hint based on overlap
- */
-SCHED_FEAT(SYNC_LESS, 1)
-
-/*
- * Add SYNC hint based on overlap
- */
-SCHED_FEAT(SYNC_MORE, 0)
-
-/*
  * Prefer to schedule the task we woke last (assuming it failed
  * wakeup-preemption), since its likely going to consume data we
  * touched, increases cache locality.
diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c
index a8a6d8a50947..9fa0f402c87c 100644
--- a/kernel/sched_idletask.c
+++ b/kernel/sched_idletask.c
@@ -6,7 +6,8 @@
  */
 
 #ifdef CONFIG_SMP
-static int select_task_rq_idle(struct task_struct *p, int sd_flag, int flags)
+static int
+select_task_rq_idle(struct rq *rq, struct task_struct *p, int sd_flag, int flags)
 {
         return task_cpu(p); /* IDLE tasks as never migrated */
 }
@@ -22,8 +23,7 @@ static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int fl
 static struct task_struct *pick_next_task_idle(struct rq *rq)
 {
         schedstat_inc(rq, sched_goidle);
-        /* adjust the active tasks as we might go into a long sleep */
-        calc_load_account_active(rq);
+        calc_load_account_idle(rq);
         return rq->idle;
 }
 
@@ -32,7 +32,7 @@ static struct task_struct *pick_next_task_idle(struct rq *rq)
  * message if some code attempts to do it:
  */
 static void
-dequeue_task_idle(struct rq *rq, struct task_struct *p, int sleep)
+dequeue_task_idle(struct rq *rq, struct task_struct *p, int flags)
 {
         raw_spin_unlock_irq(&rq->lock);
         printk(KERN_ERR "bad: scheduling from the idle thread!\n");
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index b5b920ae2ea7..8afb953e31c6 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -613,7 +613,7 @@ static void update_curr_rt(struct rq *rq)
         if (unlikely((s64)delta_exec < 0))
                 delta_exec = 0;
 
-        schedstat_set(curr->se.exec_max, max(curr->se.exec_max, delta_exec));
+        schedstat_set(curr->se.statistics.exec_max, max(curr->se.statistics.exec_max, delta_exec));
 
         curr->se.sum_exec_runtime += delta_exec;
         account_group_exec_runtime(curr, delta_exec);
@@ -888,20 +888,20 @@ static void dequeue_rt_entity(struct sched_rt_entity *rt_se)
  * Adding/removing a task to/from a priority array:
  */
 static void
-enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup, bool head)
+enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
 {
         struct sched_rt_entity *rt_se = &p->rt;
 
-        if (wakeup)
+        if (flags & ENQUEUE_WAKEUP)
                 rt_se->timeout = 0;
 
-        enqueue_rt_entity(rt_se, head);
+        enqueue_rt_entity(rt_se, flags & ENQUEUE_HEAD);
 
         if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
                 enqueue_pushable_task(rq, p);
 }
 
-static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
+static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
 {
         struct sched_rt_entity *rt_se = &p->rt;
 
@@ -948,10 +948,9 @@ static void yield_task_rt(struct rq *rq)
 #ifdef CONFIG_SMP
 static int find_lowest_rq(struct task_struct *task);
 
-static int select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
+static int
+select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags)
 {
-        struct rq *rq = task_rq(p);
-
         if (sd_flag != SD_BALANCE_WAKE)
                 return smp_processor_id();
 
diff --git a/kernel/signal.c b/kernel/signal.c
index dbd7fe073c55..906ae5a1779c 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -642,7 +642,7 @@ static inline bool si_fromuser(const struct siginfo *info)
 static int check_kill_permission(int sig, struct siginfo *info,
                                  struct task_struct *t)
 {
-        const struct cred *cred = current_cred(), *tcred;
+        const struct cred *cred, *tcred;
         struct pid *sid;
         int error;
 
@@ -656,8 +656,10 @@ static int check_kill_permission(int sig, struct siginfo *info,
         if (error)
                 return error;
 
+        cred = current_cred();
         tcred = __task_cred(t);
-        if ((cred->euid ^ tcred->suid) &&
+        if (!same_thread_group(current, t) &&
+            (cred->euid ^ tcred->suid) &&
             (cred->euid ^ tcred->uid) &&
             (cred->uid  ^ tcred->suid) &&
             (cred->uid  ^ tcred->uid) &&
@@ -1083,23 +1085,24 @@ force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
 /*
  * Nuke all other threads in the group.
  */
-void zap_other_threads(struct task_struct *p)
+int zap_other_threads(struct task_struct *p)
 {
-        struct task_struct *t;
+        struct task_struct *t = p;
+        int count = 0;
 
         p->signal->group_stop_count = 0;
 
-        for (t = next_thread(p); t != p; t = next_thread(t)) {
-                /*
-                 * Don't bother with already dead threads
-                 */
+        while_each_thread(p, t) {
+                count++;
+
+                /* Don't bother with already dead threads */
                 if (t->exit_state)
                         continue;
-
-                /* SIGKILL will be handled before any pending SIGSTOP */
                 sigaddset(&t->pending.signal, SIGKILL);
                 signal_wake_up(t, 1);
         }
+
+        return count;
 }
 
 struct sighand_struct *lock_task_sighand(struct task_struct *tsk, unsigned long *flags)
@@ -2735,3 +2738,43 @@ void __init signals_init(void)
 {
         sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC);
 }
+
+#ifdef CONFIG_KGDB_KDB
+#include <linux/kdb.h>
+/*
+ * kdb_send_sig_info - Allows kdb to send signals without exposing
+ * signal internals.  This function checks if the required locks are
+ * available before calling the main signal code, to avoid kdb
+ * deadlocks.
+ */
+void
+kdb_send_sig_info(struct task_struct *t, struct siginfo *info)
+{
+        static struct task_struct *kdb_prev_t;
+        int sig, new_t;
+        if (!spin_trylock(&t->sighand->siglock)) {
+                kdb_printf("Can't do kill command now.\n"
+                           "The sigmask lock is held somewhere else in "
+                           "kernel, try again later\n");
+                return;
+        }
+        spin_unlock(&t->sighand->siglock);
+        new_t = kdb_prev_t != t;
+        kdb_prev_t = t;
+        if (t->state != TASK_RUNNING && new_t) {
+                kdb_printf("Process is not RUNNING, sending a signal from "
+                           "kdb risks deadlock\n"
+                           "on the run queue locks. "
+                           "The signal has _not_ been sent.\n"
+                           "Reissue the kill command if you want to risk "
+                           "the deadlock.\n");
+                return;
+        }
+        sig = info->si_signo;
+        if (send_sig_info(sig, info, t))
+                kdb_printf("Fail to deliver Signal %d to process %d.\n",
+                           sig, t->pid);
+        else
+                kdb_printf("Signal %d is sent to process %d.\n", sig, t->pid);
+}
+#endif  /* CONFIG_KGDB_KDB */
diff --git a/kernel/smp.c b/kernel/smp.c
index 3fc697336183..75c970c715d3 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -52,7 +52,7 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
         case CPU_UP_PREPARE_FROZEN:
                 if (!zalloc_cpumask_var_node(&cfd->cpumask, GFP_KERNEL,
                                 cpu_to_node(cpu)))
-                        return NOTIFY_BAD;
+                        return notifier_from_errno(-ENOMEM);
                 break;
 
 #ifdef CONFIG_HOTPLUG_CPU
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 7c1a67ef0274..825e1126008f 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -716,7 +716,7 @@ static int run_ksoftirqd(void * __bind_cpu)
                         preempt_enable_no_resched();
                         cond_resched();
                         preempt_disable();
-                        rcu_sched_qs((long)__bind_cpu);
+                        rcu_note_context_switch((long)__bind_cpu);
                 }
                 preempt_enable();
                 set_current_state(TASK_INTERRUPTIBLE);
@@ -808,7 +808,7 @@ static int __cpuinit cpu_callback(struct notifier_block *nfb,
                 p = kthread_create(run_ksoftirqd, hcpu, "ksoftirqd/%d", hotcpu);
                 if (IS_ERR(p)) {
                         printk("ksoftirqd for %i failed\n", hotcpu);
-                        return NOTIFY_BAD;
+                        return notifier_from_errno(PTR_ERR(p));
                 }
                 kthread_bind(p, hotcpu);
                 per_cpu(ksoftirqd, hotcpu) = p;
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 9bb9fb1bd79c..b4e7431e7c78 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -1,17 +1,384 @@
-/* Copyright 2008, 2005 Rusty Russell rusty@rustcorp.com.au IBM Corporation.
- * GPL v2 and any later version.
+/*
+ * kernel/stop_machine.c
+ *
+ * Copyright (C) 2008, 2005     IBM Corporation.
+ * Copyright (C) 2008, 2005     Rusty Russell rusty@rustcorp.com.au
+ * Copyright (C) 2010           SUSE Linux Products GmbH
+ * Copyright (C) 2010           Tejun Heo <tj@kernel.org>
+ *
+ * This file is released under the GPLv2 and any later version.
  */
+#include <linux/completion.h>
 #include <linux/cpu.h>
-#include <linux/err.h>
+#include <linux/init.h>
 #include <linux/kthread.h>
 #include <linux/module.h>
+#include <linux/percpu.h>
 #include <linux/sched.h>
 #include <linux/stop_machine.h>
-#include <linux/syscalls.h>
 #include <linux/interrupt.h>
+#include <linux/kallsyms.h>
 
 #include <asm/atomic.h>
-#include <asm/uaccess.h>
+
+/*
+ * Structure to determine completion condition and record errors.  May
+ * be shared by works on different cpus.
+ */
+struct cpu_stop_done {
+        atomic_t                nr_todo;        /* nr left to execute */
+        bool                    executed;       /* actually executed? */
+        int                     ret;            /* collected return value */
+        struct completion       completion;     /* fired if nr_todo reaches 0 */
+};
+
+/* the actual stopper, one per every possible cpu, enabled on online cpus */
+struct cpu_stopper {
+        spinlock_t              lock;
+        struct list_head        works;          /* list of pending works */
+        struct task_struct      *thread;        /* stopper thread */
+        bool                    enabled;        /* is this stopper enabled? */
+};
+
+static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper);
+
+static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo)
+{
+        memset(done, 0, sizeof(*done));
+        atomic_set(&done->nr_todo, nr_todo);
+        init_completion(&done->completion);
+}
+
+/* signal completion unless @done is NULL */
+static void cpu_stop_signal_done(struct cpu_stop_done *done, bool executed)
+{
+        if (done) {
+                if (executed)
+                        done->executed = true;
+                if (atomic_dec_and_test(&done->nr_todo))
+                        complete(&done->completion);
+        }
+}
+
+/* queue @work to @stopper.  if offline, @work is completed immediately */
+static void cpu_stop_queue_work(struct cpu_stopper *stopper,
+                                struct cpu_stop_work *work)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&stopper->lock, flags);
+
+        if (stopper->enabled) {
+                list_add_tail(&work->list, &stopper->works);
+                wake_up_process(stopper->thread);
+        } else
+                cpu_stop_signal_done(work->done, false);
+
+        spin_unlock_irqrestore(&stopper->lock, flags);
+}
+
+/**
+ * stop_one_cpu - stop a cpu
+ * @cpu: cpu to stop
+ * @fn: function to execute
+ * @arg: argument to @fn
+ *
+ * Execute @fn(@arg) on @cpu.  @fn is run in a process context with
+ * the highest priority preempting any task on the cpu and
+ * monopolizing it.  This function returns after the execution is
+ * complete.
+ *
+ * This function doesn't guarantee @cpu stays online till @fn
+ * completes.  If @cpu goes down in the middle, execution may happen
+ * partially or fully on different cpus.  @fn should either be ready
+ * for that or the caller should ensure that @cpu stays online until
+ * this function completes.
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * -ENOENT if @fn(@arg) was not executed because @cpu was offline;
+ * otherwise, the return value of @fn.
+ */
+int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg)
+{
+        struct cpu_stop_done done;
+        struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done };
+
+        cpu_stop_init_done(&done, 1);
+        cpu_stop_queue_work(&per_cpu(cpu_stopper, cpu), &work);
+        wait_for_completion(&done.completion);
+        return done.executed ? done.ret : -ENOENT;
+}
+
+/**
+ * stop_one_cpu_nowait - stop a cpu but don't wait for completion
+ * @cpu: cpu to stop
+ * @fn: function to execute
+ * @arg: argument to @fn
+ *
+ * Similar to stop_one_cpu() but doesn't wait for completion.  The
+ * caller is responsible for ensuring @work_buf is currently unused
+ * and will remain untouched until stopper starts executing @fn.
+ *
+ * CONTEXT:
+ * Don't care.
+ */
+void stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
+                        struct cpu_stop_work *work_buf)
+{
+        *work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, };
+        cpu_stop_queue_work(&per_cpu(cpu_stopper, cpu), work_buf);
+}
+
+/* static data for stop_cpus */
+static DEFINE_MUTEX(stop_cpus_mutex);
+static DEFINE_PER_CPU(struct cpu_stop_work, stop_cpus_work);
+
+int __stop_cpus(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg)
+{
+        struct cpu_stop_work *work;
+        struct cpu_stop_done done;
+        unsigned int cpu;
+
+        /* initialize works and done */
+        for_each_cpu(cpu, cpumask) {
+                work = &per_cpu(stop_cpus_work, cpu);
+                work->fn = fn;
+                work->arg = arg;
+                work->done = &done;
+        }
+        cpu_stop_init_done(&done, cpumask_weight(cpumask));
+
+        /*
+         * Disable preemption while queueing to avoid getting
+         * preempted by a stopper which might wait for other stoppers
+         * to enter @fn which can lead to deadlock.
+         */
+        preempt_disable();
+        for_each_cpu(cpu, cpumask)
+                cpu_stop_queue_work(&per_cpu(cpu_stopper, cpu),
+                                    &per_cpu(stop_cpus_work, cpu));
+        preempt_enable();
+
+        wait_for_completion(&done.completion);
+        return done.executed ? done.ret : -ENOENT;
+}
+
+/**
+ * stop_cpus - stop multiple cpus
+ * @cpumask: cpus to stop
+ * @fn: function to execute
+ * @arg: argument to @fn
+ *
+ * Execute @fn(@arg) on online cpus in @cpumask.  On each target cpu,
+ * @fn is run in a process context with the highest priority
+ * preempting any task on the cpu and monopolizing it.  This function
+ * returns after all executions are complete.
+ *
+ * This function doesn't guarantee the cpus in @cpumask stay online
+ * till @fn completes.  If some cpus go down in the middle, execution
+ * on the cpu may happen partially or fully on different cpus.  @fn
+ * should either be ready for that or the caller should ensure that
+ * the cpus stay online until this function completes.
+ *
+ * All stop_cpus() calls are serialized making it safe for @fn to wait
+ * for all cpus to start executing it.
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * -ENOENT if @fn(@arg) was not executed at all because all cpus in
+ * @cpumask were offline; otherwise, 0 if all executions of @fn
+ * returned 0, any non zero return value if any returned non zero.
+ */
+int stop_cpus(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg)
+{
+        int ret;
+
+        /* static works are used, process one request at a time */
+        mutex_lock(&stop_cpus_mutex);
+        ret = __stop_cpus(cpumask, fn, arg);
+        mutex_unlock(&stop_cpus_mutex);
+        return ret;
+}
+
+/**
+ * try_stop_cpus - try to stop multiple cpus
+ * @cpumask: cpus to stop
+ * @fn: function to execute
+ * @arg: argument to @fn
+ *
+ * Identical to stop_cpus() except that it fails with -EAGAIN if
+ * someone else is already using the facility.
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * -EAGAIN if someone else is already stopping cpus, -ENOENT if
+ * @fn(@arg) was not executed at all because all cpus in @cpumask were
+ * offline; otherwise, 0 if all executions of @fn returned 0, any non
+ * zero return value if any returned non zero.
+ */
+int try_stop_cpus(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg)
+{
+        int ret;
+
+        /* static works are used, process one request at a time */
+        if (!mutex_trylock(&stop_cpus_mutex))
+                return -EAGAIN;
+        ret = __stop_cpus(cpumask, fn, arg);
+        mutex_unlock(&stop_cpus_mutex);
+        return ret;
+}
+
+static int cpu_stopper_thread(void *data)
+{
+        struct cpu_stopper *stopper = data;
+        struct cpu_stop_work *work;
+        int ret;
+
+repeat:
+        set_current_state(TASK_INTERRUPTIBLE);  /* mb paired w/ kthread_stop */
+
+        if (kthread_should_stop()) {
+                __set_current_state(TASK_RUNNING);
+                return 0;
+        }
+
+        work = NULL;
+        spin_lock_irq(&stopper->lock);
+        if (!list_empty(&stopper->works)) {
+                work = list_first_entry(&stopper->works,
+                                        struct cpu_stop_work, list);
+                list_del_init(&work->list);
+        }
+        spin_unlock_irq(&stopper->lock);
+
+        if (work) {
+                cpu_stop_fn_t fn = work->fn;
+                void *arg = work->arg;
+                struct cpu_stop_done *done = work->done;
+                char ksym_buf[KSYM_NAME_LEN];
+
+                __set_current_state(TASK_RUNNING);
+
+                /* cpu stop callbacks are not allowed to sleep */
+                preempt_disable();
+
+                ret = fn(arg);
+                if (ret)
+                        done->ret = ret;
+
+                /* restore preemption and check it's still balanced */
+                preempt_enable();
+                WARN_ONCE(preempt_count(),
+                          "cpu_stop: %s(%p) leaked preempt count\n",
+                          kallsyms_lookup((unsigned long)fn, NULL, NULL, NULL,
+                                          ksym_buf), arg);
+
+                cpu_stop_signal_done(done, true);
+        } else
+                schedule();
+
+        goto repeat;
+}
+
+/* manage stopper for a cpu, mostly lifted from sched migration thread mgmt */
+static int __cpuinit cpu_stop_cpu_callback(struct notifier_block *nfb,
+                                           unsigned long action, void *hcpu)
+{
+        struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
+        unsigned int cpu = (unsigned long)hcpu;
+        struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
+        struct task_struct *p;
+
+        switch (action & ~CPU_TASKS_FROZEN) {
+        case CPU_UP_PREPARE:
+                BUG_ON(stopper->thread || stopper->enabled ||
+                       !list_empty(&stopper->works));
+                p = kthread_create(cpu_stopper_thread, stopper, "migration/%d",
+                                   cpu);
+                if (IS_ERR(p))
+                        return NOTIFY_BAD;
+                sched_setscheduler_nocheck(p, SCHED_FIFO, &param);
+                get_task_struct(p);
+                stopper->thread = p;
+                break;
+
+        case CPU_ONLINE:
+                kthread_bind(stopper->thread, cpu);
+                /* strictly unnecessary, as first user will wake it */
+                wake_up_process(stopper->thread);
+                /* mark enabled */
+                spin_lock_irq(&stopper->lock);
+                stopper->enabled = true;
+                spin_unlock_irq(&stopper->lock);
+                break;
+
+#ifdef CONFIG_HOTPLUG_CPU
+        case CPU_UP_CANCELED:
+        case CPU_DEAD:
+        {
+                struct cpu_stop_work *work;
+
+                /* kill the stopper */
+                kthread_stop(stopper->thread);
+                /* drain remaining works */
+                spin_lock_irq(&stopper->lock);
+                list_for_each_entry(work, &stopper->works, list)
+                        cpu_stop_signal_done(work->done, false);
+                stopper->enabled = false;
+                spin_unlock_irq(&stopper->lock);
+                /* release the stopper */
+                put_task_struct(stopper->thread);
+                stopper->thread = NULL;
+                break;
+        }
+#endif
+        }
+
+        return NOTIFY_OK;
+}
+
+/*
+ * Give it a higher priority so that cpu stopper is available to other
+ * cpu notifiers.  It currently shares the same priority as sched
+ * migration_notifier.
+ */
+static struct notifier_block __cpuinitdata cpu_stop_cpu_notifier = {
+        .notifier_call  = cpu_stop_cpu_callback,
+        .priority       = 10,
+};
+
+static int __init cpu_stop_init(void)
+{
+        void *bcpu = (void *)(long)smp_processor_id();
+        unsigned int cpu;
+        int err;
+
+        for_each_possible_cpu(cpu) {
+                struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
+
+                spin_lock_init(&stopper->lock);
+                INIT_LIST_HEAD(&stopper->works);
+        }
+
+        /* start one for the boot cpu */
+        err = cpu_stop_cpu_callback(&cpu_stop_cpu_notifier, CPU_UP_PREPARE,
+                                    bcpu);
+        BUG_ON(err == NOTIFY_BAD);
+        cpu_stop_cpu_callback(&cpu_stop_cpu_notifier, CPU_ONLINE, bcpu);
+        register_cpu_notifier(&cpu_stop_cpu_notifier);
+
+        return 0;
+}
+early_initcall(cpu_stop_init);
+
+#ifdef CONFIG_STOP_MACHINE
 
 /* This controls the threads on each CPU. */
 enum stopmachine_state {
@@ -26,174 +393,94 @@ enum stopmachine_state {
         /* Exit */
         STOPMACHINE_EXIT,
 };
-static enum stopmachine_state state;
 
 struct stop_machine_data {
-        int (*fn)(void *);
-        void *data;
-        int fnret;
+        int                     (*fn)(void *);
+        void                    *data;
+        /* Like num_online_cpus(), but hotplug cpu uses us, so we need this. */
+        unsigned int            num_threads;
+        const struct cpumask    *active_cpus;
+
+        enum stopmachine_state  state;
+        atomic_t                thread_ack;
 };
 
-/* Like num_online_cpus(), but hotplug cpu uses us, so we need this. */
-static unsigned int num_threads;
-static atomic_t thread_ack;
-static DEFINE_MUTEX(lock);
-/* setup_lock protects refcount, stop_machine_wq and stop_machine_work. */
-static DEFINE_MUTEX(setup_lock);
-/* Users of stop_machine. */
-static int refcount;
-static struct workqueue_struct *stop_machine_wq;
-static struct stop_machine_data active, idle;
-static const struct cpumask *active_cpus;
-static void __percpu *stop_machine_work;
-
-static void set_state(enum stopmachine_state newstate)
+static void set_state(struct stop_machine_data *smdata,
+                      enum stopmachine_state newstate)
 {
         /* Reset ack counter. */
-        atomic_set(&thread_ack, num_threads);
+        atomic_set(&smdata->thread_ack, smdata->num_threads);
         smp_wmb();
-        state = newstate;
+        smdata->state = newstate;
 }
 
 /* Last one to ack a state moves to the next state. */
-static void ack_state(void)
+static void ack_state(struct stop_machine_data *smdata)
 {
-        if (atomic_dec_and_test(&thread_ack))
-                set_state(state + 1);
+        if (atomic_dec_and_test(&smdata->thread_ack))
+                set_state(smdata, smdata->state + 1);
 }
 
-/* This is the actual function which stops the CPU. It runs
- * in the context of a dedicated stopmachine workqueue. */
-static void stop_cpu(struct work_struct *unused)
+/* This is the cpu_stop function which stops the CPU. */
+static int stop_machine_cpu_stop(void *data)
 {
+        struct stop_machine_data *smdata = data;
         enum stopmachine_state curstate = STOPMACHINE_NONE;
-        struct stop_machine_data *smdata = &idle;
-        int cpu = smp_processor_id();
-        int err;
+        int cpu = smp_processor_id(), err = 0;
+        bool is_active;
+
+        if (!smdata->active_cpus)
+                is_active = cpu == cpumask_first(cpu_online_mask);
+        else
+                is_active = cpumask_test_cpu(cpu, smdata->active_cpus);
 
-        if (!active_cpus) {
-                if (cpu == cpumask_first(cpu_online_mask))
-                        smdata = &active;
-        } else {
-                if (cpumask_test_cpu(cpu, active_cpus))
-                        smdata = &active;
-        }
         /* Simple state machine */
         do {
                 /* Chill out and ensure we re-read stopmachine_state. */
                 cpu_relax();
-                if (state != curstate) {
-                        curstate = state;
+                if (smdata->state != curstate) {
+                        curstate = smdata->state;
                         switch (curstate) {
                         case STOPMACHINE_DISABLE_IRQ:
                                 local_irq_disable();
                                 hard_irq_disable();
                                 break;
                         case STOPMACHINE_RUN:
-                                /* On multiple CPUs only a single error code
-                                 * is needed to tell that something failed. */
-                                err = smdata->fn(smdata->data);
-                                if (err)
-                                        smdata->fnret = err;
+                                if (is_active)
+                                        err = smdata->fn(smdata->data);
                                 break;
                         default:
                                 break;
                         }
-                        ack_state();
+                        ack_state(smdata);
                 }
         } while (curstate != STOPMACHINE_EXIT);
 
         local_irq_enable();
+        return err;
 }
 
-/* Callback for CPUs which aren't supposed to do anything. */
-static int chill(void *unused)
-{
-        return 0;
-}
-
-int stop_machine_create(void)
-{
-        mutex_lock(&setup_lock);
-        if (refcount)
-                goto done;
-        stop_machine_wq = create_rt_workqueue("kstop");
-        if (!stop_machine_wq)
-                goto err_out;
-        stop_machine_work = alloc_percpu(struct work_struct);
-        if (!stop_machine_work)
-                goto err_out;
-done:
-        refcount++;
-        mutex_unlock(&setup_lock);
-        return 0;
-
-err_out:
-        if (stop_machine_wq)
-                destroy_workqueue(stop_machine_wq);
-        mutex_unlock(&setup_lock);
-        return -ENOMEM;
-}
-EXPORT_SYMBOL_GPL(stop_machine_create);
-
-void stop_machine_destroy(void)
-{
-        mutex_lock(&setup_lock);
-        refcount--;
-        if (refcount)
-                goto done;
-        destroy_workqueue(stop_machine_wq);
-        free_percpu(stop_machine_work);
-done:
-        mutex_unlock(&setup_lock);
-}
-EXPORT_SYMBOL_GPL(stop_machine_destroy);
-
 int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus)
 {
-        struct work_struct *sm_work;
-        int i, ret;
-
-        /* Set up initial state. */
-        mutex_lock(&lock);
-        num_threads = num_online_cpus();
-        active_cpus = cpus;
-        active.fn = fn;
-        active.data = data;
-        active.fnret = 0;
-        idle.fn = chill;
-        idle.data = NULL;
-
-        set_state(STOPMACHINE_PREPARE);
-
-        /* Schedule the stop_cpu work on all cpus: hold this CPU so one
-         * doesn't hit this CPU until we're ready. */
-        get_cpu();
-        for_each_online_cpu(i) {
-                sm_work = per_cpu_ptr(stop_machine_work, i);
-                INIT_WORK(sm_work, stop_cpu);
-                queue_work_on(i, stop_machine_wq, sm_work);
-        }
-        /* This will release the thread on our CPU. */
-        put_cpu();
-        flush_workqueue(stop_machine_wq);
-        ret = active.fnret;
-        mutex_unlock(&lock);
-        return ret;
+        struct stop_machine_data smdata = { .fn = fn, .data = data,
+                                            .num_threads = num_online_cpus(),
+                                            .active_cpus = cpus };
+
+        /* Set the initial state and stop all online cpus. */
+        set_state(&smdata, STOPMACHINE_PREPARE);
+        return stop_cpus(cpu_online_mask, stop_machine_cpu_stop, &smdata);
 }
 
 int stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus)
 {
         int ret;
 
-        ret = stop_machine_create();
-        if (ret)
-                return ret;
         /* No CPUs can come up or down during this. */
         get_online_cpus();
         ret = __stop_machine(fn, data, cpus);
         put_online_cpus();
-        stop_machine_destroy();
         return ret;
 }
 EXPORT_SYMBOL_GPL(stop_machine);
+
+#endif  /* CONFIG_STOP_MACHINE */
diff --git a/kernel/sys.c b/kernel/sys.c
index 7cb426a58965..e83ddbbaf89d 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -492,10 +492,6 @@ SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
                 return -ENOMEM;
         old = current_cred();
 
-        retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE);
-        if (retval)
-                goto error;
-
         retval = -EPERM;
         if (rgid != (gid_t) -1) {
                 if (old->gid == rgid ||
@@ -543,10 +539,6 @@ SYSCALL_DEFINE1(setgid, gid_t, gid)
                 return -ENOMEM;
         old = current_cred();
 
-        retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID);
-        if (retval)
-                goto error;
-
         retval = -EPERM;
         if (capable(CAP_SETGID))
                 new->gid = new->egid = new->sgid = new->fsgid = gid;
@@ -610,10 +602,6 @@ SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
                 return -ENOMEM;
         old = current_cred();
 
-        retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE);
-        if (retval)
-                goto error;
-
         retval = -EPERM;
         if (ruid != (uid_t) -1) {
                 new->uid = ruid;
@@ -675,10 +663,6 @@ SYSCALL_DEFINE1(setuid, uid_t, uid)
                 return -ENOMEM;
         old = current_cred();
 
-        retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID);
-        if (retval)
-                goto error;
-
         retval = -EPERM;
         if (capable(CAP_SETUID)) {
                 new->suid = new->uid = uid;
@@ -719,9 +703,6 @@ SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
         if (!new)
                 return -ENOMEM;
 
-        retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES);
-        if (retval)
-                goto error;
         old = current_cred();
 
         retval = -EPERM;
@@ -788,10 +769,6 @@ SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
                 return -ENOMEM;
         old = current_cred();
 
-        retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES);
-        if (retval)
-                goto error;
-
         retval = -EPERM;
         if (!capable(CAP_SETGID)) {
                 if (rgid != (gid_t) -1 && rgid != old->gid &&
@@ -851,9 +828,6 @@ SYSCALL_DEFINE1(setfsuid, uid_t, uid)
         old = current_cred();
         old_fsuid = old->fsuid;
 
-        if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0)
-                goto error;
-
         if (uid == old->uid  || uid == old->euid  ||
             uid == old->suid || uid == old->fsuid ||
             capable(CAP_SETUID)) {
@@ -864,7 +838,6 @@ SYSCALL_DEFINE1(setfsuid, uid_t, uid)
                 }
         }
 
-error:
         abort_creds(new);
         return old_fsuid;
 
@@ -888,9 +861,6 @@ SYSCALL_DEFINE1(setfsgid, gid_t, gid)
         old = current_cred();
         old_fsgid = old->fsgid;
 
-        if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS))
-                goto error;
-
         if (gid == old->gid  || gid == old->egid  ||
             gid == old->sgid || gid == old->fsgid ||
             capable(CAP_SETGID)) {
@@ -900,7 +870,6 @@ SYSCALL_DEFINE1(setfsgid, gid_t, gid)
                 }
         }
 
-error:
         abort_creds(new);
         return old_fsgid;
 
@@ -1663,9 +1632,9 @@ SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
 
 char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff";
 
-static void argv_cleanup(char **argv, char **envp)
+static void argv_cleanup(struct subprocess_info *info)
 {
-        argv_free(argv);
+        argv_free(info->argv);
 }
 
 /**
@@ -1699,7 +1668,7 @@ int orderly_poweroff(bool force)
                 goto out;
         }
 
-        call_usermodehelper_setcleanup(info, argv_cleanup);
+        call_usermodehelper_setfns(info, NULL, argv_cleanup, NULL);
 
         ret = call_usermodehelper_exec(info, UMH_NO_WAIT);
 
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 8686b0f5fc12..997080f00e0b 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -37,6 +37,7 @@
 #include <linux/highuid.h>
 #include <linux/writeback.h>
 #include <linux/ratelimit.h>
+#include <linux/compaction.h>
 #include <linux/hugetlb.h>
 #include <linux/initrd.h>
 #include <linux/key.h>
@@ -52,6 +53,7 @@
 #include <linux/slow-work.h>
 #include <linux/perf_event.h>
 #include <linux/kprobes.h>
+#include <linux/pipe_fs_i.h>
 
 #include <asm/uaccess.h>
 #include <asm/processor.h>
@@ -163,6 +165,27 @@ static int proc_taint(struct ctl_table *table, int write,
                                void __user *buffer, size_t *lenp, loff_t *ppos);
 #endif
 
+#ifdef CONFIG_MAGIC_SYSRQ
+static int __sysrq_enabled; /* Note: sysrq code ises it's own private copy */
+
+static int sysrq_sysctl_handler(ctl_table *table, int write,
+                                void __user *buffer, size_t *lenp,
+                                loff_t *ppos)
+{
+        int error;
+
+        error = proc_dointvec(table, write, buffer, lenp, ppos);
+        if (error)
+                return error;
+
+        if (write)
+                sysrq_toggle_support(__sysrq_enabled);
+
+        return 0;
+}
+
+#endif
+
 static struct ctl_table root_table[];
 static struct ctl_table_root sysctl_table_root;
 static struct ctl_table_header root_table_header = {
@@ -240,6 +263,11 @@ static int min_sched_shares_ratelimit = 100000; /* 100 usec */
 static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */
 #endif
 
+#ifdef CONFIG_COMPACTION
+static int min_extfrag_threshold;
+static int max_extfrag_threshold = 1000;
+#endif
+
 static struct ctl_table kern_table[] = {
         {
                 .procname       = "sched_child_runs_first",
@@ -567,7 +595,7 @@ static struct ctl_table kern_table[] = {
                 .data           = &__sysrq_enabled,
                 .maxlen         = sizeof (int),
                 .mode           = 0644,
-                .proc_handler   = proc_dointvec,
+                .proc_handler   = sysrq_sysctl_handler,
         },
 #endif
 #ifdef CONFIG_PROC_SYSCTL
@@ -621,7 +649,7 @@ static struct ctl_table kern_table[] = {
 #endif
         {
                 .procname       = "userprocess_debug",
-                .data           = &sysctl_userprocess_debug,
+                .data           = &show_unhandled_signals,
                 .maxlen         = sizeof(int),
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec,
@@ -1099,6 +1127,25 @@ static struct ctl_table vm_table[] = {
                 .mode           = 0644,
                 .proc_handler   = drop_caches_sysctl_handler,
         },
+#ifdef CONFIG_COMPACTION
+        {
+                .procname       = "compact_memory",
+                .data           = &sysctl_compact_memory,
+                .maxlen         = sizeof(int),
+                .mode           = 0200,
+                .proc_handler   = sysctl_compaction_handler,
+        },
+        {
+                .procname       = "extfrag_threshold",
+                .data           = &sysctl_extfrag_threshold,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = sysctl_extfrag_handler,
+                .extra1         = &min_extfrag_threshold,
+                .extra2         = &max_extfrag_threshold,
+        },
+
+#endif /* CONFIG_COMPACTION */
         {
                 .procname       = "min_free_kbytes",
                 .data           = &min_free_kbytes,
@@ -1423,6 +1470,14 @@ static struct ctl_table fs_table[] = {
                 .child          = binfmt_misc_table,
         },
 #endif
+        {
+                .procname       = "pipe-max-pages",
+                .data           = &pipe_max_pages,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec_minmax,
+                .extra1         = &two,
+        },
 /*
  * NOTE: do not add new entries to this table unless you have read
  * Documentation/sysctl/ctl_unnumbered.txt
@@ -1431,7 +1486,8 @@ static struct ctl_table fs_table[] = {
 };
 
 static struct ctl_table debug_table[] = {
-#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC)
+#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
+    defined(CONFIG_S390)
         {
                 .procname       = "exception-trace",
                 .data           = &show_unhandled_signals,
@@ -2040,8 +2096,132 @@ int proc_dostring(struct ctl_table *table, int write,
                                buffer, lenp, ppos);
 }
 
+static size_t proc_skip_spaces(char **buf)
+{
+        size_t ret;
+        char *tmp = skip_spaces(*buf);
+        ret = tmp - *buf;
+        *buf = tmp;
+        return ret;
+}
+
+static void proc_skip_char(char **buf, size_t *size, const char v)
+{
+        while (*size) {
+                if (**buf != v)
+                        break;
+                (*size)--;
+                (*buf)++;
+        }
+}
+
+#define TMPBUFLEN 22
+/**
+ * proc_get_long - reads an ASCII formatted integer from a user buffer
+ *
+ * @buf: a kernel buffer
+ * @size: size of the kernel buffer
+ * @val: this is where the number will be stored
+ * @neg: set to %TRUE if number is negative
+ * @perm_tr: a vector which contains the allowed trailers
+ * @perm_tr_len: size of the perm_tr vector
+ * @tr: pointer to store the trailer character
+ *
+ * In case of success %0 is returned and @buf and @size are updated with
+ * the amount of bytes read. If @tr is non-NULL and a trailing
+ * character exists (size is non-zero after returning from this
+ * function), @tr is updated with the trailing character.
+ */
+static int proc_get_long(char **buf, size_t *size,
+                          unsigned long *val, bool *neg,
+                          const char *perm_tr, unsigned perm_tr_len, char *tr)
+{
+        int len;
+        char *p, tmp[TMPBUFLEN];
+
+        if (!*size)
+                return -EINVAL;
+
+        len = *size;
+        if (len > TMPBUFLEN - 1)
+                len = TMPBUFLEN - 1;
+
+        memcpy(tmp, *buf, len);
+
+        tmp[len] = 0;
+        p = tmp;
+        if (*p == '-' && *size > 1) {
+                *neg = true;
+                p++;
+        } else
+                *neg = false;
+        if (!isdigit(*p))
+                return -EINVAL;
+
+        *val = simple_strtoul(p, &p, 0);
+
+        len = p - tmp;
+
+        /* We don't know if the next char is whitespace thus we may accept
+         * invalid integers (e.g. 1234...a) or two integers instead of one
+         * (e.g. 123...1). So lets not allow such large numbers. */
+        if (len == TMPBUFLEN - 1)
+                return -EINVAL;
+
+        if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
+                return -EINVAL;
+
+        if (tr && (len < *size))
+                *tr = *p;
+
+        *buf += len;
+        *size -= len;
+
+        return 0;
+}
+
+/**
+ * proc_put_long - converts an integer to a decimal ASCII formatted string
+ *
+ * @buf: the user buffer
+ * @size: the size of the user buffer
+ * @val: the integer to be converted
+ * @neg: sign of the number, %TRUE for negative
+ *
+ * In case of success %0 is returned and @buf and @size are updated with
+ * the amount of bytes written.
+ */
+static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
+                          bool neg)
+{
+        int len;
+        char tmp[TMPBUFLEN], *p = tmp;
+
+        sprintf(p, "%s%lu", neg ? "-" : "", val);
+        len = strlen(tmp);
+        if (len > *size)
+                len = *size;
+        if (copy_to_user(*buf, tmp, len))
+                return -EFAULT;
+        *size -= len;
+        *buf += len;
+        return 0;
+}
+#undef TMPBUFLEN
+
+static int proc_put_char(void __user **buf, size_t *size, char c)
+{
+        if (*size) {
+                char __user **buffer = (char __user **)buf;
+                if (put_user(c, *buffer))
+                        return -EFAULT;
+                (*size)--, (*buffer)++;
+                *buf = *buffer;
+        }
+        return 0;
+}
 
-static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
                                  int *valp,
                                  int write, void *data)
 {
@@ -2050,33 +2230,31 @@ static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
         } else {
                 int val = *valp;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         *lvalp = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         *lvalp = (unsigned long)val;
                 }
         }
         return 0;
 }
 
+static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
+
 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
                   int write, void __user *buffer,
                   size_t *lenp, loff_t *ppos,
-                  int (*conv)(int *negp, unsigned long *lvalp, int *valp,
+                  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
                               int write, void *data),
                   void *data)
 {
-#define TMPBUFLEN 21
-        int *i, vleft, first = 1, neg;
-        unsigned long lval;
-        size_t left, len;
+        int *i, vleft, first = 1, err = 0;
+        unsigned long page = 0;
+        size_t left;
+        char *kbuf;
         
-        char buf[TMPBUFLEN], *p;
-        char __user *s = buffer;
-        
-        if (!tbl_data || !table->maxlen || !*lenp ||
-            (*ppos && !write)) {
+        if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
                 *lenp = 0;
                 return 0;
         }
@@ -2088,89 +2266,71 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
         if (!conv)
                 conv = do_proc_dointvec_conv;
 
+        if (write) {
+                if (left > PAGE_SIZE - 1)
+                        left = PAGE_SIZE - 1;
+                page = __get_free_page(GFP_TEMPORARY);
+                kbuf = (char *) page;
+                if (!kbuf)
+                        return -ENOMEM;
+                if (copy_from_user(kbuf, buffer, left)) {
+                        err = -EFAULT;
+                        goto free;
+                }
+                kbuf[left] = 0;
+        }
+
         for (; left && vleft--; i++, first=0) {
+                unsigned long lval;
+                bool neg;
+
                 if (write) {
-                        while (left) {
-                                char c;
-                                if (get_user(c, s))
-                                        return -EFAULT;
-                                if (!isspace(c))
-                                        break;
-                                left--;
-                                s++;
-                        }
+                        left -= proc_skip_spaces(&kbuf);
+
                         if (!left)
                                 break;
-                        neg = 0;
-                        len = left;
-                        if (len > sizeof(buf) - 1)
-                                len = sizeof(buf) - 1;
-                        if (copy_from_user(buf, s, len))
-                                return -EFAULT;
-                        buf[len] = 0;
-                        p = buf;
-                        if (*p == '-' && left > 1) {
-                                neg = 1;
-                                p++;
-                        }
-                        if (*p < '0' || *p > '9')
+                        err = proc_get_long(&kbuf, &left, &lval, &neg,
+                                             proc_wspace_sep,
+                                             sizeof(proc_wspace_sep), NULL);
+                        if (err)
                                 break;
-
-                        lval = simple_strtoul(p, &p, 0);
-
-                        len = p-buf;
-                        if ((len < left) && *p && !isspace(*p))
-                                break;
-                        s += len;
-                        left -= len;
-
-                        if (conv(&neg, &lval, i, 1, data))
+                        if (conv(&neg, &lval, i, 1, data)) {
+                                err = -EINVAL;
                                 break;
+                        }
                 } else {
-                        p = buf;
+                        if (conv(&neg, &lval, i, 0, data)) {
+                                err = -EINVAL;
+                                break;
+                        }
                         if (!first)
-                                *p++ = '\t';
-        
-                        if (conv(&neg, &lval, i, 0, data))
+                                err = proc_put_char(&buffer, &left, '\t');
+                        if (err)
+                                break;
+                        err = proc_put_long(&buffer, &left, lval, neg);
+                        if (err)
                                 break;
-
-                        sprintf(p, "%s%lu", neg ? "-" : "", lval);
-                        len = strlen(buf);
-                        if (len > left)
-                                len = left;
-                        if(copy_to_user(s, buf, len))
-                                return -EFAULT;
-                        left -= len;
-                        s += len;
                 }
         }
 
-        if (!write && !first && left) {
-                if(put_user('\n', s))
-                        return -EFAULT;
-                left--, s++;
-        }
+        if (!write && !first && left && !err)
+                err = proc_put_char(&buffer, &left, '\n');
+        if (write && !err && left)
+                left -= proc_skip_spaces(&kbuf);
+free:
         if (write) {
-                while (left) {
-                        char c;
-                        if (get_user(c, s++))
-                                return -EFAULT;
-                        if (!isspace(c))
-                                break;
-                        left--;
-                }
+                free_page(page);
+                if (first)
+                        return err ? : -EINVAL;
         }
-        if (write && first)
-                return -EINVAL;
         *lenp -= left;
         *ppos += *lenp;
-        return 0;
-#undef TMPBUFLEN
+        return err;
 }
 
 static int do_proc_dointvec(struct ctl_table *table, int write,
                   void __user *buffer, size_t *lenp, loff_t *ppos,
-                  int (*conv)(int *negp, unsigned long *lvalp, int *valp,
+                  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
                               int write, void *data),
                   void *data)
 {
@@ -2238,8 +2398,8 @@ struct do_proc_dointvec_minmax_conv_param {
         int *max;
 };
 
-static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 
-                                        int *valp, 
+static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
+                                        int *valp,
                                         int write, void *data)
 {
         struct do_proc_dointvec_minmax_conv_param *param = data;
@@ -2252,10 +2412,10 @@ static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
         } else {
                 int val = *valp;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         *lvalp = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         *lvalp = (unsigned long)val;
                 }
         }
@@ -2295,102 +2455,78 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int
                                      unsigned long convmul,
                                      unsigned long convdiv)
 {
-#define TMPBUFLEN 21
-        unsigned long *i, *min, *max, val;
-        int vleft, first=1, neg;
-        size_t len, left;
-        char buf[TMPBUFLEN], *p;
-        char __user *s = buffer;
-        
-        if (!data || !table->maxlen || !*lenp ||
-            (*ppos && !write)) {
+        unsigned long *i, *min, *max;
+        int vleft, first = 1, err = 0;
+        unsigned long page = 0;
+        size_t left;
+        char *kbuf;
+
+        if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
                 *lenp = 0;
                 return 0;
         }
-        
+
         i = (unsigned long *) data;
         min = (unsigned long *) table->extra1;
         max = (unsigned long *) table->extra2;
         vleft = table->maxlen / sizeof(unsigned long);
         left = *lenp;
-        
+
+        if (write) {
+                if (left > PAGE_SIZE - 1)
+                        left = PAGE_SIZE - 1;
+                page = __get_free_page(GFP_TEMPORARY);
+                kbuf = (char *) page;
+                if (!kbuf)
+                        return -ENOMEM;
+                if (copy_from_user(kbuf, buffer, left)) {
+                        err = -EFAULT;
+                        goto free;
+                }
+                kbuf[left] = 0;
+        }
+
         for (; left && vleft--; i++, min++, max++, first=0) {
+                unsigned long val;
+
                 if (write) {
-                        while (left) {
-                                char c;
-                                if (get_user(c, s))
-                                        return -EFAULT;
-                                if (!isspace(c))
-                                        break;
-                                left--;
-                                s++;
-                        }
-                        if (!left)
-                                break;
-                        neg = 0;
-                        len = left;
-                        if (len > TMPBUFLEN-1)
-                                len = TMPBUFLEN-1;
-                        if (copy_from_user(buf, s, len))
-                                return -EFAULT;
-                        buf[len] = 0;
-                        p = buf;
-                        if (*p == '-' && left > 1) {
-                                neg = 1;
-                                p++;
-                        }
-                        if (*p < '0' || *p > '9')
-                                break;
-                        val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
-                        len = p-buf;
-                        if ((len < left) && *p && !isspace(*p))
+                        bool neg;
+
+                        left -= proc_skip_spaces(&kbuf);
+
+                        err = proc_get_long(&kbuf, &left, &val, &neg,
+                                             proc_wspace_sep,
+                                             sizeof(proc_wspace_sep), NULL);
+                        if (err)
                                 break;
                         if (neg)
-                                val = -val;
-                        s += len;
-                        left -= len;
-
-                        if(neg)
                                 continue;
                         if ((min && val < *min) || (max && val > *max))
                                 continue;
                         *i = val;
                 } else {
-                        p = buf;
+                        val = convdiv * (*i) / convmul;
                         if (!first)
-                                *p++ = '\t';
-                        sprintf(p, "%lu", convdiv * (*i) / convmul);
-                        len = strlen(buf);
-                        if (len > left)
-                                len = left;
-                        if(copy_to_user(s, buf, len))
-                                return -EFAULT;
-                        left -= len;
-                        s += len;
+                                err = proc_put_char(&buffer, &left, '\t');
+                        err = proc_put_long(&buffer, &left, val, false);
+                        if (err)
+                                break;
                 }
         }
 
-        if (!write && !first && left) {
-                if(put_user('\n', s))
-                        return -EFAULT;
-                left--, s++;
-        }
+        if (!write && !first && left && !err)
+                err = proc_put_char(&buffer, &left, '\n');
+        if (write && !err)
+                left -= proc_skip_spaces(&kbuf);
+free:
         if (write) {
-                while (left) {
-                        char c;
-                        if (get_user(c, s++))
-                                return -EFAULT;
-                        if (!isspace(c))
-                                break;
-                        left--;
-                }
+                free_page(page);
+                if (first)
+                        return err ? : -EINVAL;
         }
-        if (write && first)
-                return -EINVAL;
         *lenp -= left;
         *ppos += *lenp;
-        return 0;
-#undef TMPBUFLEN
+        return err;
 }
 
 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
@@ -2451,7 +2587,7 @@ int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
 }
 
 
-static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
                                          int *valp,
                                          int write, void *data)
 {
@@ -2463,10 +2599,10 @@ static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
                 int val = *valp;
                 unsigned long lval;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         lval = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         lval = (unsigned long)val;
                 }
                 *lvalp = lval / HZ;
@@ -2474,7 +2610,7 @@ static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
         return 0;
 }
 
-static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
                                                 int *valp,
                                                 int write, void *data)
 {
@@ -2486,10 +2622,10 @@ static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
                 int val = *valp;
                 unsigned long lval;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         lval = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         lval = (unsigned long)val;
                 }
                 *lvalp = jiffies_to_clock_t(lval);
@@ -2497,7 +2633,7 @@ static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
         return 0;
 }
 
-static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
+static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
                                             int *valp,
                                             int write, void *data)
 {
@@ -2507,10 +2643,10 @@ static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
                 int val = *valp;
                 unsigned long lval;
                 if (val < 0) {
-                        *negp = -1;
+                        *negp = true;
                         lval = (unsigned long)-val;
                 } else {
-                        *negp = 0;
+                        *negp = false;
                         lval = (unsigned long)val;
                 }
                 *lvalp = jiffies_to_msecs(lval);
@@ -2607,6 +2743,157 @@ static int proc_do_cad_pid(struct ctl_table *table, int write,
         return 0;
 }
 
+/**
+ * proc_do_large_bitmap - read/write from/to a large bitmap
+ * @table: the sysctl table
+ * @write: %TRUE if this is a write to the sysctl file
+ * @buffer: the user buffer
+ * @lenp: the size of the user buffer
+ * @ppos: file position
+ *
+ * The bitmap is stored at table->data and the bitmap length (in bits)
+ * in table->maxlen.
+ *
+ * We use a range comma separated format (e.g. 1,3-4,10-10) so that
+ * large bitmaps may be represented in a compact manner. Writing into
+ * the file will clear the bitmap then update it with the given input.
+ *
+ * Returns 0 on success.
+ */
+int proc_do_large_bitmap(struct ctl_table *table, int write,
+                         void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+        int err = 0;
+        bool first = 1;
+        size_t left = *lenp;
+        unsigned long bitmap_len = table->maxlen;
+        unsigned long *bitmap = (unsigned long *) table->data;
+        unsigned long *tmp_bitmap = NULL;
+        char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
+
+        if (!bitmap_len || !left || (*ppos && !write)) {
+                *lenp = 0;
+                return 0;
+        }
+
+        if (write) {
+                unsigned long page = 0;
+                char *kbuf;
+
+                if (left > PAGE_SIZE - 1)
+                        left = PAGE_SIZE - 1;
+
+                page = __get_free_page(GFP_TEMPORARY);
+                kbuf = (char *) page;
+                if (!kbuf)
+                        return -ENOMEM;
+                if (copy_from_user(kbuf, buffer, left)) {
+                        free_page(page);
+                        return -EFAULT;
+                }
+                kbuf[left] = 0;
+
+                tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
+                                     GFP_KERNEL);
+                if (!tmp_bitmap) {
+                        free_page(page);
+                        return -ENOMEM;
+                }
+                proc_skip_char(&kbuf, &left, '\n');
+                while (!err && left) {
+                        unsigned long val_a, val_b;
+                        bool neg;
+
+                        err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
+                                             sizeof(tr_a), &c);
+                        if (err)
+                                break;
+                        if (val_a >= bitmap_len || neg) {
+                                err = -EINVAL;
+                                break;
+                        }
+
+                        val_b = val_a;
+                        if (left) {
+                                kbuf++;
+                                left--;
+                        }
+
+                        if (c == '-') {
+                                err = proc_get_long(&kbuf, &left, &val_b,
+                                                     &neg, tr_b, sizeof(tr_b),
+                                                     &c);
+                                if (err)
+                                        break;
+                                if (val_b >= bitmap_len || neg ||
+                                    val_a > val_b) {
+                                        err = -EINVAL;
+                                        break;
+                                }
+                                if (left) {
+                                        kbuf++;
+                                        left--;
+                                }
+                        }
+
+                        while (val_a <= val_b)
+                                set_bit(val_a++, tmp_bitmap);
+
+                        first = 0;
+                        proc_skip_char(&kbuf, &left, '\n');
+                }
+                free_page(page);
+        } else {
+                unsigned long bit_a, bit_b = 0;
+
+                while (left) {
+                        bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
+                        if (bit_a >= bitmap_len)
+                                break;
+                        bit_b = find_next_zero_bit(bitmap, bitmap_len,
+                                                   bit_a + 1) - 1;
+
+                        if (!first) {
+                                err = proc_put_char(&buffer, &left, ',');
+                                if (err)
+                                        break;
+                        }
+                        err = proc_put_long(&buffer, &left, bit_a, false);
+                        if (err)
+                                break;
+                        if (bit_a != bit_b) {
+                                err = proc_put_char(&buffer, &left, '-');
+                                if (err)
+                                        break;
+                                err = proc_put_long(&buffer, &left, bit_b, false);
+                                if (err)
+                                        break;
+                        }
+
+                        first = 0; bit_b++;
+                }
+                if (!err)
+                        err = proc_put_char(&buffer, &left, '\n');
+        }
+
+        if (!err) {
+                if (write) {
+                        if (*ppos)
+                                bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
+                        else
+                                memcpy(bitmap, tmp_bitmap,
+                                        BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
+                }
+                kfree(tmp_bitmap);
+                *lenp -= left;
+                *ppos += *lenp;
+                return 0;
+        } else {
+                kfree(tmp_bitmap);
+                return err;
+        }
+}
+
 #else /* CONFIG_PROC_FS */
 
 int proc_dostring(struct ctl_table *table, int write,
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index 59030570f5ca..1357c5786064 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -13,6 +13,7 @@
 #include <linux/file.h>
 #include <linux/ctype.h>
 #include <linux/netdevice.h>
+#include <linux/kernel.h>
 #include <linux/slab.h>
 
 #ifdef CONFIG_SYSCTL_SYSCALL
@@ -224,7 +225,6 @@ static const struct bin_table bin_net_ipv4_route_table[] = {
         { CTL_INT,      NET_IPV4_ROUTE_MTU_EXPIRES,             "mtu_expires" },
         { CTL_INT,      NET_IPV4_ROUTE_MIN_PMTU,                "min_pmtu" },
         { CTL_INT,      NET_IPV4_ROUTE_MIN_ADVMSS,              "min_adv_mss" },
-        { CTL_INT,      NET_IPV4_ROUTE_SECRET_INTERVAL,         "secret_interval" },
         {}
 };
 
@@ -1125,11 +1125,6 @@ out:
         return result;
 }
 
-static unsigned hex_value(int ch)
-{
-        return isdigit(ch) ? ch - '0' : ((ch | 0x20) - 'a') + 10;
-}
-
 static ssize_t bin_uuid(struct file *file,
         void __user *oldval, size_t oldlen, void __user *newval, size_t newlen)
 {
@@ -1157,7 +1152,8 @@ static ssize_t bin_uuid(struct file *file,
                         if (!isxdigit(str[0]) || !isxdigit(str[1]))
                                 goto out;
 
-                        uuid[i] = (hex_value(str[0]) << 4) | hex_value(str[1]);
+                        uuid[i] = (hex_to_bin(str[0]) << 4) |
+                                        hex_to_bin(str[1]);
                         str += 2;
                         if (*str == '-')
                                 str++;
diff --git a/kernel/time.c b/kernel/time.c
index 656dccfe1cbb..848b1c2ab09a 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -132,12 +132,11 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv,
  */
 static inline void warp_clock(void)
 {
-        write_seqlock_irq(&xtime_lock);
-        wall_to_monotonic.tv_sec -= sys_tz.tz_minuteswest * 60;
-        xtime.tv_sec += sys_tz.tz_minuteswest * 60;
-        update_xtime_cache(0);
-        write_sequnlock_irq(&xtime_lock);
-        clock_was_set();
+        struct timespec adjust;
+
+        adjust = current_kernel_time();
+        adjust.tv_sec += sys_tz.tz_minuteswest * 60;
+        do_settimeofday(&adjust);
 }
 
 /*
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 1f5dde637457..f08e99c1d561 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -625,6 +625,54 @@ static void clocksource_enqueue(struct clocksource *cs)
         list_add(&cs->list, entry);
 }
 
+
+/*
+ * Maximum time we expect to go between ticks. This includes idle
+ * tickless time. It provides the trade off between selecting a
+ * mult/shift pair that is very precise but can only handle a short
+ * period of time, vs. a mult/shift pair that can handle long periods
+ * of time but isn't as precise.
+ *
+ * This is a subsystem constant, and actual hardware limitations
+ * may override it (ie: clocksources that wrap every 3 seconds).
+ */
+#define MAX_UPDATE_LENGTH 5 /* Seconds */
+
+/**
+ * __clocksource_register_scale - Used to install new clocksources
+ * @t:          clocksource to be registered
+ * @scale:      Scale factor multiplied against freq to get clocksource hz
+ * @freq:       clocksource frequency (cycles per second) divided by scale
+ *
+ * Returns -EBUSY if registration fails, zero otherwise.
+ *
+ * This *SHOULD NOT* be called directly! Please use the
+ * clocksource_register_hz() or clocksource_register_khz helper functions.
+ */
+int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq)
+{
+
+        /*
+         * Ideally we want to use  some of the limits used in
+         * clocksource_max_deferment, to provide a more informed
+         * MAX_UPDATE_LENGTH. But for now this just gets the
+         * register interface working properly.
+         */
+        clocks_calc_mult_shift(&cs->mult, &cs->shift, freq,
+                                      NSEC_PER_SEC/scale,
+                                      MAX_UPDATE_LENGTH*scale);
+        cs->max_idle_ns = clocksource_max_deferment(cs);
+
+        mutex_lock(&clocksource_mutex);
+        clocksource_enqueue(cs);
+        clocksource_select();
+        clocksource_enqueue_watchdog(cs);
+        mutex_unlock(&clocksource_mutex);
+        return 0;
+}
+EXPORT_SYMBOL_GPL(__clocksource_register_scale);
+
+
 /**
  * clocksource_register - Used to install new clocksources
  * @t:          clocksource to be registered
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 7c0f180d6e9d..c63116863a80 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -69,7 +69,7 @@ static s64			time_freq;
 /* time at last adjustment (secs):                                      */
 static long                     time_reftime;
 
-long                            time_adjust;
+static long                     time_adjust;
 
 /* constant (boot-param configurable) NTP tick adjustment (upscaled)    */
 static s64                      ntp_tick_adj;
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index f992762d7f51..1d7b9bc1c034 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -150,14 +150,32 @@ static void tick_nohz_update_jiffies(ktime_t now)
         touch_softlockup_watchdog();
 }
 
+/*
+ * Updates the per cpu time idle statistics counters
+ */
+static void
+update_ts_time_stats(struct tick_sched *ts, ktime_t now, u64 *last_update_time)
+{
+        ktime_t delta;
+
+        if (ts->idle_active) {
+                delta = ktime_sub(now, ts->idle_entrytime);
+                ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta);
+                if (nr_iowait_cpu() > 0)
+                        ts->iowait_sleeptime = ktime_add(ts->iowait_sleeptime, delta);
+                ts->idle_entrytime = now;
+        }
+
+        if (last_update_time)
+                *last_update_time = ktime_to_us(now);
+
+}
+
 static void tick_nohz_stop_idle(int cpu, ktime_t now)
 {
         struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
-        ktime_t delta;
 
-        delta = ktime_sub(now, ts->idle_entrytime);
-        ts->idle_lastupdate = now;
-        ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta);
+        update_ts_time_stats(ts, now, NULL);
         ts->idle_active = 0;
 
         sched_clock_idle_wakeup_event(0);
@@ -165,20 +183,32 @@ static void tick_nohz_stop_idle(int cpu, ktime_t now)
 
 static ktime_t tick_nohz_start_idle(struct tick_sched *ts)
 {
-        ktime_t now, delta;
+        ktime_t now;
 
         now = ktime_get();
-        if (ts->idle_active) {
-                delta = ktime_sub(now, ts->idle_entrytime);
-                ts->idle_lastupdate = now;
-                ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta);
-        }
+
+        update_ts_time_stats(ts, now, NULL);
+
         ts->idle_entrytime = now;
         ts->idle_active = 1;
         sched_clock_idle_sleep_event();
         return now;
 }
 
+/**
+ * get_cpu_idle_time_us - get the total idle time of a cpu
+ * @cpu: CPU number to query
+ * @last_update_time: variable to store update time in
+ *
+ * Return the cummulative idle time (since boot) for a given
+ * CPU, in microseconds. The idle time returned includes
+ * the iowait time (unlike what "top" and co report).
+ *
+ * This time is measured via accounting rather than sampling,
+ * and is as accurate as ktime_get() is.
+ *
+ * This function returns -1 if NOHZ is not enabled.
+ */
 u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
 {
         struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
@@ -186,15 +216,38 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
         if (!tick_nohz_enabled)
                 return -1;
 
-        if (ts->idle_active)
-                *last_update_time = ktime_to_us(ts->idle_lastupdate);
-        else
-                *last_update_time = ktime_to_us(ktime_get());
+        update_ts_time_stats(ts, ktime_get(), last_update_time);
 
         return ktime_to_us(ts->idle_sleeptime);
 }
 EXPORT_SYMBOL_GPL(get_cpu_idle_time_us);
 
+/*
+ * get_cpu_iowait_time_us - get the total iowait time of a cpu
+ * @cpu: CPU number to query
+ * @last_update_time: variable to store update time in
+ *
+ * Return the cummulative iowait time (since boot) for a given
+ * CPU, in microseconds.
+ *
+ * This time is measured via accounting rather than sampling,
+ * and is as accurate as ktime_get() is.
+ *
+ * This function returns -1 if NOHZ is not enabled.
+ */
+u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time)
+{
+        struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
+
+        if (!tick_nohz_enabled)
+                return -1;
+
+        update_ts_time_stats(ts, ktime_get(), last_update_time);
+
+        return ktime_to_us(ts->iowait_sleeptime);
+}
+EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us);
+
 /**
  * tick_nohz_stop_sched_tick - stop the idle tick from the idle task
  *
@@ -262,6 +315,9 @@ void tick_nohz_stop_sched_tick(int inidle)
                 goto end;
         }
 
+        if (nohz_ratelimit(cpu))
+                goto end;
+
         ts->idle_calls++;
         /* Read jiffies and the time when jiffies were updated last */
         do {
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 39f6177fafac..caf8d4d4f5c8 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -165,13 +165,6 @@ struct timespec raw_time;
 /* flag for if timekeeping is suspended */
 int __read_mostly timekeeping_suspended;
 
-static struct timespec xtime_cache __attribute__ ((aligned (16)));
-void update_xtime_cache(u64 nsec)
-{
-        xtime_cache = xtime;
-        timespec_add_ns(&xtime_cache, nsec);
-}
-
 /* must hold xtime_lock */
 void timekeeping_leap_insert(int leapsecond)
 {
@@ -332,8 +325,6 @@ int do_settimeofday(struct timespec *tv)
 
         xtime = *tv;
 
-        update_xtime_cache(0);
-
         timekeeper.ntp_error = 0;
         ntp_clear();
 
@@ -559,7 +550,6 @@ void __init timekeeping_init(void)
         }
         set_normalized_timespec(&wall_to_monotonic,
                                 -boot.tv_sec, -boot.tv_nsec);
-        update_xtime_cache(0);
         total_sleep_time.tv_sec = 0;
         total_sleep_time.tv_nsec = 0;
         write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -593,7 +583,6 @@ static int timekeeping_resume(struct sys_device *dev)
                 wall_to_monotonic = timespec_sub(wall_to_monotonic, ts);
                 total_sleep_time = timespec_add_safe(total_sleep_time, ts);
         }
-        update_xtime_cache(0);
         /* re-base the last cycle value */
         timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
         timekeeper.ntp_error = 0;
@@ -788,7 +777,6 @@ void update_wall_time(void)
 {
         struct clocksource *clock;
         cycle_t offset;
-        u64 nsecs;
         int shift = 0, maxshift;
 
         /* Make sure we're fully resumed: */
@@ -847,7 +835,9 @@ void update_wall_time(void)
                 timekeeper.ntp_error += neg << timekeeper.ntp_error_shift;
         }
 
-        /* store full nanoseconds into xtime after rounding it up and
+
+        /*
+         * Store full nanoseconds into xtime after rounding it up and
          * add the remainder to the error difference.
          */
         xtime.tv_nsec = ((s64) timekeeper.xtime_nsec >> timekeeper.shift) + 1;
@@ -855,8 +845,15 @@ void update_wall_time(void)
         timekeeper.ntp_error += timekeeper.xtime_nsec <<
                                 timekeeper.ntp_error_shift;
 
-        nsecs = clocksource_cyc2ns(offset, timekeeper.mult, timekeeper.shift);
-        update_xtime_cache(nsecs);
+        /*
+         * Finally, make sure that after the rounding
+         * xtime.tv_nsec isn't larger then NSEC_PER_SEC
+         */
+        if (unlikely(xtime.tv_nsec >= NSEC_PER_SEC)) {
+                xtime.tv_nsec -= NSEC_PER_SEC;
+                xtime.tv_sec++;
+                second_overflow();
+        }
 
         /* check to see if there is a new clocksource to use */
         update_vsyscall(&xtime, timekeeper.clock, timekeeper.mult);
@@ -896,13 +893,13 @@ EXPORT_SYMBOL_GPL(monotonic_to_bootbased);
 
 unsigned long get_seconds(void)
 {
-        return xtime_cache.tv_sec;
+        return xtime.tv_sec;
 }
 EXPORT_SYMBOL(get_seconds);
 
 struct timespec __current_kernel_time(void)
 {
-        return xtime_cache;
+        return xtime;
 }
 
 struct timespec current_kernel_time(void)
@@ -913,7 +910,7 @@ struct timespec current_kernel_time(void)
         do {
                 seq = read_seqbegin(&xtime_lock);
 
-                now = xtime_cache;
+                now = xtime;
         } while (read_seqretry(&xtime_lock, seq));
 
         return now;
@@ -928,7 +925,7 @@ struct timespec get_monotonic_coarse(void)
         do {
                 seq = read_seqbegin(&xtime_lock);
 
-                now = xtime_cache;
+                now = xtime;
                 mono = wall_to_monotonic;
         } while (read_seqretry(&xtime_lock, seq));
 
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index 1a4a7dd78777..ab8f5e33fa92 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -176,6 +176,7 @@ static void print_cpu(struct seq_file *m, int cpu, u64 now)
                 P_ns(idle_waketime);
                 P_ns(idle_exittime);
                 P_ns(idle_sleeptime);
+                P_ns(iowait_sleeptime);
                 P(last_jiffies);
                 P(next_jiffies);
                 P_ns(idle_expires);
diff --git a/kernel/timer.c b/kernel/timer.c
index aeb6a54f2771..e3b8c697bde4 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -319,6 +319,24 @@ unsigned long round_jiffies_up_relative(unsigned long j)
 }
 EXPORT_SYMBOL_GPL(round_jiffies_up_relative);
 
+/**
+ * set_timer_slack - set the allowed slack for a timer
+ * @slack_hz: the amount of time (in jiffies) allowed for rounding
+ *
+ * Set the amount of time, in jiffies, that a certain timer has
+ * in terms of slack. By setting this value, the timer subsystem
+ * will schedule the actual timer somewhere between
+ * the time mod_timer() asks for, and that time plus the slack.
+ *
+ * By setting the slack to -1, a percentage of the delay is used
+ * instead.
+ */
+void set_timer_slack(struct timer_list *timer, int slack_hz)
+{
+        timer->slack = slack_hz;
+}
+EXPORT_SYMBOL_GPL(set_timer_slack);
+
 
 static inline void set_running_timer(struct tvec_base *base,
                                         struct timer_list *timer)
@@ -550,6 +568,7 @@ static void __init_timer(struct timer_list *timer,
 {
         timer->entry.next = NULL;
         timer->base = __raw_get_cpu_var(tvec_bases);
+        timer->slack = -1;
 #ifdef CONFIG_TIMER_STATS
         timer->start_site = NULL;
         timer->start_pid = -1;
@@ -715,6 +734,42 @@ int mod_timer_pending(struct timer_list *timer, unsigned long expires)
 }
 EXPORT_SYMBOL(mod_timer_pending);
 
+/*
+ * Decide where to put the timer while taking the slack into account
+ *
+ * Algorithm:
+ *   1) calculate the maximum (absolute) time
+ *   2) calculate the highest bit where the expires and new max are different
+ *   3) use this bit to make a mask
+ *   4) use the bitmask to round down the maximum time, so that all last
+ *      bits are zeros
+ */
+static inline
+unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
+{
+        unsigned long expires_limit, mask;
+        int bit;
+
+        expires_limit = expires;
+
+        if (timer->slack > -1)
+                expires_limit = expires + timer->slack;
+        else if (time_after(expires, jiffies)) /* auto slack: use 0.4% */
+                expires_limit = expires + (expires - jiffies)/256;
+
+        mask = expires ^ expires_limit;
+        if (mask == 0)
+                return expires;
+
+        bit = find_last_bit(&mask, BITS_PER_LONG);
+
+        mask = (1 << bit) - 1;
+
+        expires_limit = expires_limit & ~(mask);
+
+        return expires_limit;
+}
+
 /**
  * mod_timer - modify a timer's timeout
  * @timer: the timer to be modified
@@ -745,6 +800,8 @@ int mod_timer(struct timer_list *timer, unsigned long expires)
         if (timer_pending(timer) && timer->expires == expires)
                 return 1;
 
+        expires = apply_slack(timer, expires);
+
         return __mod_timer(timer, expires, false, TIMER_NOT_PINNED);
 }
 EXPORT_SYMBOL(mod_timer);
@@ -955,6 +1012,47 @@ static int cascade(struct tvec_base *base, struct tvec *tv, int index)
         return index;
 }
 
+static void call_timer_fn(struct timer_list *timer, void (*fn)(unsigned long),
+                          unsigned long data)
+{
+        int preempt_count = preempt_count();
+
+#ifdef CONFIG_LOCKDEP
+        /*
+         * It is permissible to free the timer from inside the
+         * function that is called from it, this we need to take into
+         * account for lockdep too. To avoid bogus "held lock freed"
+         * warnings as well as problems when looking into
+         * timer->lockdep_map, make a copy and use that here.
+         */
+        struct lockdep_map lockdep_map = timer->lockdep_map;
+#endif
+        /*
+         * Couple the lock chain with the lock chain at
+         * del_timer_sync() by acquiring the lock_map around the fn()
+         * call here and in del_timer_sync().
+         */
+        lock_map_acquire(&lockdep_map);
+
+        trace_timer_expire_entry(timer);
+        fn(data);
+        trace_timer_expire_exit(timer);
+
+        lock_map_release(&lockdep_map);
+
+        if (preempt_count != preempt_count()) {
+                WARN_ONCE(1, "timer: %pF preempt leak: %08x -> %08x\n",
+                          fn, preempt_count, preempt_count());
+                /*
+                 * Restore the preempt count. That gives us a decent
+                 * chance to survive and extract information. If the
+                 * callback kept a lock held, bad luck, but not worse
+                 * than the BUG() we had.
+                 */
+                preempt_count() = preempt_count;
+        }
+}
+
 #define INDEX(N) ((base->timer_jiffies >> (TVR_BITS + (N) * TVN_BITS)) & TVN_MASK)
 
 /**
@@ -998,45 +1096,7 @@ static inline void __run_timers(struct tvec_base *base)
                         detach_timer(timer, 1);
 
                         spin_unlock_irq(&base->lock);
-                        {
-                                int preempt_count = preempt_count();
-
-#ifdef CONFIG_LOCKDEP
-                                /*
-                                 * It is permissible to free the timer from
-                                 * inside the function that is called from
-                                 * it, this we need to take into account for
-                                 * lockdep too. To avoid bogus "held lock
-                                 * freed" warnings as well as problems when
-                                 * looking into timer->lockdep_map, make a
-                                 * copy and use that here.
-                                 */
-                                struct lockdep_map lockdep_map =
-                                        timer->lockdep_map;
-#endif
-                                /*
-                                 * Couple the lock chain with the lock chain at
-                                 * del_timer_sync() by acquiring the lock_map
-                                 * around the fn() call here and in
-                                 * del_timer_sync().
-                                 */
-                                lock_map_acquire(&lockdep_map);
-
-                                trace_timer_expire_entry(timer);
-                                fn(data);
-                                trace_timer_expire_exit(timer);
-
-                                lock_map_release(&lockdep_map);
-
-                                if (preempt_count != preempt_count()) {
-                                        printk(KERN_ERR "huh, entered %p "
-                                               "with preempt_count %08x, exited"
-                                               " with %08x?\n",
-                                               fn, preempt_count,
-                                               preempt_count());
-                                        BUG();
-                                }
-                        }
+                        call_timer_fn(timer, fn, data);
                         spin_lock_irq(&base->lock);
                 }
         }
@@ -1620,11 +1680,14 @@ static int __cpuinit timer_cpu_notify(struct notifier_block *self,
                                 unsigned long action, void *hcpu)
 {
         long cpu = (long)hcpu;
+        int err;
+
         switch(action) {
         case CPU_UP_PREPARE:
         case CPU_UP_PREPARE_FROZEN:
-                if (init_timers_cpu(cpu) < 0)
-                        return NOTIFY_BAD;
+                err = init_timers_cpu(cpu);
+                if (err < 0)
+                        return notifier_from_errno(err);
                 break;
 #ifdef CONFIG_HOTPLUG_CPU
         case CPU_DEAD:
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 13e13d428cd3..8b1797c4545b 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -44,9 +44,6 @@ config HAVE_FTRACE_MCOUNT_RECORD
         help
           See Documentation/trace/ftrace-design.txt
 
-config HAVE_HW_BRANCH_TRACER
-        bool
-
 config HAVE_SYSCALL_TRACEPOINTS
         bool
         help
@@ -374,14 +371,6 @@ config STACK_TRACER
 
           Say N if unsure.
 
-config HW_BRANCH_TRACER
-        depends on HAVE_HW_BRANCH_TRACER
-        bool "Trace hw branches"
-        select GENERIC_TRACER
-        help
-          This tracer records all branches on the system in a circular
-          buffer, giving access to the last N branches for each cpu.
-
 config KMEMTRACE
         bool "Trace SLAB allocations"
         select GENERIC_TRACER
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 78edc6490038..ffb1a5b0550e 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -41,7 +41,6 @@ obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
 obj-$(CONFIG_BOOT_TRACER) += trace_boot.o
 obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o
 obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o
-obj-$(CONFIG_HW_BRANCH_TRACER) += trace_hw_branches.o
 obj-$(CONFIG_KMEMTRACE) += kmemtrace.o
 obj-$(CONFIG_WORKQUEUE_TRACER) += trace_workqueue.o
 obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 2404b59b3097..32837e19e3bd 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -264,6 +264,7 @@ struct ftrace_profile {
         unsigned long                   counter;
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
         unsigned long long              time;
+        unsigned long long              time_squared;
 #endif
 };
 
@@ -366,9 +367,9 @@ static int function_stat_headers(struct seq_file *m)
 {
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
         seq_printf(m, "  Function                               "
-                   "Hit    Time            Avg\n"
+                   "Hit    Time            Avg             s^2\n"
                       "  --------                               "
-                   "---    ----            ---\n");
+                   "---    ----            ---             ---\n");
 #else
         seq_printf(m, "  Function                               Hit\n"
                       "  --------                               ---\n");
@@ -384,6 +385,7 @@ static int function_stat_show(struct seq_file *m, void *v)
         static DEFINE_MUTEX(mutex);
         static struct trace_seq s;
         unsigned long long avg;
+        unsigned long long stddev;
 #endif
 
         kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
@@ -394,11 +396,25 @@ static int function_stat_show(struct seq_file *m, void *v)
         avg = rec->time;
         do_div(avg, rec->counter);
 
+        /* Sample standard deviation (s^2) */
+        if (rec->counter <= 1)
+                stddev = 0;
+        else {
+                stddev = rec->time_squared - rec->counter * avg * avg;
+                /*
+                 * Divide only 1000 for ns^2 -> us^2 conversion.
+                 * trace_print_graph_duration will divide 1000 again.
+                 */
+                do_div(stddev, (rec->counter - 1) * 1000);
+        }
+
         mutex_lock(&mutex);
         trace_seq_init(&s);
         trace_print_graph_duration(rec->time, &s);
         trace_seq_puts(&s, "    ");
         trace_print_graph_duration(avg, &s);
+        trace_seq_puts(&s, "    ");
+        trace_print_graph_duration(stddev, &s);
         trace_print_seq(m, &s);
         mutex_unlock(&mutex);
 #endif
@@ -650,6 +666,10 @@ static void profile_graph_return(struct ftrace_graph_ret *trace)
         if (!stat->hash || !ftrace_profile_enabled)
                 goto out;
 
+        /* If the calltime was zero'd ignore it */
+        if (!trace->calltime)
+                goto out;
+
         calltime = trace->rettime - trace->calltime;
 
         if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) {
@@ -668,8 +688,10 @@ static void profile_graph_return(struct ftrace_graph_ret *trace)
         }
 
         rec = ftrace_find_profiled_func(stat, trace->func);
-        if (rec)
+        if (rec) {
                 rec->time += calltime;
+                rec->time_squared += calltime * calltime;
+        }
 
  out:
         local_irq_restore(flags);
@@ -3212,8 +3234,7 @@ free:
 }
 
 static void
-ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev,
-                                struct task_struct *next)
+ftrace_graph_probe_sched_switch(struct task_struct *prev, struct task_struct *next)
 {
         unsigned long long timestamp;
         int index;
@@ -3339,11 +3360,11 @@ void unregister_ftrace_graph(void)
                 goto out;
 
         ftrace_graph_active--;
-        unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
         ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
         ftrace_graph_entry = ftrace_graph_entry_stub;
         ftrace_shutdown(FTRACE_STOP_FUNC_RET);
         unregister_pm_notifier(&ftrace_suspend_notifier);
+        unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
 
  out:
         mutex_unlock(&ftrace_lock);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 41ca394feb22..7f6059c5aa94 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -319,6 +319,11 @@ EXPORT_SYMBOL_GPL(ring_buffer_event_data);
 #define TS_MASK         ((1ULL << TS_SHIFT) - 1)
 #define TS_DELTA_TEST   (~TS_MASK)
 
+/* Flag when events were overwritten */
+#define RB_MISSED_EVENTS        (1 << 31)
+/* Missed count stored at end */
+#define RB_MISSED_STORED        (1 << 30)
+
 struct buffer_data_page {
         u64              time_stamp;    /* page time stamp */
         local_t          commit;        /* write committed index */
@@ -338,6 +343,7 @@ struct buffer_page {
         local_t          write;         /* index for next write */
         unsigned         read;          /* index for next read */
         local_t          entries;       /* entries on this page */
+        unsigned long    real_end;      /* real end of data */
         struct buffer_data_page *page;  /* Actual data page */
 };
 
@@ -417,6 +423,12 @@ int ring_buffer_print_page_header(struct trace_seq *s)
                                (unsigned int)sizeof(field.commit),
                                (unsigned int)is_signed_type(long));
 
+        ret = trace_seq_printf(s, "\tfield: int overwrite;\t"
+                               "offset:%u;\tsize:%u;\tsigned:%u;\n",
+                               (unsigned int)offsetof(typeof(field), commit),
+                               1,
+                               (unsigned int)is_signed_type(long));
+
         ret = trace_seq_printf(s, "\tfield: char data;\t"
                                "offset:%u;\tsize:%u;\tsigned:%u;\n",
                                (unsigned int)offsetof(typeof(field), data),
@@ -440,6 +452,8 @@ struct ring_buffer_per_cpu {
         struct buffer_page              *tail_page;     /* write to tail */
         struct buffer_page              *commit_page;   /* committed pages */
         struct buffer_page              *reader_page;
+        unsigned long                   lost_events;
+        unsigned long                   last_overrun;
         local_t                         commit_overrun;
         local_t                         overrun;
         local_t                         entries;
@@ -1762,6 +1776,13 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
         kmemcheck_annotate_bitfield(event, bitfield);
 
         /*
+         * Save the original length to the meta data.
+         * This will be used by the reader to add lost event
+         * counter.
+         */
+        tail_page->real_end = tail;
+
+        /*
          * If this event is bigger than the minimum size, then
          * we need to be careful that we don't subtract the
          * write counter enough to allow another writer to slip
@@ -1979,17 +2000,13 @@ rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer,
                   u64 *ts, u64 *delta)
 {
         struct ring_buffer_event *event;
-        static int once;
         int ret;
 
-        if (unlikely(*delta > (1ULL << 59) && !once++)) {
-                printk(KERN_WARNING "Delta way too big! %llu"
-                       " ts=%llu write stamp = %llu\n",
-                       (unsigned long long)*delta,
-                       (unsigned long long)*ts,
-                       (unsigned long long)cpu_buffer->write_stamp);
-                WARN_ON(1);
-        }
+        WARN_ONCE(*delta > (1ULL << 59),
+                  KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n",
+                  (unsigned long long)*delta,
+                  (unsigned long long)*ts,
+                  (unsigned long long)cpu_buffer->write_stamp);
 
         /*
          * The delta is too big, we to add a
@@ -2838,6 +2855,7 @@ static struct buffer_page *
 rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
 {
         struct buffer_page *reader = NULL;
+        unsigned long overwrite;
         unsigned long flags;
         int nr_loops = 0;
         int ret;
@@ -2879,6 +2897,7 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
         local_set(&cpu_buffer->reader_page->write, 0);
         local_set(&cpu_buffer->reader_page->entries, 0);
         local_set(&cpu_buffer->reader_page->page->commit, 0);
+        cpu_buffer->reader_page->real_end = 0;
 
  spin:
         /*
@@ -2899,6 +2918,18 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
         rb_set_list_to_head(cpu_buffer, &cpu_buffer->reader_page->list);
 
         /*
+         * We want to make sure we read the overruns after we set up our
+         * pointers to the next object. The writer side does a
+         * cmpxchg to cross pages which acts as the mb on the writer
+         * side. Note, the reader will constantly fail the swap
+         * while the writer is updating the pointers, so this
+         * guarantees that the overwrite recorded here is the one we
+         * want to compare with the last_overrun.
+         */
+        smp_mb();
+        overwrite = local_read(&(cpu_buffer->overrun));
+
+        /*
          * Here's the tricky part.
          *
          * We need to move the pointer past the header page.
@@ -2929,6 +2960,11 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
         cpu_buffer->reader_page = reader;
         rb_reset_reader_page(cpu_buffer);
 
+        if (overwrite != cpu_buffer->last_overrun) {
+                cpu_buffer->lost_events = overwrite - cpu_buffer->last_overrun;
+                cpu_buffer->last_overrun = overwrite;
+        }
+
         goto again;
 
  out:
@@ -3005,8 +3041,14 @@ static void rb_advance_iter(struct ring_buffer_iter *iter)
                 rb_advance_iter(iter);
 }
 
+static int rb_lost_events(struct ring_buffer_per_cpu *cpu_buffer)
+{
+        return cpu_buffer->lost_events;
+}
+
 static struct ring_buffer_event *
-rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts)
+rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts,
+               unsigned long *lost_events)
 {
         struct ring_buffer_event *event;
         struct buffer_page *reader;
@@ -3058,6 +3100,8 @@ rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts)
                         ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
                                                          cpu_buffer->cpu, ts);
                 }
+                if (lost_events)
+                        *lost_events = rb_lost_events(cpu_buffer);
                 return event;
 
         default:
@@ -3168,12 +3212,14 @@ static inline int rb_ok_to_lock(void)
  * @buffer: The ring buffer to read
  * @cpu: The cpu to peak at
  * @ts: The timestamp counter of this event.
+ * @lost_events: a variable to store if events were lost (may be NULL)
  *
  * This will return the event that will be read next, but does
  * not consume the data.
  */
 struct ring_buffer_event *
-ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
+ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts,
+                 unsigned long *lost_events)
 {
         struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu];
         struct ring_buffer_event *event;
@@ -3188,7 +3234,7 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
         local_irq_save(flags);
         if (dolock)
                 spin_lock(&cpu_buffer->reader_lock);
-        event = rb_buffer_peek(cpu_buffer, ts);
+        event = rb_buffer_peek(cpu_buffer, ts, lost_events);
         if (event && event->type_len == RINGBUF_TYPE_PADDING)
                 rb_advance_reader(cpu_buffer);
         if (dolock)
@@ -3230,13 +3276,17 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
 /**
  * ring_buffer_consume - return an event and consume it
  * @buffer: The ring buffer to get the next event from
+ * @cpu: the cpu to read the buffer from
+ * @ts: a variable to store the timestamp (may be NULL)
+ * @lost_events: a variable to store if events were lost (may be NULL)
  *
  * Returns the next event in the ring buffer, and that event is consumed.
  * Meaning, that sequential reads will keep returning a different event,
  * and eventually empty the ring buffer if the producer is slower.
  */
 struct ring_buffer_event *
-ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
+ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts,
+                    unsigned long *lost_events)
 {
         struct ring_buffer_per_cpu *cpu_buffer;
         struct ring_buffer_event *event = NULL;
@@ -3257,9 +3307,11 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
         if (dolock)
                 spin_lock(&cpu_buffer->reader_lock);
 
-        event = rb_buffer_peek(cpu_buffer, ts);
-        if (event)
+        event = rb_buffer_peek(cpu_buffer, ts, lost_events);
+        if (event) {
+                cpu_buffer->lost_events = 0;
                 rb_advance_reader(cpu_buffer);
+        }
 
         if (dolock)
                 spin_unlock(&cpu_buffer->reader_lock);
@@ -3276,23 +3328,30 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
 EXPORT_SYMBOL_GPL(ring_buffer_consume);
 
 /**
- * ring_buffer_read_start - start a non consuming read of the buffer
+ * ring_buffer_read_prepare - Prepare for a non consuming read of the buffer
  * @buffer: The ring buffer to read from
  * @cpu: The cpu buffer to iterate over
  *
- * This starts up an iteration through the buffer. It also disables
- * the recording to the buffer until the reading is finished.
- * This prevents the reading from being corrupted. This is not
- * a consuming read, so a producer is not expected.
+ * This performs the initial preparations necessary to iterate
+ * through the buffer.  Memory is allocated, buffer recording
+ * is disabled, and the iterator pointer is returned to the caller.
  *
- * Must be paired with ring_buffer_finish.
+ * Disabling buffer recordng prevents the reading from being
+ * corrupted. This is not a consuming read, so a producer is not
+ * expected.
+ *
+ * After a sequence of ring_buffer_read_prepare calls, the user is
+ * expected to make at least one call to ring_buffer_prepare_sync.
+ * Afterwards, ring_buffer_read_start is invoked to get things going
+ * for real.
+ *
+ * This overall must be paired with ring_buffer_finish.
  */
 struct ring_buffer_iter *
-ring_buffer_read_start(struct ring_buffer *buffer, int cpu)
+ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu)
 {
         struct ring_buffer_per_cpu *cpu_buffer;
         struct ring_buffer_iter *iter;
-        unsigned long flags;
 
         if (!cpumask_test_cpu(cpu, buffer->cpumask))
                 return NULL;
@@ -3306,15 +3365,52 @@ ring_buffer_read_start(struct ring_buffer *buffer, int cpu)
         iter->cpu_buffer = cpu_buffer;
 
         atomic_inc(&cpu_buffer->record_disabled);
+
+        return iter;
+}
+EXPORT_SYMBOL_GPL(ring_buffer_read_prepare);
+
+/**
+ * ring_buffer_read_prepare_sync - Synchronize a set of prepare calls
+ *
+ * All previously invoked ring_buffer_read_prepare calls to prepare
+ * iterators will be synchronized.  Afterwards, read_buffer_read_start
+ * calls on those iterators are allowed.
+ */
+void
+ring_buffer_read_prepare_sync(void)
+{
         synchronize_sched();
+}
+EXPORT_SYMBOL_GPL(ring_buffer_read_prepare_sync);
+
+/**
+ * ring_buffer_read_start - start a non consuming read of the buffer
+ * @iter: The iterator returned by ring_buffer_read_prepare
+ *
+ * This finalizes the startup of an iteration through the buffer.
+ * The iterator comes from a call to ring_buffer_read_prepare and
+ * an intervening ring_buffer_read_prepare_sync must have been
+ * performed.
+ *
+ * Must be paired with ring_buffer_finish.
+ */
+void
+ring_buffer_read_start(struct ring_buffer_iter *iter)
+{
+        struct ring_buffer_per_cpu *cpu_buffer;
+        unsigned long flags;
+
+        if (!iter)
+                return;
+
+        cpu_buffer = iter->cpu_buffer;
 
         spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
         arch_spin_lock(&cpu_buffer->lock);
         rb_iter_reset(iter);
         arch_spin_unlock(&cpu_buffer->lock);
         spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
-
-        return iter;
 }
 EXPORT_SYMBOL_GPL(ring_buffer_read_start);
 
@@ -3408,6 +3504,9 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
         cpu_buffer->write_stamp = 0;
         cpu_buffer->read_stamp = 0;
 
+        cpu_buffer->lost_events = 0;
+        cpu_buffer->last_overrun = 0;
+
         rb_head_page_activate(cpu_buffer);
 }
 
@@ -3683,6 +3782,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
         struct ring_buffer_event *event;
         struct buffer_data_page *bpage;
         struct buffer_page *reader;
+        unsigned long missed_events;
         unsigned long flags;
         unsigned int commit;
         unsigned int read;
@@ -3719,6 +3819,9 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
         read = reader->read;
         commit = rb_page_commit(reader);
 
+        /* Check if any events were dropped */
+        missed_events = cpu_buffer->lost_events;
+
         /*
          * If this page has been partially read or
          * if len is not big enough to read the rest of the page or
@@ -3779,9 +3882,35 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
                 local_set(&reader->entries, 0);
                 reader->read = 0;
                 *data_page = bpage;
+
+                /*
+                 * Use the real_end for the data size,
+                 * This gives us a chance to store the lost events
+                 * on the page.
+                 */
+                if (reader->real_end)
+                        local_set(&bpage->commit, reader->real_end);
         }
         ret = read;
 
+        cpu_buffer->lost_events = 0;
+        /*
+         * Set a flag in the commit field if we lost events
+         */
+        if (missed_events) {
+                commit = local_read(&bpage->commit);
+
+                /* If there is room at the end of the page to save the
+                 * missed events, then record it there.
+                 */
+                if (BUF_PAGE_SIZE - commit >= sizeof(missed_events)) {
+                        memcpy(&bpage->data[commit], &missed_events,
+                               sizeof(missed_events));
+                        local_add(RB_MISSED_STORED, &bpage->commit);
+                }
+                local_add(RB_MISSED_EVENTS, &bpage->commit);
+        }
+
  out_unlock:
         spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
 
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index df74c7982255..302f8a614635 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -81,7 +81,7 @@ static enum event_status read_event(int cpu)
         int *entry;
         u64 ts;
 
-        event = ring_buffer_consume(buffer, cpu, &ts);
+        event = ring_buffer_consume(buffer, cpu, &ts, NULL);
         if (!event)
                 return EVENT_DROPPED;
 
@@ -113,7 +113,8 @@ static enum event_status read_page(int cpu)
         ret = ring_buffer_read_page(buffer, &bpage, PAGE_SIZE, cpu, 1);
         if (ret >= 0) {
                 rpage = bpage;
-                commit = local_read(&rpage->commit);
+                /* The commit may have missed event flags set, clear them */
+                commit = local_read(&rpage->commit) & 0xfffff;
                 for (i = 0; i < commit && !kill_test; i += inc) {
 
                         if (i >= (PAGE_SIZE - offsetof(struct rb_page, data))) {
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 44f916a04065..8a76339a9e65 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -117,9 +117,12 @@ static cpumask_var_t __read_mostly	tracing_buffer_mask;
  *
  * It is default off, but you can enable it with either specifying
  * "ftrace_dump_on_oops" in the kernel command line, or setting
- * /proc/sys/kernel/ftrace_dump_on_oops to true.
+ * /proc/sys/kernel/ftrace_dump_on_oops
+ * Set 1 if you want to dump buffers of all CPUs
+ * Set 2 if you want to dump the buffer of the CPU that triggered oops
  */
-int ftrace_dump_on_oops;
+
+enum ftrace_dump_mode ftrace_dump_on_oops;
 
 static int tracing_set_tracer(const char *buf);
 
@@ -139,8 +142,17 @@ __setup("ftrace=", set_cmdline_ftrace);
 
 static int __init set_ftrace_dump_on_oops(char *str)
 {
-        ftrace_dump_on_oops = 1;
-        return 1;
+        if (*str++ != '=' || !*str) {
+                ftrace_dump_on_oops = DUMP_ALL;
+                return 1;
+        }
+
+        if (!strcmp("orig_cpu", str)) {
+                ftrace_dump_on_oops = DUMP_ORIG;
+                return 1;
+        }
+
+        return 0;
 }
 __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops);
 
@@ -1545,7 +1557,8 @@ static void trace_iterator_increment(struct trace_iterator *iter)
 }
 
 static struct trace_entry *
-peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
+peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts,
+                unsigned long *lost_events)
 {
         struct ring_buffer_event *event;
         struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu];
@@ -1556,7 +1569,8 @@ peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
         if (buf_iter)
                 event = ring_buffer_iter_peek(buf_iter, ts);
         else
-                event = ring_buffer_peek(iter->tr->buffer, cpu, ts);
+                event = ring_buffer_peek(iter->tr->buffer, cpu, ts,
+                                         lost_events);
 
         ftrace_enable_cpu();
 
@@ -1564,10 +1578,12 @@ peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
 }
 
 static struct trace_entry *
-__find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
+__find_next_entry(struct trace_iterator *iter, int *ent_cpu,
+                  unsigned long *missing_events, u64 *ent_ts)
 {
         struct ring_buffer *buffer = iter->tr->buffer;
         struct trace_entry *ent, *next = NULL;
+        unsigned long lost_events = 0, next_lost = 0;
         int cpu_file = iter->cpu_file;
         u64 next_ts = 0, ts;
         int next_cpu = -1;
@@ -1580,7 +1596,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
         if (cpu_file > TRACE_PIPE_ALL_CPU) {
                 if (ring_buffer_empty_cpu(buffer, cpu_file))
                         return NULL;
-                ent = peek_next_entry(iter, cpu_file, ent_ts);
+                ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events);
                 if (ent_cpu)
                         *ent_cpu = cpu_file;
 
@@ -1592,7 +1608,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
                 if (ring_buffer_empty_cpu(buffer, cpu))
                         continue;
 
-                ent = peek_next_entry(iter, cpu, &ts);
+                ent = peek_next_entry(iter, cpu, &ts, &lost_events);
 
                 /*
                  * Pick the entry with the smallest timestamp:
@@ -1601,6 +1617,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
                         next = ent;
                         next_cpu = cpu;
                         next_ts = ts;
+                        next_lost = lost_events;
                 }
         }
 
@@ -1610,6 +1627,9 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
         if (ent_ts)
                 *ent_ts = next_ts;
 
+        if (missing_events)
+                *missing_events = next_lost;
+
         return next;
 }
 
@@ -1617,13 +1637,14 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
                                           int *ent_cpu, u64 *ent_ts)
 {
-        return __find_next_entry(iter, ent_cpu, ent_ts);
+        return __find_next_entry(iter, ent_cpu, NULL, ent_ts);
 }
 
 /* Find the next real entry, and increment the iterator to the next entry */
 static void *find_next_entry_inc(struct trace_iterator *iter)
 {
-        iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts);
+        iter->ent = __find_next_entry(iter, &iter->cpu,
+                                      &iter->lost_events, &iter->ts);
 
         if (iter->ent)
                 trace_iterator_increment(iter);
@@ -1635,7 +1656,8 @@ static void trace_consume(struct trace_iterator *iter)
 {
         /* Don't allow ftrace to trace into the ring buffers */
         ftrace_disable_cpu();
-        ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts);
+        ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts,
+                            &iter->lost_events);
         ftrace_enable_cpu();
 }
 
@@ -1786,7 +1808,7 @@ static void print_func_help_header(struct seq_file *m)
 }
 
 
-static void
+void
 print_trace_header(struct seq_file *m, struct trace_iterator *iter)
 {
         unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
@@ -1995,7 +2017,7 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
         return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
 }
 
-static int trace_empty(struct trace_iterator *iter)
+int trace_empty(struct trace_iterator *iter)
 {
         int cpu;
 
@@ -2030,6 +2052,10 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter)
 {
         enum print_line_t ret;
 
+        if (iter->lost_events)
+                trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
+                                 iter->cpu, iter->lost_events);
+
         if (iter->trace && iter->trace->print_line) {
                 ret = iter->trace->print_line(iter);
                 if (ret != TRACE_TYPE_UNHANDLED)
@@ -2058,6 +2084,23 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter)
         return print_trace_fmt(iter);
 }
 
+void trace_default_header(struct seq_file *m)
+{
+        struct trace_iterator *iter = m->private;
+
+        if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
+                /* print nothing if the buffers are empty */
+                if (trace_empty(iter))
+                        return;
+                print_trace_header(m, iter);
+                if (!(trace_flags & TRACE_ITER_VERBOSE))
+                        print_lat_help_header(m);
+        } else {
+                if (!(trace_flags & TRACE_ITER_VERBOSE))
+                        print_func_help_header(m);
+        }
+}
+
 static int s_show(struct seq_file *m, void *v)
 {
         struct trace_iterator *iter = v;
@@ -2070,17 +2113,9 @@ static int s_show(struct seq_file *m, void *v)
                 }
                 if (iter->trace && iter->trace->print_header)
                         iter->trace->print_header(m);
-                else if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
-                        /* print nothing if the buffers are empty */
-                        if (trace_empty(iter))
-                                return 0;
-                        print_trace_header(m, iter);
-                        if (!(trace_flags & TRACE_ITER_VERBOSE))
-                                print_lat_help_header(m);
-                } else {
-                        if (!(trace_flags & TRACE_ITER_VERBOSE))
-                                print_func_help_header(m);
-                }
+                else
+                        trace_default_header(m);
+
         } else if (iter->leftover) {
                 /*
                  * If we filled the seq_file buffer earlier, we
@@ -2166,15 +2201,20 @@ __tracing_open(struct inode *inode, struct file *file)
 
         if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
                 for_each_tracing_cpu(cpu) {
-
                         iter->buffer_iter[cpu] =
-                                ring_buffer_read_start(iter->tr->buffer, cpu);
+                                ring_buffer_read_prepare(iter->tr->buffer, cpu);
+                }
+                ring_buffer_read_prepare_sync();
+                for_each_tracing_cpu(cpu) {
+                        ring_buffer_read_start(iter->buffer_iter[cpu]);
                         tracing_iter_reset(iter, cpu);
                 }
         } else {
                 cpu = iter->cpu_file;
                 iter->buffer_iter[cpu] =
-                                ring_buffer_read_start(iter->tr->buffer, cpu);
+                        ring_buffer_read_prepare(iter->tr->buffer, cpu);
+                ring_buffer_read_prepare_sync();
+                ring_buffer_read_start(iter->buffer_iter[cpu]);
                 tracing_iter_reset(iter, cpu);
         }
 
@@ -3269,12 +3309,12 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
                                         size_t len,
                                         unsigned int flags)
 {
-        struct page *pages[PIPE_BUFFERS];
-        struct partial_page partial[PIPE_BUFFERS];
+        struct page *pages_def[PIPE_DEF_BUFFERS];
+        struct partial_page partial_def[PIPE_DEF_BUFFERS];
         struct trace_iterator *iter = filp->private_data;
         struct splice_pipe_desc spd = {
-                .pages          = pages,
-                .partial        = partial,
+                .pages          = pages_def,
+                .partial        = partial_def,
                 .nr_pages       = 0, /* This gets updated below. */
                 .flags          = flags,
                 .ops            = &tracing_pipe_buf_ops,
@@ -3285,6 +3325,9 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
         size_t rem;
         unsigned int i;
 
+        if (splice_grow_spd(pipe, &spd))
+                return -ENOMEM;
+
         /* copy the tracer to avoid using a global lock all around */
         mutex_lock(&trace_types_lock);
         if (unlikely(old_tracer != current_trace && current_trace)) {
@@ -3315,23 +3358,23 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
         trace_access_lock(iter->cpu_file);
 
         /* Fill as many pages as possible. */
-        for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) {
-                pages[i] = alloc_page(GFP_KERNEL);
-                if (!pages[i])
+        for (i = 0, rem = len; i < pipe->buffers && rem; i++) {
+                spd.pages[i] = alloc_page(GFP_KERNEL);
+                if (!spd.pages[i])
                         break;
 
                 rem = tracing_fill_pipe_page(rem, iter);
 
                 /* Copy the data into the page, so we can start over. */
                 ret = trace_seq_to_buffer(&iter->seq,
-                                          page_address(pages[i]),
+                                          page_address(spd.pages[i]),
                                           iter->seq.len);
                 if (ret < 0) {
-                        __free_page(pages[i]);
+                        __free_page(spd.pages[i]);
                         break;
                 }
-                partial[i].offset = 0;
-                partial[i].len = iter->seq.len;
+                spd.partial[i].offset = 0;
+                spd.partial[i].len = iter->seq.len;
 
                 trace_seq_init(&iter->seq);
         }
@@ -3342,12 +3385,14 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 
         spd.nr_pages = i;
 
-        return splice_to_pipe(pipe, &spd);
+        ret = splice_to_pipe(pipe, &spd);
+out:
+        splice_shrink_spd(pipe, &spd);
+        return ret;
 
 out_err:
         mutex_unlock(&iter->mutex);
-
-        return ret;
+        goto out;
 }
 
 static ssize_t
@@ -3746,11 +3791,11 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                             unsigned int flags)
 {
         struct ftrace_buffer_info *info = file->private_data;
-        struct partial_page partial[PIPE_BUFFERS];
-        struct page *pages[PIPE_BUFFERS];
+        struct partial_page partial_def[PIPE_DEF_BUFFERS];
+        struct page *pages_def[PIPE_DEF_BUFFERS];
         struct splice_pipe_desc spd = {
-                .pages          = pages,
-                .partial        = partial,
+                .pages          = pages_def,
+                .partial        = partial_def,
                 .flags          = flags,
                 .ops            = &buffer_pipe_buf_ops,
                 .spd_release    = buffer_spd_release,
@@ -3759,22 +3804,28 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
         int entries, size, i;
         size_t ret;
 
+        if (splice_grow_spd(pipe, &spd))
+                return -ENOMEM;
+
         if (*ppos & (PAGE_SIZE - 1)) {
                 WARN_ONCE(1, "Ftrace: previous read must page-align\n");
-                return -EINVAL;
+                ret = -EINVAL;
+                goto out;
         }
 
         if (len & (PAGE_SIZE - 1)) {
                 WARN_ONCE(1, "Ftrace: splice_read should page-align\n");
-                if (len < PAGE_SIZE)
-                        return -EINVAL;
+                if (len < PAGE_SIZE) {
+                        ret = -EINVAL;
+                        goto out;
+                }
                 len &= PAGE_MASK;
         }
 
         trace_access_lock(info->cpu);
         entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
 
-        for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) {
+        for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) {
                 struct page *page;
                 int r;
 
@@ -3829,11 +3880,12 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                 else
                         ret = 0;
                 /* TODO: block */
-                return ret;
+                goto out;
         }
 
         ret = splice_to_pipe(pipe, &spd);
-
+        splice_shrink_spd(pipe, &spd);
+out:
         return ret;
 }
 
@@ -4324,7 +4376,7 @@ static int trace_panic_handler(struct notifier_block *this,
                                unsigned long event, void *unused)
 {
         if (ftrace_dump_on_oops)
-                ftrace_dump();
+                ftrace_dump(ftrace_dump_on_oops);
         return NOTIFY_OK;
 }
 
@@ -4341,7 +4393,7 @@ static int trace_die_handler(struct notifier_block *self,
         switch (val) {
         case DIE_OOPS:
                 if (ftrace_dump_on_oops)
-                        ftrace_dump();
+                        ftrace_dump(ftrace_dump_on_oops);
                 break;
         default:
                 break;
@@ -4382,7 +4434,8 @@ trace_printk_seq(struct trace_seq *s)
         trace_seq_init(s);
 }
 
-static void __ftrace_dump(bool disable_tracing)
+static void
+__ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
 {
         static arch_spinlock_t ftrace_dump_lock =
                 (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
@@ -4415,12 +4468,25 @@ static void __ftrace_dump(bool disable_tracing)
         /* don't look at user memory in panic mode */
         trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
 
-        printk(KERN_TRACE "Dumping ftrace buffer:\n");
-
         /* Simulate the iterator */
         iter.tr = &global_trace;
         iter.trace = current_trace;
-        iter.cpu_file = TRACE_PIPE_ALL_CPU;
+
+        switch (oops_dump_mode) {
+        case DUMP_ALL:
+                iter.cpu_file = TRACE_PIPE_ALL_CPU;
+                break;
+        case DUMP_ORIG:
+                iter.cpu_file = raw_smp_processor_id();
+                break;
+        case DUMP_NONE:
+                goto out_enable;
+        default:
+                printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n");
+                iter.cpu_file = TRACE_PIPE_ALL_CPU;
+        }
+
+        printk(KERN_TRACE "Dumping ftrace buffer:\n");
 
         /*
          * We need to stop all tracing on all CPUS to read the
@@ -4459,6 +4525,7 @@ static void __ftrace_dump(bool disable_tracing)
         else
                 printk(KERN_TRACE "---------------------------------\n");
 
+ out_enable:
         /* Re-enable tracing if requested */
         if (!disable_tracing) {
                 trace_flags |= old_userobj;
@@ -4475,9 +4542,9 @@ static void __ftrace_dump(bool disable_tracing)
 }
 
 /* By default: disable tracing after the dump */
-void ftrace_dump(void)
+void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
 {
-        __ftrace_dump(true);
+        __ftrace_dump(true, oops_dump_mode);
 }
 
 __init static int tracer_alloc_buffers(void)
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 2825ef2c0b15..d1ce0bec1b3f 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -34,7 +34,6 @@ enum trace_type {
         TRACE_GRAPH_RET,
         TRACE_GRAPH_ENT,
         TRACE_USER_STACK,
-        TRACE_HW_BRANCHES,
         TRACE_KMEM_ALLOC,
         TRACE_KMEM_FREE,
         TRACE_BLK,
@@ -103,29 +102,17 @@ struct syscall_trace_exit {
         long                    ret;
 };
 
-struct kprobe_trace_entry {
+struct kprobe_trace_entry_head {
         struct trace_entry      ent;
         unsigned long           ip;
-        int                     nargs;
-        unsigned long           args[];
 };
 
-#define SIZEOF_KPROBE_TRACE_ENTRY(n)                    \
-        (offsetof(struct kprobe_trace_entry, args) +    \
-        (sizeof(unsigned long) * (n)))
-
-struct kretprobe_trace_entry {
+struct kretprobe_trace_entry_head {
         struct trace_entry      ent;
         unsigned long           func;
         unsigned long           ret_ip;
-        int                     nargs;
-        unsigned long           args[];
 };
 
-#define SIZEOF_KRETPROBE_TRACE_ENTRY(n)                 \
-        (offsetof(struct kretprobe_trace_entry, args) + \
-        (sizeof(unsigned long) * (n)))
-
 /*
  * trace_flag_type is an enumeration that holds different
  * states when a trace occurs. These are:
@@ -229,7 +216,6 @@ extern void __ftrace_bad_type(void);
                           TRACE_GRAPH_ENT);             \
                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
                           TRACE_GRAPH_RET);             \
-                IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
                           TRACE_KMEM_ALLOC);    \
                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
@@ -378,6 +364,9 @@ void trace_function(struct trace_array *tr,
                     unsigned long ip,
                     unsigned long parent_ip,
                     unsigned long flags, int pc);
+void trace_default_header(struct seq_file *m);
+void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
+int trace_empty(struct trace_iterator *iter);
 
 void trace_graph_return(struct ftrace_graph_ret *trace);
 int trace_graph_entry(struct ftrace_graph_ent *trace);
@@ -467,8 +456,6 @@ extern int trace_selftest_startup_sysprof(struct tracer *trace,
                                                struct trace_array *tr);
 extern int trace_selftest_startup_branch(struct tracer *trace,
                                          struct trace_array *tr);
-extern int trace_selftest_startup_hw_branches(struct tracer *trace,
-                                              struct trace_array *tr);
 extern int trace_selftest_startup_ksym(struct tracer *trace,
                                          struct trace_array *tr);
 #endif /* CONFIG_FTRACE_STARTUP_TEST */
@@ -491,9 +478,29 @@ extern int trace_clock_id;
 
 /* Standard output formatting function used for function return traces */
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-extern enum print_line_t print_graph_function(struct trace_iterator *iter);
+
+/* Flag options */
+#define TRACE_GRAPH_PRINT_OVERRUN       0x1
+#define TRACE_GRAPH_PRINT_CPU           0x2
+#define TRACE_GRAPH_PRINT_OVERHEAD      0x4
+#define TRACE_GRAPH_PRINT_PROC          0x8
+#define TRACE_GRAPH_PRINT_DURATION      0x10
+#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
+
+extern enum print_line_t
+print_graph_function_flags(struct trace_iterator *iter, u32 flags);
+extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 extern enum print_line_t
 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
+extern void graph_trace_open(struct trace_iterator *iter);
+extern void graph_trace_close(struct trace_iterator *iter);
+extern int __trace_graph_entry(struct trace_array *tr,
+                               struct ftrace_graph_ent *trace,
+                               unsigned long flags, int pc);
+extern void __trace_graph_return(struct trace_array *tr,
+                                 struct ftrace_graph_ret *trace,
+                                 unsigned long flags, int pc);
+
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 /* TODO: make this variable */
@@ -524,7 +531,7 @@ static inline int ftrace_graph_addr(unsigned long addr)
 #endif /* CONFIG_DYNAMIC_FTRACE */
 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
 static inline enum print_line_t
-print_graph_function(struct trace_iterator *iter)
+print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 {
         return TRACE_TYPE_UNHANDLED;
 }
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index c16a08f399df..dc008c1240da 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -318,18 +318,6 @@ FTRACE_ENTRY(branch, trace_branch,
                  __entry->func, __entry->file, __entry->correct)
 );
 
-FTRACE_ENTRY(hw_branch, hw_branch_entry,
-
-        TRACE_HW_BRANCHES,
-
-        F_STRUCT(
-                __field(        u64,    from    )
-                __field(        u64,    to      )
-        ),
-
-        F_printk("from: %llx to: %llx", __entry->from, __entry->to)
-);
-
 FTRACE_ENTRY(kmem_alloc, kmemtrace_alloc_entry,
 
         TRACE_KMEM_ALLOC,
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 88c0b6dbd7fe..58092d844a1f 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1398,7 +1398,7 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
         }
 
         err = -EINVAL;
-        if (!call)
+        if (&call->list == &ftrace_events)
                 goto out_unlock;
 
         err = -EEXIST;
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 9aed1a5cf553..dd11c830eb84 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -40,7 +40,7 @@ struct fgraph_data {
 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 #define TRACE_GRAPH_PRINT_PROC          0x8
 #define TRACE_GRAPH_PRINT_DURATION      0x10
-#define TRACE_GRAPH_PRINT_ABS_TIME      0X20
+#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 
 static struct tracer_opt trace_opts[] = {
         /* Display overruns? (for self-debug purpose) */
@@ -179,7 +179,7 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
         return ret;
 }
 
-static int __trace_graph_entry(struct trace_array *tr,
+int __trace_graph_entry(struct trace_array *tr,
                                 struct ftrace_graph_ent *trace,
                                 unsigned long flags,
                                 int pc)
@@ -246,7 +246,7 @@ int trace_graph_thresh_entry(struct ftrace_graph_ent *trace)
                 return trace_graph_entry(trace);
 }
 
-static void __trace_graph_return(struct trace_array *tr,
+void __trace_graph_return(struct trace_array *tr,
                                 struct ftrace_graph_ret *trace,
                                 unsigned long flags,
                                 int pc)
@@ -490,9 +490,10 @@ get_return_for_leaf(struct trace_iterator *iter,
                          * We need to consume the current entry to see
                          * the next one.
                          */
-                        ring_buffer_consume(iter->tr->buffer, iter->cpu, NULL);
+                        ring_buffer_consume(iter->tr->buffer, iter->cpu,
+                                            NULL, NULL);
                         event = ring_buffer_peek(iter->tr->buffer, iter->cpu,
-                                                 NULL);
+                                                 NULL, NULL);
                 }
 
                 if (!event)
@@ -526,17 +527,18 @@ get_return_for_leaf(struct trace_iterator *iter,
 
 /* Signal a overhead of time execution to the output */
 static int
-print_graph_overhead(unsigned long long duration, struct trace_seq *s)
+print_graph_overhead(unsigned long long duration, struct trace_seq *s,
+                     u32 flags)
 {
         /* If duration disappear, we don't need anything */
-        if (!(tracer_flags.val & TRACE_GRAPH_PRINT_DURATION))
+        if (!(flags & TRACE_GRAPH_PRINT_DURATION))
                 return 1;
 
         /* Non nested entry or return */
         if (duration == -1)
                 return trace_seq_printf(s, "  ");
 
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+        if (flags & TRACE_GRAPH_PRINT_OVERHEAD) {
                 /* Duration exceeded 100 msecs */
                 if (duration > 100000ULL)
                         return trace_seq_printf(s, "! ");
@@ -562,7 +564,7 @@ static int print_graph_abs_time(u64 t, struct trace_seq *s)
 
 static enum print_line_t
 print_graph_irq(struct trace_iterator *iter, unsigned long addr,
-                enum trace_type type, int cpu, pid_t pid)
+                enum trace_type type, int cpu, pid_t pid, u32 flags)
 {
         int ret;
         struct trace_seq *s = &iter->seq;
@@ -572,21 +574,21 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
                 return TRACE_TYPE_UNHANDLED;
 
         /* Absolute time */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) {
+        if (flags & TRACE_GRAPH_PRINT_ABS_TIME) {
                 ret = print_graph_abs_time(iter->ts, s);
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
 
         /* Cpu */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+        if (flags & TRACE_GRAPH_PRINT_CPU) {
                 ret = print_graph_cpu(s, cpu);
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
 
         /* Proc */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
+        if (flags & TRACE_GRAPH_PRINT_PROC) {
                 ret = print_graph_proc(s, pid);
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
@@ -596,7 +598,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
         }
 
         /* No overhead */
-        ret = print_graph_overhead(-1, s);
+        ret = print_graph_overhead(-1, s, flags);
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
@@ -609,7 +611,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* Don't close the duration column if haven't one */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
+        if (flags & TRACE_GRAPH_PRINT_DURATION)
                 trace_seq_printf(s, " |");
         ret = trace_seq_printf(s, "\n");
 
@@ -679,7 +681,8 @@ print_graph_duration(unsigned long long duration, struct trace_seq *s)
 static enum print_line_t
 print_graph_entry_leaf(struct trace_iterator *iter,
                 struct ftrace_graph_ent_entry *entry,
-                struct ftrace_graph_ret_entry *ret_entry, struct trace_seq *s)
+                struct ftrace_graph_ret_entry *ret_entry,
+                struct trace_seq *s, u32 flags)
 {
         struct fgraph_data *data = iter->private;
         struct ftrace_graph_ret *graph_ret;
@@ -711,12 +714,12 @@ print_graph_entry_leaf(struct trace_iterator *iter,
         }
 
         /* Overhead */
-        ret = print_graph_overhead(duration, s);
+        ret = print_graph_overhead(duration, s, flags);
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* Duration */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
+        if (flags & TRACE_GRAPH_PRINT_DURATION) {
                 ret = print_graph_duration(duration, s);
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
@@ -739,7 +742,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
 static enum print_line_t
 print_graph_entry_nested(struct trace_iterator *iter,
                          struct ftrace_graph_ent_entry *entry,
-                         struct trace_seq *s, int cpu)
+                         struct trace_seq *s, int cpu, u32 flags)
 {
         struct ftrace_graph_ent *call = &entry->graph_ent;
         struct fgraph_data *data = iter->private;
@@ -759,12 +762,12 @@ print_graph_entry_nested(struct trace_iterator *iter,
         }
 
         /* No overhead */
-        ret = print_graph_overhead(-1, s);
+        ret = print_graph_overhead(-1, s, flags);
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* No time */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
+        if (flags & TRACE_GRAPH_PRINT_DURATION) {
                 ret = trace_seq_printf(s, "            |  ");
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
@@ -790,7 +793,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
 
 static enum print_line_t
 print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
-                     int type, unsigned long addr)
+                     int type, unsigned long addr, u32 flags)
 {
         struct fgraph_data *data = iter->private;
         struct trace_entry *ent = iter->ent;
@@ -803,27 +806,27 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
 
         if (type) {
                 /* Interrupt */
-                ret = print_graph_irq(iter, addr, type, cpu, ent->pid);
+                ret = print_graph_irq(iter, addr, type, cpu, ent->pid, flags);
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
 
         /* Absolute time */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) {
+        if (flags & TRACE_GRAPH_PRINT_ABS_TIME) {
                 ret = print_graph_abs_time(iter->ts, s);
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
 
         /* Cpu */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+        if (flags & TRACE_GRAPH_PRINT_CPU) {
                 ret = print_graph_cpu(s, cpu);
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
 
         /* Proc */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
+        if (flags & TRACE_GRAPH_PRINT_PROC) {
                 ret = print_graph_proc(s, ent->pid);
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
@@ -845,7 +848,7 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
 
 static enum print_line_t
 print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
-                        struct trace_iterator *iter)
+                        struct trace_iterator *iter, u32 flags)
 {
         struct fgraph_data *data = iter->private;
         struct ftrace_graph_ent *call = &field->graph_ent;
@@ -853,14 +856,14 @@ print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
         static enum print_line_t ret;
         int cpu = iter->cpu;
 
-        if (print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func))
+        if (print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func, flags))
                 return TRACE_TYPE_PARTIAL_LINE;
 
         leaf_ret = get_return_for_leaf(iter, field);
         if (leaf_ret)
-                ret = print_graph_entry_leaf(iter, field, leaf_ret, s);
+                ret = print_graph_entry_leaf(iter, field, leaf_ret, s, flags);
         else
-                ret = print_graph_entry_nested(iter, field, s, cpu);
+                ret = print_graph_entry_nested(iter, field, s, cpu, flags);
 
         if (data) {
                 /*
@@ -879,7 +882,8 @@ print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
 
 static enum print_line_t
 print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
-                   struct trace_entry *ent, struct trace_iterator *iter)
+                   struct trace_entry *ent, struct trace_iterator *iter,
+                   u32 flags)
 {
         unsigned long long duration = trace->rettime - trace->calltime;
         struct fgraph_data *data = iter->private;
@@ -909,16 +913,16 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
                 }
         }
 
-        if (print_graph_prologue(iter, s, 0, 0))
+        if (print_graph_prologue(iter, s, 0, 0, flags))
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* Overhead */
-        ret = print_graph_overhead(duration, s);
+        ret = print_graph_overhead(duration, s, flags);
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* Duration */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
+        if (flags & TRACE_GRAPH_PRINT_DURATION) {
                 ret = print_graph_duration(duration, s);
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
@@ -948,14 +952,15 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
         }
 
         /* Overrun */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) {
+        if (flags & TRACE_GRAPH_PRINT_OVERRUN) {
                 ret = trace_seq_printf(s, " (Overruns: %lu)\n",
                                         trace->overrun);
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
 
-        ret = print_graph_irq(iter, trace->func, TRACE_GRAPH_RET, cpu, pid);
+        ret = print_graph_irq(iter, trace->func, TRACE_GRAPH_RET,
+                              cpu, pid, flags);
         if (ret == TRACE_TYPE_PARTIAL_LINE)
                 return TRACE_TYPE_PARTIAL_LINE;
 
@@ -963,8 +968,8 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
 }
 
 static enum print_line_t
-print_graph_comment(struct trace_seq *s,  struct trace_entry *ent,
-                    struct trace_iterator *iter)
+print_graph_comment(struct trace_seq *s, struct trace_entry *ent,
+                    struct trace_iterator *iter, u32 flags)
 {
         unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
         struct fgraph_data *data = iter->private;
@@ -976,16 +981,16 @@ print_graph_comment(struct trace_seq *s,  struct trace_entry *ent,
         if (data)
                 depth = per_cpu_ptr(data->cpu_data, iter->cpu)->depth;
 
-        if (print_graph_prologue(iter, s, 0, 0))
+        if (print_graph_prologue(iter, s, 0, 0, flags))
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* No overhead */
-        ret = print_graph_overhead(-1, s);
+        ret = print_graph_overhead(-1, s, flags);
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* No time */
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
+        if (flags & TRACE_GRAPH_PRINT_DURATION) {
                 ret = trace_seq_printf(s, "            |  ");
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
@@ -1040,7 +1045,7 @@ print_graph_comment(struct trace_seq *s,  struct trace_entry *ent,
 
 
 enum print_line_t
-print_graph_function(struct trace_iterator *iter)
+print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 {
         struct ftrace_graph_ent_entry *field;
         struct fgraph_data *data = iter->private;
@@ -1061,7 +1066,7 @@ print_graph_function(struct trace_iterator *iter)
         if (data && data->failed) {
                 field = &data->ent;
                 iter->cpu = data->cpu;
-                ret = print_graph_entry(field, s, iter);
+                ret = print_graph_entry(field, s, iter, flags);
                 if (ret == TRACE_TYPE_HANDLED && iter->cpu != cpu) {
                         per_cpu_ptr(data->cpu_data, iter->cpu)->ignore = 1;
                         ret = TRACE_TYPE_NO_CONSUME;
@@ -1081,32 +1086,49 @@ print_graph_function(struct trace_iterator *iter)
                 struct ftrace_graph_ent_entry saved;
                 trace_assign_type(field, entry);
                 saved = *field;
-                return print_graph_entry(&saved, s, iter);
+                return print_graph_entry(&saved, s, iter, flags);
         }
         case TRACE_GRAPH_RET: {
                 struct ftrace_graph_ret_entry *field;
                 trace_assign_type(field, entry);
-                return print_graph_return(&field->ret, s, entry, iter);
+                return print_graph_return(&field->ret, s, entry, iter, flags);
         }
+        case TRACE_STACK:
+        case TRACE_FN:
+                /* dont trace stack and functions as comments */
+                return TRACE_TYPE_UNHANDLED;
+
         default:
-                return print_graph_comment(s, entry, iter);
+                return print_graph_comment(s, entry, iter, flags);
         }
 
         return TRACE_TYPE_HANDLED;
 }
 
-static void print_lat_header(struct seq_file *s)
+static enum print_line_t
+print_graph_function(struct trace_iterator *iter)
+{
+        return print_graph_function_flags(iter, tracer_flags.val);
+}
+
+static enum print_line_t
+print_graph_function_event(struct trace_iterator *iter, int flags)
+{
+        return print_graph_function(iter);
+}
+
+static void print_lat_header(struct seq_file *s, u32 flags)
 {
         static const char spaces[] = "                " /* 16 spaces */
                 "    "                                  /* 4 spaces */
                 "                 ";                    /* 17 spaces */
         int size = 0;
 
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
+        if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
                 size += 16;
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+        if (flags & TRACE_GRAPH_PRINT_CPU)
                 size += 4;
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+        if (flags & TRACE_GRAPH_PRINT_PROC)
                 size += 17;
 
         seq_printf(s, "#%.*s  _-----=> irqs-off        \n", size, spaces);
@@ -1117,43 +1139,48 @@ static void print_lat_header(struct seq_file *s)
         seq_printf(s, "#%.*s|||| /                     \n", size, spaces);
 }
 
-static void print_graph_headers(struct seq_file *s)
+void print_graph_headers_flags(struct seq_file *s, u32 flags)
 {
         int lat = trace_flags & TRACE_ITER_LATENCY_FMT;
 
         if (lat)
-                print_lat_header(s);
+                print_lat_header(s, flags);
 
         /* 1st line */
         seq_printf(s, "#");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
+        if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
                 seq_printf(s, "     TIME       ");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+        if (flags & TRACE_GRAPH_PRINT_CPU)
                 seq_printf(s, " CPU");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+        if (flags & TRACE_GRAPH_PRINT_PROC)
                 seq_printf(s, "  TASK/PID       ");
         if (lat)
                 seq_printf(s, "|||||");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
+        if (flags & TRACE_GRAPH_PRINT_DURATION)
                 seq_printf(s, "  DURATION   ");
         seq_printf(s, "               FUNCTION CALLS\n");
 
         /* 2nd line */
         seq_printf(s, "#");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
+        if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
                 seq_printf(s, "      |         ");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+        if (flags & TRACE_GRAPH_PRINT_CPU)
                 seq_printf(s, " |  ");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+        if (flags & TRACE_GRAPH_PRINT_PROC)
                 seq_printf(s, "   |    |        ");
         if (lat)
                 seq_printf(s, "|||||");
-        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
+        if (flags & TRACE_GRAPH_PRINT_DURATION)
                 seq_printf(s, "   |   |      ");
         seq_printf(s, "               |   |   |   |\n");
 }
 
-static void graph_trace_open(struct trace_iterator *iter)
+void print_graph_headers(struct seq_file *s)
+{
+        print_graph_headers_flags(s, tracer_flags.val);
+}
+
+void graph_trace_open(struct trace_iterator *iter)
 {
         /* pid and depth on the last trace processed */
         struct fgraph_data *data;
@@ -1188,7 +1215,7 @@ static void graph_trace_open(struct trace_iterator *iter)
         pr_warning("function graph tracer: not enough memory\n");
 }
 
-static void graph_trace_close(struct trace_iterator *iter)
+void graph_trace_close(struct trace_iterator *iter)
 {
         struct fgraph_data *data = iter->private;
 
@@ -1198,6 +1225,16 @@ static void graph_trace_close(struct trace_iterator *iter)
         }
 }
 
+static struct trace_event graph_trace_entry_event = {
+        .type           = TRACE_GRAPH_ENT,
+        .trace          = print_graph_function_event,
+};
+
+static struct trace_event graph_trace_ret_event = {
+        .type           = TRACE_GRAPH_RET,
+        .trace          = print_graph_function_event,
+};
+
 static struct tracer graph_trace __read_mostly = {
         .name           = "function_graph",
         .open           = graph_trace_open,
@@ -1219,6 +1256,16 @@ static __init int init_graph_trace(void)
 {
         max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
 
+        if (!register_ftrace_event(&graph_trace_entry_event)) {
+                pr_warning("Warning: could not register graph trace events\n");
+                return 1;
+        }
+
+        if (!register_ftrace_event(&graph_trace_ret_event)) {
+                pr_warning("Warning: could not register graph trace events\n");
+                return 1;
+        }
+
         return register_tracer(&graph_trace);
 }
 
diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
deleted file mode 100644
index 7b97000745f5..000000000000
--- a/kernel/trace/trace_hw_branches.c
+++ /dev/null
@@ -1,312 +0,0 @@
-/*
- * h/w branch tracer for x86 based on BTS
- *
- * Copyright (C) 2008-2009 Intel Corporation.
- * Markus Metzger <markus.t.metzger@gmail.com>, 2008-2009
- */
-#include <linux/kallsyms.h>
-#include <linux/debugfs.h>
-#include <linux/ftrace.h>
-#include <linux/module.h>
-#include <linux/cpu.h>
-#include <linux/smp.h>
-#include <linux/fs.h>
-
-#include <asm/ds.h>
-
-#include "trace_output.h"
-#include "trace.h"
-
-
-#define BTS_BUFFER_SIZE (1 << 13)
-
-static DEFINE_PER_CPU(struct bts_tracer *, hwb_tracer);
-static DEFINE_PER_CPU(unsigned char[BTS_BUFFER_SIZE], hwb_buffer);
-
-#define this_tracer per_cpu(hwb_tracer, smp_processor_id())
-
-static int trace_hw_branches_enabled __read_mostly;
-static int trace_hw_branches_suspended __read_mostly;
-static struct trace_array *hw_branch_trace __read_mostly;
-
-
-static void bts_trace_init_cpu(int cpu)
-{
-        per_cpu(hwb_tracer, cpu) =
-                ds_request_bts_cpu(cpu, per_cpu(hwb_buffer, cpu),
-                                   BTS_BUFFER_SIZE, NULL, (size_t)-1,
-                                   BTS_KERNEL);
-
-        if (IS_ERR(per_cpu(hwb_tracer, cpu)))
-                per_cpu(hwb_tracer, cpu) = NULL;
-}
-
-static int bts_trace_init(struct trace_array *tr)
-{
-        int cpu;
-
-        hw_branch_trace = tr;
-        trace_hw_branches_enabled = 0;
-
-        get_online_cpus();
-        for_each_online_cpu(cpu) {
-                bts_trace_init_cpu(cpu);
-
-                if (likely(per_cpu(hwb_tracer, cpu)))
-                        trace_hw_branches_enabled = 1;
-        }
-        trace_hw_branches_suspended = 0;
-        put_online_cpus();
-
-        /* If we could not enable tracing on a single cpu, we fail. */
-        return trace_hw_branches_enabled ? 0 : -EOPNOTSUPP;
-}
-
-static void bts_trace_reset(struct trace_array *tr)
-{
-        int cpu;
-
-        get_online_cpus();
-        for_each_online_cpu(cpu) {
-                if (likely(per_cpu(hwb_tracer, cpu))) {
-                        ds_release_bts(per_cpu(hwb_tracer, cpu));
-                        per_cpu(hwb_tracer, cpu) = NULL;
-                }
-        }
-        trace_hw_branches_enabled = 0;
-        trace_hw_branches_suspended = 0;
-        put_online_cpus();
-}
-
-static void bts_trace_start(struct trace_array *tr)
-{
-        int cpu;
-
-        get_online_cpus();
-        for_each_online_cpu(cpu)
-                if (likely(per_cpu(hwb_tracer, cpu)))
-                        ds_resume_bts(per_cpu(hwb_tracer, cpu));
-        trace_hw_branches_suspended = 0;
-        put_online_cpus();
-}
-
-static void bts_trace_stop(struct trace_array *tr)
-{
-        int cpu;
-
-        get_online_cpus();
-        for_each_online_cpu(cpu)
-                if (likely(per_cpu(hwb_tracer, cpu)))
-                        ds_suspend_bts(per_cpu(hwb_tracer, cpu));
-        trace_hw_branches_suspended = 1;
-        put_online_cpus();
-}
-
-static int __cpuinit bts_hotcpu_handler(struct notifier_block *nfb,
-                                     unsigned long action, void *hcpu)
-{
-        int cpu = (long)hcpu;
-
-        switch (action) {
-        case CPU_ONLINE:
-        case CPU_DOWN_FAILED:
-                /* The notification is sent with interrupts enabled. */
-                if (trace_hw_branches_enabled) {
-                        bts_trace_init_cpu(cpu);
-
-                        if (trace_hw_branches_suspended &&
-                            likely(per_cpu(hwb_tracer, cpu)))
-                                ds_suspend_bts(per_cpu(hwb_tracer, cpu));
-                }
-                break;
-
-        case CPU_DOWN_PREPARE:
-                /* The notification is sent with interrupts enabled. */
-                if (likely(per_cpu(hwb_tracer, cpu))) {
-                        ds_release_bts(per_cpu(hwb_tracer, cpu));
-                        per_cpu(hwb_tracer, cpu) = NULL;
-                }
-        }
-
-        return NOTIFY_DONE;
-}
-
-static struct notifier_block bts_hotcpu_notifier __cpuinitdata = {
-        .notifier_call = bts_hotcpu_handler
-};
-
-static void bts_trace_print_header(struct seq_file *m)
-{
-        seq_puts(m, "# CPU#        TO  <-  FROM\n");
-}
-
-static enum print_line_t bts_trace_print_line(struct trace_iterator *iter)
-{
-        unsigned long symflags = TRACE_ITER_SYM_OFFSET;
-        struct trace_entry *entry = iter->ent;
-        struct trace_seq *seq = &iter->seq;
-        struct hw_branch_entry *it;
-
-        trace_assign_type(it, entry);
-
-        if (entry->type == TRACE_HW_BRANCHES) {
-                if (trace_seq_printf(seq, "%4d  ", iter->cpu) &&
-                    seq_print_ip_sym(seq, it->to, symflags) &&
-                    trace_seq_printf(seq, "\t  <-  ") &&
-                    seq_print_ip_sym(seq, it->from, symflags) &&
-                    trace_seq_printf(seq, "\n"))
-                        return TRACE_TYPE_HANDLED;
-                return TRACE_TYPE_PARTIAL_LINE;
-        }
-        return TRACE_TYPE_UNHANDLED;
-}
-
-void trace_hw_branch(u64 from, u64 to)
-{
-        struct ftrace_event_call *call = &event_hw_branch;
-        struct trace_array *tr = hw_branch_trace;
-        struct ring_buffer_event *event;
-        struct ring_buffer *buf;
-        struct hw_branch_entry *entry;
-        unsigned long irq1;
-        int cpu;
-
-        if (unlikely(!tr))
-                return;
-
-        if (unlikely(!trace_hw_branches_enabled))
-                return;
-
-        local_irq_save(irq1);
-        cpu = raw_smp_processor_id();
-        if (atomic_inc_return(&tr->data[cpu]->disabled) != 1)
-                goto out;
-
-        buf = tr->buffer;
-        event = trace_buffer_lock_reserve(buf, TRACE_HW_BRANCHES,
-                                          sizeof(*entry), 0, 0);
-        if (!event)
-                goto out;
-        entry   = ring_buffer_event_data(event);
-        tracing_generic_entry_update(&entry->ent, 0, from);
-        entry->ent.type = TRACE_HW_BRANCHES;
-        entry->from = from;
-        entry->to   = to;
-        if (!filter_check_discard(call, entry, buf, event))
-                trace_buffer_unlock_commit(buf, event, 0, 0);
-
- out:
-        atomic_dec(&tr->data[cpu]->disabled);
-        local_irq_restore(irq1);
-}
-
-static void trace_bts_at(const struct bts_trace *trace, void *at)
-{
-        struct bts_struct bts;
-        int err = 0;
-
-        WARN_ON_ONCE(!trace->read);
-        if (!trace->read)
-                return;
-
-        err = trace->read(this_tracer, at, &bts);
-        if (err < 0)
-                return;
-
-        switch (bts.qualifier) {
-        case BTS_BRANCH:
-                trace_hw_branch(bts.variant.lbr.from, bts.variant.lbr.to);
-                break;
-        }
-}
-
-/*
- * Collect the trace on the current cpu and write it into the ftrace buffer.
- *
- * pre: tracing must be suspended on the current cpu
- */
-static void trace_bts_cpu(void *arg)
-{
-        struct trace_array *tr = (struct trace_array *)arg;
-        const struct bts_trace *trace;
-        unsigned char *at;
-
-        if (unlikely(!tr))
-                return;
-
-        if (unlikely(atomic_read(&tr->data[raw_smp_processor_id()]->disabled)))
-                return;
-
-        if (unlikely(!this_tracer))
-                return;
-
-        trace = ds_read_bts(this_tracer);
-        if (!trace)
-                return;
-
-        for (at = trace->ds.top; (void *)at < trace->ds.end;
-             at += trace->ds.size)
-                trace_bts_at(trace, at);
-
-        for (at = trace->ds.begin; (void *)at < trace->ds.top;
-             at += trace->ds.size)
-                trace_bts_at(trace, at);
-}
-
-static void trace_bts_prepare(struct trace_iterator *iter)
-{
-        int cpu;
-
-        get_online_cpus();
-        for_each_online_cpu(cpu)
-                if (likely(per_cpu(hwb_tracer, cpu)))
-                        ds_suspend_bts(per_cpu(hwb_tracer, cpu));
-        /*
-         * We need to collect the trace on the respective cpu since ftrace
-         * implicitly adds the record for the current cpu.
-         * Once that is more flexible, we could collect the data from any cpu.
-         */
-        on_each_cpu(trace_bts_cpu, iter->tr, 1);
-
-        for_each_online_cpu(cpu)
-                if (likely(per_cpu(hwb_tracer, cpu)))
-                        ds_resume_bts(per_cpu(hwb_tracer, cpu));
-        put_online_cpus();
-}
-
-static void trace_bts_close(struct trace_iterator *iter)
-{
-        tracing_reset_online_cpus(iter->tr);
-}
-
-void trace_hw_branch_oops(void)
-{
-        if (this_tracer) {
-                ds_suspend_bts_noirq(this_tracer);
-                trace_bts_cpu(hw_branch_trace);
-                ds_resume_bts_noirq(this_tracer);
-        }
-}
-
-struct tracer bts_tracer __read_mostly =
-{
-        .name           = "hw-branch-tracer",
-        .init           = bts_trace_init,
-        .reset          = bts_trace_reset,
-        .print_header   = bts_trace_print_header,
-        .print_line     = bts_trace_print_line,
-        .start          = bts_trace_start,
-        .stop           = bts_trace_stop,
-        .open           = trace_bts_prepare,
-        .close          = trace_bts_close,
-#ifdef CONFIG_FTRACE_SELFTEST
-        .selftest       = trace_selftest_startup_hw_branches,
-#endif /* CONFIG_FTRACE_SELFTEST */
-};
-
-__init static int init_bts_trace(void)
-{
-        register_hotcpu_notifier(&bts_hotcpu_notifier);
-        return register_tracer(&bts_tracer);
-}
-device_initcall(init_bts_trace);
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 2974bc7538c7..6fd486e0cef4 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -34,6 +34,9 @@ static int trace_type __read_mostly;
 
 static int save_lat_flag;
 
+static void stop_irqsoff_tracer(struct trace_array *tr, int graph);
+static int start_irqsoff_tracer(struct trace_array *tr, int graph);
+
 #ifdef CONFIG_PREEMPT_TRACER
 static inline int
 preempt_trace(void)
@@ -55,6 +58,23 @@ irq_trace(void)
 # define irq_trace() (0)
 #endif
 
+#define TRACE_DISPLAY_GRAPH     1
+
+static struct tracer_opt trace_opts[] = {
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+        /* display latency trace as call graph */
+        { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) },
+#endif
+        { } /* Empty entry */
+};
+
+static struct tracer_flags tracer_flags = {
+        .val  = 0,
+        .opts = trace_opts,
+};
+
+#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH)
+
 /*
  * Sequence count - we record it when starting a measurement and
  * skip the latency if the sequence has changed - some other section
@@ -108,6 +128,202 @@ static struct ftrace_ops trace_ops __read_mostly =
 };
 #endif /* CONFIG_FUNCTION_TRACER */
 
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static int irqsoff_set_flag(u32 old_flags, u32 bit, int set)
+{
+        int cpu;
+
+        if (!(bit & TRACE_DISPLAY_GRAPH))
+                return -EINVAL;
+
+        if (!(is_graph() ^ set))
+                return 0;
+
+        stop_irqsoff_tracer(irqsoff_trace, !set);
+
+        for_each_possible_cpu(cpu)
+                per_cpu(tracing_cpu, cpu) = 0;
+
+        tracing_max_latency = 0;
+        tracing_reset_online_cpus(irqsoff_trace);
+
+        return start_irqsoff_tracer(irqsoff_trace, set);
+}
+
+static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
+{
+        struct trace_array *tr = irqsoff_trace;
+        struct trace_array_cpu *data;
+        unsigned long flags;
+        long disabled;
+        int ret;
+        int cpu;
+        int pc;
+
+        cpu = raw_smp_processor_id();
+        if (likely(!per_cpu(tracing_cpu, cpu)))
+                return 0;
+
+        local_save_flags(flags);
+        /* slight chance to get a false positive on tracing_cpu */
+        if (!irqs_disabled_flags(flags))
+                return 0;
+
+        data = tr->data[cpu];
+        disabled = atomic_inc_return(&data->disabled);
+
+        if (likely(disabled == 1)) {
+                pc = preempt_count();
+                ret = __trace_graph_entry(tr, trace, flags, pc);
+        } else
+                ret = 0;
+
+        atomic_dec(&data->disabled);
+        return ret;
+}
+
+static void irqsoff_graph_return(struct ftrace_graph_ret *trace)
+{
+        struct trace_array *tr = irqsoff_trace;
+        struct trace_array_cpu *data;
+        unsigned long flags;
+        long disabled;
+        int cpu;
+        int pc;
+
+        cpu = raw_smp_processor_id();
+        if (likely(!per_cpu(tracing_cpu, cpu)))
+                return;
+
+        local_save_flags(flags);
+        /* slight chance to get a false positive on tracing_cpu */
+        if (!irqs_disabled_flags(flags))
+                return;
+
+        data = tr->data[cpu];
+        disabled = atomic_inc_return(&data->disabled);
+
+        if (likely(disabled == 1)) {
+                pc = preempt_count();
+                __trace_graph_return(tr, trace, flags, pc);
+        }
+
+        atomic_dec(&data->disabled);
+}
+
+static void irqsoff_trace_open(struct trace_iterator *iter)
+{
+        if (is_graph())
+                graph_trace_open(iter);
+
+}
+
+static void irqsoff_trace_close(struct trace_iterator *iter)
+{
+        if (iter->private)
+                graph_trace_close(iter);
+}
+
+#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \
+                            TRACE_GRAPH_PRINT_PROC)
+
+static enum print_line_t irqsoff_print_line(struct trace_iterator *iter)
+{
+        u32 flags = GRAPH_TRACER_FLAGS;
+
+        if (trace_flags & TRACE_ITER_LATENCY_FMT)
+                flags |= TRACE_GRAPH_PRINT_DURATION;
+        else
+                flags |= TRACE_GRAPH_PRINT_ABS_TIME;
+
+        /*
+         * In graph mode call the graph tracer output function,
+         * otherwise go with the TRACE_FN event handler
+         */
+        if (is_graph())
+                return print_graph_function_flags(iter, flags);
+
+        return TRACE_TYPE_UNHANDLED;
+}
+
+static void irqsoff_print_header(struct seq_file *s)
+{
+        if (is_graph()) {
+                struct trace_iterator *iter = s->private;
+                u32 flags = GRAPH_TRACER_FLAGS;
+
+                if (trace_flags & TRACE_ITER_LATENCY_FMT) {
+                        /* print nothing if the buffers are empty */
+                        if (trace_empty(iter))
+                                return;
+
+                        print_trace_header(s, iter);
+                        flags |= TRACE_GRAPH_PRINT_DURATION;
+                } else
+                        flags |= TRACE_GRAPH_PRINT_ABS_TIME;
+
+                print_graph_headers_flags(s, flags);
+        } else
+                trace_default_header(s);
+}
+
+static void
+trace_graph_function(struct trace_array *tr,
+                 unsigned long ip, unsigned long flags, int pc)
+{
+        u64 time = trace_clock_local();
+        struct ftrace_graph_ent ent = {
+                .func  = ip,
+                .depth = 0,
+        };
+        struct ftrace_graph_ret ret = {
+                .func     = ip,
+                .depth    = 0,
+                .calltime = time,
+                .rettime  = time,
+        };
+
+        __trace_graph_entry(tr, &ent, flags, pc);
+        __trace_graph_return(tr, &ret, flags, pc);
+}
+
+static void
+__trace_function(struct trace_array *tr,
+                 unsigned long ip, unsigned long parent_ip,
+                 unsigned long flags, int pc)
+{
+        if (!is_graph())
+                trace_function(tr, ip, parent_ip, flags, pc);
+        else {
+                trace_graph_function(tr, parent_ip, flags, pc);
+                trace_graph_function(tr, ip, flags, pc);
+        }
+}
+
+#else
+#define __trace_function trace_function
+
+static int irqsoff_set_flag(u32 old_flags, u32 bit, int set)
+{
+        return -EINVAL;
+}
+
+static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
+{
+        return -1;
+}
+
+static enum print_line_t irqsoff_print_line(struct trace_iterator *iter)
+{
+        return TRACE_TYPE_UNHANDLED;
+}
+
+static void irqsoff_graph_return(struct ftrace_graph_ret *trace) { }
+static void irqsoff_print_header(struct seq_file *s) { }
+static void irqsoff_trace_open(struct trace_iterator *iter) { }
+static void irqsoff_trace_close(struct trace_iterator *iter) { }
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
 /*
  * Should this new latency be reported/recorded?
  */
@@ -150,7 +366,7 @@ check_critical_timing(struct trace_array *tr,
         if (!report_latency(delta))
                 goto out_unlock;
 
-        trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
+        __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
         /* Skip 5 functions to get to the irq/preempt enable function */
         __trace_stack(tr, flags, 5, pc);
 
@@ -172,7 +388,7 @@ out_unlock:
 out:
         data->critical_sequence = max_sequence;
         data->preempt_timestamp = ftrace_now(cpu);
-        trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
+        __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
 }
 
 static inline void
@@ -204,7 +420,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip)
 
         local_save_flags(flags);
 
-        trace_function(tr, ip, parent_ip, flags, preempt_count());
+        __trace_function(tr, ip, parent_ip, flags, preempt_count());
 
         per_cpu(tracing_cpu, cpu) = 1;
 
@@ -238,7 +454,7 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip)
         atomic_inc(&data->disabled);
 
         local_save_flags(flags);
-        trace_function(tr, ip, parent_ip, flags, preempt_count());
+        __trace_function(tr, ip, parent_ip, flags, preempt_count());
         check_critical_timing(tr, data, parent_ip ? : ip, cpu);
         data->critical_start = 0;
         atomic_dec(&data->disabled);
@@ -347,19 +563,32 @@ void trace_preempt_off(unsigned long a0, unsigned long a1)
 }
 #endif /* CONFIG_PREEMPT_TRACER */
 
-static void start_irqsoff_tracer(struct trace_array *tr)
+static int start_irqsoff_tracer(struct trace_array *tr, int graph)
 {
-        register_ftrace_function(&trace_ops);
-        if (tracing_is_enabled())
+        int ret = 0;
+
+        if (!graph)
+                ret = register_ftrace_function(&trace_ops);
+        else
+                ret = register_ftrace_graph(&irqsoff_graph_return,
+                                            &irqsoff_graph_entry);
+
+        if (!ret && tracing_is_enabled())
                 tracer_enabled = 1;
         else
                 tracer_enabled = 0;
+
+        return ret;
 }
 
-static void stop_irqsoff_tracer(struct trace_array *tr)
+static void stop_irqsoff_tracer(struct trace_array *tr, int graph)
 {
         tracer_enabled = 0;
-        unregister_ftrace_function(&trace_ops);
+
+        if (!graph)
+                unregister_ftrace_function(&trace_ops);
+        else
+                unregister_ftrace_graph();
 }
 
 static void __irqsoff_tracer_init(struct trace_array *tr)
@@ -372,12 +601,14 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
         /* make sure that the tracer is visible */
         smp_wmb();
         tracing_reset_online_cpus(tr);
-        start_irqsoff_tracer(tr);
+
+        if (start_irqsoff_tracer(tr, is_graph()))
+                printk(KERN_ERR "failed to start irqsoff tracer\n");
 }
 
 static void irqsoff_tracer_reset(struct trace_array *tr)
 {
-        stop_irqsoff_tracer(tr);
+        stop_irqsoff_tracer(tr, is_graph());
 
         if (!save_lat_flag)
                 trace_flags &= ~TRACE_ITER_LATENCY_FMT;
@@ -409,9 +640,15 @@ static struct tracer irqsoff_tracer __read_mostly =
         .start          = irqsoff_tracer_start,
         .stop           = irqsoff_tracer_stop,
         .print_max      = 1,
+        .print_header   = irqsoff_print_header,
+        .print_line     = irqsoff_print_line,
+        .flags          = &tracer_flags,
+        .set_flag       = irqsoff_set_flag,
 #ifdef CONFIG_FTRACE_SELFTEST
         .selftest    = trace_selftest_startup_irqsoff,
 #endif
+        .open           = irqsoff_trace_open,
+        .close          = irqsoff_trace_close,
 };
 # define register_irqsoff(trace) register_tracer(&trace)
 #else
@@ -435,9 +672,15 @@ static struct tracer preemptoff_tracer __read_mostly =
         .start          = irqsoff_tracer_start,
         .stop           = irqsoff_tracer_stop,
         .print_max      = 1,
+        .print_header   = irqsoff_print_header,
+        .print_line     = irqsoff_print_line,
+        .flags          = &tracer_flags,
+        .set_flag       = irqsoff_set_flag,
 #ifdef CONFIG_FTRACE_SELFTEST
         .selftest    = trace_selftest_startup_preemptoff,
 #endif
+        .open           = irqsoff_trace_open,
+        .close          = irqsoff_trace_close,
 };
 # define register_preemptoff(trace) register_tracer(&trace)
 #else
@@ -463,9 +706,15 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
         .start          = irqsoff_tracer_start,
         .stop           = irqsoff_tracer_stop,
         .print_max      = 1,
+        .print_header   = irqsoff_print_header,
+        .print_line     = irqsoff_print_line,
+        .flags          = &tracer_flags,
+        .set_flag       = irqsoff_set_flag,
 #ifdef CONFIG_FTRACE_SELFTEST
         .selftest    = trace_selftest_startup_preemptirqsoff,
 #endif
+        .open           = irqsoff_trace_open,
+        .close          = irqsoff_trace_close,
 };
 
 # define register_preemptirqsoff(trace) register_tracer(&trace)
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 1251e367bae9..a7514326052b 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -29,6 +29,8 @@
 #include <linux/ctype.h>
 #include <linux/ptrace.h>
 #include <linux/perf_event.h>
+#include <linux/stringify.h>
+#include <asm/bitsperlong.h>
 
 #include "trace.h"
 #include "trace_output.h"
@@ -40,7 +42,6 @@
 
 /* Reserved field names */
 #define FIELD_STRING_IP "__probe_ip"
-#define FIELD_STRING_NARGS "__probe_nargs"
 #define FIELD_STRING_RETIP "__probe_ret_ip"
 #define FIELD_STRING_FUNC "__probe_func"
 
@@ -52,56 +53,102 @@ const char *reserved_field_names[] = {
         "common_tgid",
         "common_lock_depth",
         FIELD_STRING_IP,
-        FIELD_STRING_NARGS,
         FIELD_STRING_RETIP,
         FIELD_STRING_FUNC,
 };
 
-struct fetch_func {
-        unsigned long (*func)(struct pt_regs *, void *);
+/* Printing function type */
+typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *);
+#define PRINT_TYPE_FUNC_NAME(type)      print_type_##type
+#define PRINT_TYPE_FMT_NAME(type)       print_type_format_##type
+
+/* Printing  in basic type function template */
+#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast)                   \
+static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s,    \
+                                                const char *name, void *data)\
+{                                                                       \
+        return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\
+}                                                                       \
+static const char PRINT_TYPE_FMT_NAME(type)[] = fmt;
+
+DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long)
+DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long)
+
+/* Data fetch function type */
+typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
+
+struct fetch_param {
+        fetch_func_t    fn;
         void *data;
 };
 
-static __kprobes unsigned long call_fetch(struct fetch_func *f,
-                                          struct pt_regs *regs)
+static __kprobes void call_fetch(struct fetch_param *fprm,
+                                 struct pt_regs *regs, void *dest)
 {
-        return f->func(regs, f->data);
+        return fprm->fn(regs, fprm->data, dest);
 }
 
-/* fetch handlers */
-static __kprobes unsigned long fetch_register(struct pt_regs *regs,
-                                              void *offset)
-{
-        return regs_get_register(regs, (unsigned int)((unsigned long)offset));
+#define FETCH_FUNC_NAME(kind, type)     fetch_##kind##_##type
+/*
+ * Define macro for basic types - we don't need to define s* types, because
+ * we have to care only about bitwidth at recording time.
+ */
+#define DEFINE_BASIC_FETCH_FUNCS(kind)  \
+DEFINE_FETCH_##kind(u8)                 \
+DEFINE_FETCH_##kind(u16)                \
+DEFINE_FETCH_##kind(u32)                \
+DEFINE_FETCH_##kind(u64)
+
+#define CHECK_BASIC_FETCH_FUNCS(kind, fn)       \
+        ((FETCH_FUNC_NAME(kind, u8) == fn) ||   \
+         (FETCH_FUNC_NAME(kind, u16) == fn) ||  \
+         (FETCH_FUNC_NAME(kind, u32) == fn) ||  \
+         (FETCH_FUNC_NAME(kind, u64) == fn))
+
+/* Data fetch function templates */
+#define DEFINE_FETCH_reg(type)                                          \
+static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs,  \
+                                          void *offset, void *dest)     \
+{                                                                       \
+        *(type *)dest = (type)regs_get_register(regs,                   \
+                                (unsigned int)((unsigned long)offset)); \
 }
-
-static __kprobes unsigned long fetch_stack(struct pt_regs *regs,
-                                           void *num)
-{
-        return regs_get_kernel_stack_nth(regs,
-                                         (unsigned int)((unsigned long)num));
+DEFINE_BASIC_FETCH_FUNCS(reg)
+
+#define DEFINE_FETCH_stack(type)                                        \
+static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
+                                          void *offset, void *dest)     \
+{                                                                       \
+        *(type *)dest = (type)regs_get_kernel_stack_nth(regs,           \
+                                (unsigned int)((unsigned long)offset)); \
 }
+DEFINE_BASIC_FETCH_FUNCS(stack)
 
-static __kprobes unsigned long fetch_memory(struct pt_regs *regs, void *addr)
-{
-        unsigned long retval;
-
-        if (probe_kernel_address(addr, retval))
-                return 0;
-        return retval;
+#define DEFINE_FETCH_retval(type)                                       \
+static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\
+                                          void *dummy, void *dest)      \
+{                                                                       \
+        *(type *)dest = (type)regs_return_value(regs);                  \
 }
-
-static __kprobes unsigned long fetch_retvalue(struct pt_regs *regs,
-                                              void *dummy)
-{
-        return regs_return_value(regs);
-}
-
-static __kprobes unsigned long fetch_stack_address(struct pt_regs *regs,
-                                                   void *dummy)
-{
-        return kernel_stack_pointer(regs);
+DEFINE_BASIC_FETCH_FUNCS(retval)
+
+#define DEFINE_FETCH_memory(type)                                       \
+static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
+                                          void *addr, void *dest)       \
+{                                                                       \
+        type retval;                                                    \
+        if (probe_kernel_address(addr, retval))                         \
+                *(type *)dest = 0;                                      \
+        else                                                            \
+                *(type *)dest = retval;                                 \
 }
+DEFINE_BASIC_FETCH_FUNCS(memory)
 
 /* Memory fetching by symbol */
 struct symbol_cache {
@@ -145,51 +192,126 @@ static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
         return sc;
 }
 
-static __kprobes unsigned long fetch_symbol(struct pt_regs *regs, void *data)
-{
-        struct symbol_cache *sc = data;
-
-        if (sc->addr)
-                return fetch_memory(regs, (void *)sc->addr);
-        else
-                return 0;
+#define DEFINE_FETCH_symbol(type)                                       \
+static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\
+                                          void *data, void *dest)       \
+{                                                                       \
+        struct symbol_cache *sc = data;                                 \
+        if (sc->addr)                                                   \
+                fetch_memory_##type(regs, (void *)sc->addr, dest);      \
+        else                                                            \
+                *(type *)dest = 0;                                      \
 }
+DEFINE_BASIC_FETCH_FUNCS(symbol)
 
-/* Special indirect memory access interface */
-struct indirect_fetch_data {
-        struct fetch_func orig;
+/* Dereference memory access function */
+struct deref_fetch_param {
+        struct fetch_param orig;
         long offset;
 };
 
-static __kprobes unsigned long fetch_indirect(struct pt_regs *regs, void *data)
-{
-        struct indirect_fetch_data *ind = data;
-        unsigned long addr;
-
-        addr = call_fetch(&ind->orig, regs);
-        if (addr) {
-                addr += ind->offset;
-                return fetch_memory(regs, (void *)addr);
-        } else
-                return 0;
+#define DEFINE_FETCH_deref(type)                                        \
+static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\
+                                            void *data, void *dest)     \
+{                                                                       \
+        struct deref_fetch_param *dprm = data;                          \
+        unsigned long addr;                                             \
+        call_fetch(&dprm->orig, regs, &addr);                           \
+        if (addr) {                                                     \
+                addr += dprm->offset;                                   \
+                fetch_memory_##type(regs, (void *)addr, dest);          \
+        } else                                                          \
+                *(type *)dest = 0;                                      \
 }
+DEFINE_BASIC_FETCH_FUNCS(deref)
 
-static __kprobes void free_indirect_fetch_data(struct indirect_fetch_data *data)
+static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
 {
-        if (data->orig.func == fetch_indirect)
-                free_indirect_fetch_data(data->orig.data);
-        else if (data->orig.func == fetch_symbol)
+        if (CHECK_BASIC_FETCH_FUNCS(deref, data->orig.fn))
+                free_deref_fetch_param(data->orig.data);
+        else if (CHECK_BASIC_FETCH_FUNCS(symbol, data->orig.fn))
                 free_symbol_cache(data->orig.data);
         kfree(data);
 }
 
+/* Default (unsigned long) fetch type */
+#define __DEFAULT_FETCH_TYPE(t) u##t
+#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
+#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
+#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
+
+#define ASSIGN_FETCH_FUNC(kind, type)   \
+        .kind = FETCH_FUNC_NAME(kind, type)
+
+#define ASSIGN_FETCH_TYPE(ptype, ftype, sign)   \
+        {.name = #ptype,                        \
+         .size = sizeof(ftype),                 \
+         .is_signed = sign,                     \
+         .print = PRINT_TYPE_FUNC_NAME(ptype),  \
+         .fmt = PRINT_TYPE_FMT_NAME(ptype),     \
+ASSIGN_FETCH_FUNC(reg, ftype),                  \
+ASSIGN_FETCH_FUNC(stack, ftype),                \
+ASSIGN_FETCH_FUNC(retval, ftype),               \
+ASSIGN_FETCH_FUNC(memory, ftype),               \
+ASSIGN_FETCH_FUNC(symbol, ftype),               \
+ASSIGN_FETCH_FUNC(deref, ftype),                \
+        }
+
+/* Fetch type information table */
+static const struct fetch_type {
+        const char      *name;          /* Name of type */
+        size_t          size;           /* Byte size of type */
+        int             is_signed;      /* Signed flag */
+        print_type_func_t       print;  /* Print functions */
+        const char      *fmt;           /* Fromat string */
+        /* Fetch functions */
+        fetch_func_t    reg;
+        fetch_func_t    stack;
+        fetch_func_t    retval;
+        fetch_func_t    memory;
+        fetch_func_t    symbol;
+        fetch_func_t    deref;
+} fetch_type_table[] = {
+        ASSIGN_FETCH_TYPE(u8,  u8,  0),
+        ASSIGN_FETCH_TYPE(u16, u16, 0),
+        ASSIGN_FETCH_TYPE(u32, u32, 0),
+        ASSIGN_FETCH_TYPE(u64, u64, 0),
+        ASSIGN_FETCH_TYPE(s8,  u8,  1),
+        ASSIGN_FETCH_TYPE(s16, u16, 1),
+        ASSIGN_FETCH_TYPE(s32, u32, 1),
+        ASSIGN_FETCH_TYPE(s64, u64, 1),
+};
+
+static const struct fetch_type *find_fetch_type(const char *type)
+{
+        int i;
+
+        if (!type)
+                type = DEFAULT_FETCH_TYPE_STR;
+
+        for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++)
+                if (strcmp(type, fetch_type_table[i].name) == 0)
+                        return &fetch_type_table[i];
+        return NULL;
+}
+
+/* Special function : only accept unsigned long */
+static __kprobes void fetch_stack_address(struct pt_regs *regs,
+                                          void *dummy, void *dest)
+{
+        *(unsigned long *)dest = kernel_stack_pointer(regs);
+}
+
 /**
  * Kprobe event core functions
  */
 
 struct probe_arg {
-        struct fetch_func       fetch;
-        const char              *name;
+        struct fetch_param      fetch;
+        unsigned int            offset; /* Offset from argument entry */
+        const char              *name;  /* Name of this argument */
+        const char              *comm;  /* Command of this argument */
+        const struct fetch_type *type;  /* Type of this argument */
 };
 
 /* Flags for trace_probe */
@@ -204,6 +326,7 @@ struct trace_probe {
         const char              *symbol;        /* symbol name */
         struct ftrace_event_call        call;
         struct trace_event              event;
+        ssize_t                 size;           /* trace entry size */
         unsigned int            nr_args;
         struct probe_arg        args[];
 };
@@ -212,6 +335,7 @@ struct trace_probe {
         (offsetof(struct trace_probe, args) +   \
         (sizeof(struct probe_arg) * (n)))
 
+
 static __kprobes int probe_is_return(struct trace_probe *tp)
 {
         return tp->rp.handler != NULL;
@@ -222,49 +346,6 @@ static __kprobes const char *probe_symbol(struct trace_probe *tp)
         return tp->symbol ? tp->symbol : "unknown";
 }
 
-static int probe_arg_string(char *buf, size_t n, struct fetch_func *ff)
-{
-        int ret = -EINVAL;
-
-        if (ff->func == fetch_register) {
-                const char *name;
-                name = regs_query_register_name((unsigned int)((long)ff->data));
-                ret = snprintf(buf, n, "%%%s", name);
-        } else if (ff->func == fetch_stack)
-                ret = snprintf(buf, n, "$stack%lu", (unsigned long)ff->data);
-        else if (ff->func == fetch_memory)
-                ret = snprintf(buf, n, "@0x%p", ff->data);
-        else if (ff->func == fetch_symbol) {
-                struct symbol_cache *sc = ff->data;
-                if (sc->offset)
-                        ret = snprintf(buf, n, "@%s%+ld", sc->symbol,
-                                        sc->offset);
-                else
-                        ret = snprintf(buf, n, "@%s", sc->symbol);
-        } else if (ff->func == fetch_retvalue)
-                ret = snprintf(buf, n, "$retval");
-        else if (ff->func == fetch_stack_address)
-                ret = snprintf(buf, n, "$stack");
-        else if (ff->func == fetch_indirect) {
-                struct indirect_fetch_data *id = ff->data;
-                size_t l = 0;
-                ret = snprintf(buf, n, "%+ld(", id->offset);
-                if (ret >= n)
-                        goto end;
-                l += ret;
-                ret = probe_arg_string(buf + l, n - l, &id->orig);
-                if (ret < 0)
-                        goto end;
-                l += ret;
-                ret = snprintf(buf + l, n - l, ")");
-                ret += l;
-        }
-end:
-        if (ret >= n)
-                return -ENOSPC;
-        return ret;
-}
-
 static int register_probe_event(struct trace_probe *tp);
 static void unregister_probe_event(struct trace_probe *tp);
 
@@ -347,11 +428,12 @@ error:
 
 static void free_probe_arg(struct probe_arg *arg)
 {
-        if (arg->fetch.func == fetch_symbol)
+        if (CHECK_BASIC_FETCH_FUNCS(deref, arg->fetch.fn))
+                free_deref_fetch_param(arg->fetch.data);
+        else if (CHECK_BASIC_FETCH_FUNCS(symbol, arg->fetch.fn))
                 free_symbol_cache(arg->fetch.data);
-        else if (arg->fetch.func == fetch_indirect)
-                free_indirect_fetch_data(arg->fetch.data);
         kfree(arg->name);
+        kfree(arg->comm);
 }
 
 static void free_trace_probe(struct trace_probe *tp)
@@ -457,28 +539,30 @@ static int split_symbol_offset(char *symbol, unsigned long *offset)
 #define PARAM_MAX_ARGS 16
 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 
-static int parse_probe_vars(char *arg, struct fetch_func *ff, int is_return)
+static int parse_probe_vars(char *arg, const struct fetch_type *t,
+                            struct fetch_param *f, int is_return)
 {
         int ret = 0;
         unsigned long param;
 
         if (strcmp(arg, "retval") == 0) {
-                if (is_return) {
-                        ff->func = fetch_retvalue;
-                        ff->data = NULL;
-                } else
+                if (is_return)
+                        f->fn = t->retval;
+                else
                         ret = -EINVAL;
         } else if (strncmp(arg, "stack", 5) == 0) {
                 if (arg[5] == '\0') {
-                        ff->func = fetch_stack_address;
-                        ff->data = NULL;
+                        if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
+                                f->fn = fetch_stack_address;
+                        else
+                                ret = -EINVAL;
                 } else if (isdigit(arg[5])) {
                         ret = strict_strtoul(arg + 5, 10, &param);
                         if (ret || param > PARAM_MAX_STACK)
                                 ret = -EINVAL;
                         else {
-                                ff->func = fetch_stack;
-                                ff->data = (void *)param;
+                                f->fn = t->stack;
+                                f->data = (void *)param;
                         }
                 } else
                         ret = -EINVAL;
@@ -488,7 +572,8 @@ static int parse_probe_vars(char *arg, struct fetch_func *ff, int is_return)
 }
 
 /* Recursive argument parser */
-static int __parse_probe_arg(char *arg, struct fetch_func *ff, int is_return)
+static int __parse_probe_arg(char *arg, const struct fetch_type *t,
+                             struct fetch_param *f, int is_return)
 {
         int ret = 0;
         unsigned long param;
@@ -497,13 +582,13 @@ static int __parse_probe_arg(char *arg, struct fetch_func *ff, int is_return)
 
         switch (arg[0]) {
         case '$':
-                ret = parse_probe_vars(arg + 1, ff, is_return);
+                ret = parse_probe_vars(arg + 1, t, f, is_return);
                 break;
         case '%':       /* named register */
                 ret = regs_query_register_offset(arg + 1);
                 if (ret >= 0) {
-                        ff->func = fetch_register;
-                        ff->data = (void *)(unsigned long)ret;
+                        f->fn = t->reg;
+                        f->data = (void *)(unsigned long)ret;
                         ret = 0;
                 }
                 break;
@@ -512,26 +597,22 @@ static int __parse_probe_arg(char *arg, struct fetch_func *ff, int is_return)
                         ret = strict_strtoul(arg + 1, 0, &param);
                         if (ret)
                                 break;
-                        ff->func = fetch_memory;
-                        ff->data = (void *)param;
+                        f->fn = t->memory;
+                        f->data = (void *)param;
                 } else {
                         ret = split_symbol_offset(arg + 1, &offset);
                         if (ret)
                                 break;
-                        ff->data = alloc_symbol_cache(arg + 1, offset);
-                        if (ff->data)
-                                ff->func = fetch_symbol;
-                        else
-                                ret = -EINVAL;
+                        f->data = alloc_symbol_cache(arg + 1, offset);
+                        if (f->data)
+                                f->fn = t->symbol;
                 }
                 break;
-        case '+':       /* indirect memory */
+        case '+':       /* deref memory */
         case '-':
                 tmp = strchr(arg, '(');
-                if (!tmp) {
-                        ret = -EINVAL;
+                if (!tmp)
                         break;
-                }
                 *tmp = '\0';
                 ret = strict_strtol(arg + 1, 0, &offset);
                 if (ret)
@@ -541,38 +622,58 @@ static int __parse_probe_arg(char *arg, struct fetch_func *ff, int is_return)
                 arg = tmp + 1;
                 tmp = strrchr(arg, ')');
                 if (tmp) {
-                        struct indirect_fetch_data *id;
+                        struct deref_fetch_param *dprm;
+                        const struct fetch_type *t2 = find_fetch_type(NULL);
                         *tmp = '\0';
-                        id = kzalloc(sizeof(struct indirect_fetch_data),
-                                     GFP_KERNEL);
-                        if (!id)
+                        dprm = kzalloc(sizeof(struct deref_fetch_param),
+                                       GFP_KERNEL);
+                        if (!dprm)
                                 return -ENOMEM;
-                        id->offset = offset;
-                        ret = __parse_probe_arg(arg, &id->orig, is_return);
+                        dprm->offset = offset;
+                        ret = __parse_probe_arg(arg, t2, &dprm->orig,
+                                                is_return);
                         if (ret)
-                                kfree(id);
+                                kfree(dprm);
                         else {
-                                ff->func = fetch_indirect;
-                                ff->data = (void *)id;
+                                f->fn = t->deref;
+                                f->data = (void *)dprm;
                         }
-                } else
-                        ret = -EINVAL;
+                }
                 break;
-        default:
-                /* TODO: support custom handler */
-                ret = -EINVAL;
         }
+        if (!ret && !f->fn)
+                ret = -EINVAL;
         return ret;
 }
 
 /* String length checking wrapper */
-static int parse_probe_arg(char *arg, struct fetch_func *ff, int is_return)
+static int parse_probe_arg(char *arg, struct trace_probe *tp,
+                           struct probe_arg *parg, int is_return)
 {
+        const char *t;
+
         if (strlen(arg) > MAX_ARGSTR_LEN) {
                 pr_info("Argument is too long.: %s\n",  arg);
                 return -ENOSPC;
         }
-        return __parse_probe_arg(arg, ff, is_return);
+        parg->comm = kstrdup(arg, GFP_KERNEL);
+        if (!parg->comm) {
+                pr_info("Failed to allocate memory for command '%s'.\n", arg);
+                return -ENOMEM;
+        }
+        t = strchr(parg->comm, ':');
+        if (t) {
+                arg[t - parg->comm] = '\0';
+                t++;
+        }
+        parg->type = find_fetch_type(t);
+        if (!parg->type) {
+                pr_info("Unsupported type: %s\n", t);
+                return -EINVAL;
+        }
+        parg->offset = tp->size;
+        tp->size += parg->type->size;
+        return __parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
 }
 
 /* Return 1 if name is reserved or already used by another argument */
@@ -602,15 +703,18 @@ static int create_trace_probe(int argc, char **argv)
          *  @ADDR       : fetch memory at ADDR (ADDR should be in kernel)
          *  @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
          *  %REG        : fetch register REG
-         * Indirect memory fetch:
+         * Dereferencing memory fetch:
          *  +|-offs(ARG) : fetch memory at ARG +|- offs address.
          * Alias name of args:
          *  NAME=FETCHARG : set NAME as alias of FETCHARG.
+         * Type of args:
+         *  FETCHARG:TYPE : use TYPE instead of unsigned long.
          */
         struct trace_probe *tp;
         int i, ret = 0;
         int is_return = 0, is_delete = 0;
-        char *symbol = NULL, *event = NULL, *arg = NULL, *group = NULL;
+        char *symbol = NULL, *event = NULL, *group = NULL;
+        char *arg, *tmp;
         unsigned long offset = 0;
         void *addr = NULL;
         char buf[MAX_EVENT_NAME_LEN];
@@ -723,13 +827,6 @@ static int create_trace_probe(int argc, char **argv)
                 else
                         arg = argv[i];
 
-                if (conflict_field_name(argv[i], tp->args, i)) {
-                        pr_info("Argument%d name '%s' conflicts with "
-                                "another field.\n", i, argv[i]);
-                        ret = -EINVAL;
-                        goto error;
-                }
-
                 tp->args[i].name = kstrdup(argv[i], GFP_KERNEL);
                 if (!tp->args[i].name) {
                         pr_info("Failed to allocate argument%d name '%s'.\n",
@@ -737,9 +834,19 @@ static int create_trace_probe(int argc, char **argv)
                         ret = -ENOMEM;
                         goto error;
                 }
+                tmp = strchr(tp->args[i].name, ':');
+                if (tmp)
+                        *tmp = '_';     /* convert : to _ */
+
+                if (conflict_field_name(tp->args[i].name, tp->args, i)) {
+                        pr_info("Argument%d name '%s' conflicts with "
+                                "another field.\n", i, argv[i]);
+                        ret = -EINVAL;
+                        goto error;
+                }
 
                 /* Parse fetch argument */
-                ret = parse_probe_arg(arg, &tp->args[i].fetch, is_return);
+                ret = parse_probe_arg(arg, tp, &tp->args[i], is_return);
                 if (ret) {
                         pr_info("Parse error at argument%d. (%d)\n", i, ret);
                         kfree(tp->args[i].name);
@@ -794,8 +901,7 @@ static void probes_seq_stop(struct seq_file *m, void *v)
 static int probes_seq_show(struct seq_file *m, void *v)
 {
         struct trace_probe *tp = v;
-        int i, ret;
-        char buf[MAX_ARGSTR_LEN + 1];
+        int i;
 
         seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p');
         seq_printf(m, ":%s/%s", tp->call.system, tp->call.name);
@@ -807,15 +913,10 @@ static int probes_seq_show(struct seq_file *m, void *v)
         else
                 seq_printf(m, " %s", probe_symbol(tp));
 
-        for (i = 0; i < tp->nr_args; i++) {
-                ret = probe_arg_string(buf, MAX_ARGSTR_LEN, &tp->args[i].fetch);
-                if (ret < 0) {
-                        pr_warning("Argument%d decoding error(%d).\n", i, ret);
-                        return ret;
-                }
-                seq_printf(m, " %s=%s", tp->args[i].name, buf);
-        }
+        for (i = 0; i < tp->nr_args; i++)
+                seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm);
         seq_printf(m, "\n");
+
         return 0;
 }
 
@@ -945,9 +1046,10 @@ static const struct file_operations kprobe_profile_ops = {
 static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
 {
         struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
-        struct kprobe_trace_entry *entry;
+        struct kprobe_trace_entry_head *entry;
         struct ring_buffer_event *event;
         struct ring_buffer *buffer;
+        u8 *data;
         int size, i, pc;
         unsigned long irq_flags;
         struct ftrace_event_call *call = &tp->call;
@@ -957,7 +1059,7 @@ static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
         local_save_flags(irq_flags);
         pc = preempt_count();
 
-        size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args);
+        size = sizeof(*entry) + tp->size;
 
         event = trace_current_buffer_lock_reserve(&buffer, call->id, size,
                                                   irq_flags, pc);
@@ -965,10 +1067,10 @@ static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
                 return;
 
         entry = ring_buffer_event_data(event);
-        entry->nargs = tp->nr_args;
         entry->ip = (unsigned long)kp->addr;
+        data = (u8 *)&entry[1];
         for (i = 0; i < tp->nr_args; i++)
-                entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
+                call_fetch(&tp->args[i].fetch, regs, data + tp->args[i].offset);
 
         if (!filter_current_check_discard(buffer, call, entry, event))
                 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
@@ -979,9 +1081,10 @@ static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
                                           struct pt_regs *regs)
 {
         struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
-        struct kretprobe_trace_entry *entry;
+        struct kretprobe_trace_entry_head *entry;
         struct ring_buffer_event *event;
         struct ring_buffer *buffer;
+        u8 *data;
         int size, i, pc;
         unsigned long irq_flags;
         struct ftrace_event_call *call = &tp->call;
@@ -989,7 +1092,7 @@ static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
         local_save_flags(irq_flags);
         pc = preempt_count();
 
-        size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args);
+        size = sizeof(*entry) + tp->size;
 
         event = trace_current_buffer_lock_reserve(&buffer, call->id, size,
                                                   irq_flags, pc);
@@ -997,11 +1100,11 @@ static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
                 return;
 
         entry = ring_buffer_event_data(event);
-        entry->nargs = tp->nr_args;
         entry->func = (unsigned long)tp->rp.kp.addr;
         entry->ret_ip = (unsigned long)ri->ret_addr;
+        data = (u8 *)&entry[1];
         for (i = 0; i < tp->nr_args; i++)
-                entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
+                call_fetch(&tp->args[i].fetch, regs, data + tp->args[i].offset);
 
         if (!filter_current_check_discard(buffer, call, entry, event))
                 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
@@ -1011,13 +1114,14 @@ static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
 enum print_line_t
 print_kprobe_event(struct trace_iterator *iter, int flags)
 {
-        struct kprobe_trace_entry *field;
+        struct kprobe_trace_entry_head *field;
         struct trace_seq *s = &iter->seq;
         struct trace_event *event;
         struct trace_probe *tp;
+        u8 *data;
         int i;
 
-        field = (struct kprobe_trace_entry *)iter->ent;
+        field = (struct kprobe_trace_entry_head *)iter->ent;
         event = ftrace_find_event(field->ent.type);
         tp = container_of(event, struct trace_probe, event);
 
@@ -1030,9 +1134,10 @@ print_kprobe_event(struct trace_iterator *iter, int flags)
         if (!trace_seq_puts(s, ")"))
                 goto partial;
 
-        for (i = 0; i < field->nargs; i++)
-                if (!trace_seq_printf(s, " %s=%lx",
-                                      tp->args[i].name, field->args[i]))
+        data = (u8 *)&field[1];
+        for (i = 0; i < tp->nr_args; i++)
+                if (!tp->args[i].type->print(s, tp->args[i].name,
+                                             data + tp->args[i].offset))
                         goto partial;
 
         if (!trace_seq_puts(s, "\n"))
@@ -1046,13 +1151,14 @@ partial:
 enum print_line_t
 print_kretprobe_event(struct trace_iterator *iter, int flags)
 {
-        struct kretprobe_trace_entry *field;
+        struct kretprobe_trace_entry_head *field;
         struct trace_seq *s = &iter->seq;
         struct trace_event *event;
         struct trace_probe *tp;
+        u8 *data;
         int i;
 
-        field = (struct kretprobe_trace_entry *)iter->ent;
+        field = (struct kretprobe_trace_entry_head *)iter->ent;
         event = ftrace_find_event(field->ent.type);
         tp = container_of(event, struct trace_probe, event);
 
@@ -1071,9 +1177,10 @@ print_kretprobe_event(struct trace_iterator *iter, int flags)
         if (!trace_seq_puts(s, ")"))
                 goto partial;
 
-        for (i = 0; i < field->nargs; i++)
-                if (!trace_seq_printf(s, " %s=%lx",
-                                      tp->args[i].name, field->args[i]))
+        data = (u8 *)&field[1];
+        for (i = 0; i < tp->nr_args; i++)
+                if (!tp->args[i].type->print(s, tp->args[i].name,
+                                             data + tp->args[i].offset))
                         goto partial;
 
         if (!trace_seq_puts(s, "\n"))
@@ -1129,29 +1236,43 @@ static int probe_event_raw_init(struct ftrace_event_call *event_call)
 static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
 {
         int ret, i;
-        struct kprobe_trace_entry field;
+        struct kprobe_trace_entry_head field;
         struct trace_probe *tp = (struct trace_probe *)event_call->data;
 
         DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
-        DEFINE_FIELD(int, nargs, FIELD_STRING_NARGS, 1);
         /* Set argument names as fields */
-        for (i = 0; i < tp->nr_args; i++)
-                DEFINE_FIELD(unsigned long, args[i], tp->args[i].name, 0);
+        for (i = 0; i < tp->nr_args; i++) {
+                ret = trace_define_field(event_call, tp->args[i].type->name,
+                                         tp->args[i].name,
+                                         sizeof(field) + tp->args[i].offset,
+                                         tp->args[i].type->size,
+                                         tp->args[i].type->is_signed,
+                                         FILTER_OTHER);
+                if (ret)
+                        return ret;
+        }
         return 0;
 }
 
 static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
 {
         int ret, i;
-        struct kretprobe_trace_entry field;
+        struct kretprobe_trace_entry_head field;
         struct trace_probe *tp = (struct trace_probe *)event_call->data;
 
         DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
         DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
-        DEFINE_FIELD(int, nargs, FIELD_STRING_NARGS, 1);
         /* Set argument names as fields */
-        for (i = 0; i < tp->nr_args; i++)
-                DEFINE_FIELD(unsigned long, args[i], tp->args[i].name, 0);
+        for (i = 0; i < tp->nr_args; i++) {
+                ret = trace_define_field(event_call, tp->args[i].type->name,
+                                         tp->args[i].name,
+                                         sizeof(field) + tp->args[i].offset,
+                                         tp->args[i].type->size,
+                                         tp->args[i].type->is_signed,
+                                         FILTER_OTHER);
+                if (ret)
+                        return ret;
+        }
         return 0;
 }
 
@@ -1176,8 +1297,8 @@ static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
         pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
 
         for (i = 0; i < tp->nr_args; i++) {
-                pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%%lx",
-                                tp->args[i].name);
+                pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
+                                tp->args[i].name, tp->args[i].type->fmt);
         }
 
         pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
@@ -1219,12 +1340,13 @@ static __kprobes void kprobe_perf_func(struct kprobe *kp,
 {
         struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
         struct ftrace_event_call *call = &tp->call;
-        struct kprobe_trace_entry *entry;
+        struct kprobe_trace_entry_head *entry;
+        u8 *data;
         int size, __size, i;
         unsigned long irq_flags;
         int rctx;
 
-        __size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args);
+        __size = sizeof(*entry) + tp->size;
         size = ALIGN(__size + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
         if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
@@ -1235,10 +1357,10 @@ static __kprobes void kprobe_perf_func(struct kprobe *kp,
         if (!entry)
                 return;
 
-        entry->nargs = tp->nr_args;
         entry->ip = (unsigned long)kp->addr;
+        data = (u8 *)&entry[1];
         for (i = 0; i < tp->nr_args; i++)
-                entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
+                call_fetch(&tp->args[i].fetch, regs, data + tp->args[i].offset);
 
         perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, irq_flags, regs);
 }
@@ -1249,12 +1371,13 @@ static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
 {
         struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
         struct ftrace_event_call *call = &tp->call;
-        struct kretprobe_trace_entry *entry;
+        struct kretprobe_trace_entry_head *entry;
+        u8 *data;
         int size, __size, i;
         unsigned long irq_flags;
         int rctx;
 
-        __size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args);
+        __size = sizeof(*entry) + tp->size;
         size = ALIGN(__size + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
         if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
@@ -1265,11 +1388,11 @@ static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
         if (!entry)
                 return;
 
-        entry->nargs = tp->nr_args;
         entry->func = (unsigned long)tp->rp.kp.addr;
         entry->ret_ip = (unsigned long)ri->ret_addr;
+        data = (u8 *)&entry[1];
         for (i = 0; i < tp->nr_args; i++)
-                entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
+                call_fetch(&tp->args[i].fetch, regs, data + tp->args[i].offset);
 
         perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1,
                                irq_flags, regs);
diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c
index d59cd6879477..8eaf00749b65 100644
--- a/kernel/trace/trace_ksym.c
+++ b/kernel/trace/trace_ksym.c
@@ -34,12 +34,6 @@
 
 #include <asm/atomic.h>
 
-/*
- * For now, let us restrict the no. of symbols traced simultaneously to number
- * of available hardware breakpoint registers.
- */
-#define KSYM_TRACER_MAX HBP_NUM
-
 #define KSYM_TRACER_OP_LEN 3 /* rw- */
 
 struct trace_ksym {
@@ -53,7 +47,6 @@ struct trace_ksym {
 
 static struct trace_array *ksym_trace_array;
 
-static unsigned int ksym_filter_entry_count;
 static unsigned int ksym_tracing_enabled;
 
 static HLIST_HEAD(ksym_filter_head);
@@ -181,13 +174,6 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr)
         struct trace_ksym *entry;
         int ret = -ENOMEM;
 
-        if (ksym_filter_entry_count >= KSYM_TRACER_MAX) {
-                printk(KERN_ERR "ksym_tracer: Maximum limit:(%d) reached. No"
-                " new requests for tracing can be accepted now.\n",
-                        KSYM_TRACER_MAX);
-                return -ENOSPC;
-        }
-
         entry = kzalloc(sizeof(struct trace_ksym), GFP_KERNEL);
         if (!entry)
                 return -ENOMEM;
@@ -203,13 +189,17 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr)
 
         if (IS_ERR(entry->ksym_hbp)) {
                 ret = PTR_ERR(entry->ksym_hbp);
-                printk(KERN_INFO "ksym_tracer request failed. Try again"
-                                        " later!!\n");
+                if (ret == -ENOSPC) {
+                        printk(KERN_ERR "ksym_tracer: Maximum limit reached."
+                        " No new requests for tracing can be accepted now.\n");
+                } else {
+                        printk(KERN_INFO "ksym_tracer request failed. Try again"
+                                         " later!!\n");
+                }
                 goto err;
         }
 
         hlist_add_head_rcu(&(entry->ksym_hlist), &ksym_filter_head);
-        ksym_filter_entry_count++;
 
         return 0;
 
@@ -265,7 +255,6 @@ static void __ksym_trace_reset(void)
         hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head,
                                                                 ksym_hlist) {
                 unregister_wide_hw_breakpoint(entry->ksym_hbp);
-                ksym_filter_entry_count--;
                 hlist_del_rcu(&(entry->ksym_hlist));
                 synchronize_rcu();
                 kfree(entry);
@@ -338,7 +327,6 @@ static ssize_t ksym_trace_filter_write(struct file *file,
                                 goto out_unlock;
                 }
                 /* Error or "symbol:---" case: drop it */
-                ksym_filter_entry_count--;
                 hlist_del_rcu(&(entry->ksym_hlist));
                 synchronize_rcu();
                 kfree(entry);
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 8e46b3323cdc..ab13d7008061 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -209,6 +209,7 @@ int trace_seq_putc(struct trace_seq *s, unsigned char c)
 
         return 1;
 }
+EXPORT_SYMBOL(trace_seq_putc);
 
 int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
 {
@@ -253,7 +254,7 @@ void *trace_seq_reserve(struct trace_seq *s, size_t len)
         void *ret;
 
         if (s->full)
-                return 0;
+                return NULL;
 
         if (len > ((PAGE_SIZE - 1) - s->len)) {
                 s->full = 1;
@@ -355,6 +356,21 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 }
 EXPORT_SYMBOL(ftrace_print_symbols_seq);
 
+const char *
+ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
+{
+        int i;
+        const char *ret = p->buffer + p->len;
+
+        for (i = 0; i < buf_len; i++)
+                trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
+
+        trace_seq_putc(p, 0);
+
+        return ret;
+}
+EXPORT_SYMBOL(ftrace_print_hex_seq);
+
 #ifdef CONFIG_KRETPROBES
 static inline const char *kretprobed(const char *name)
 {
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index 5fca0f51fde4..a55fccfede5d 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -50,8 +50,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
 }
 
 static void
-probe_sched_switch(struct rq *__rq, struct task_struct *prev,
-                        struct task_struct *next)
+probe_sched_switch(struct task_struct *prev, struct task_struct *next)
 {
         struct trace_array_cpu *data;
         unsigned long flags;
@@ -109,7 +108,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
 }
 
 static void
-probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success)
+probe_sched_wakeup(struct task_struct *wakee, int success)
 {
         struct trace_array_cpu *data;
         unsigned long flags;
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 0271742abb8d..8052446ceeaa 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -107,8 +107,7 @@ static void probe_wakeup_migrate_task(struct task_struct *task, int cpu)
 }
 
 static void notrace
-probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
-        struct task_struct *next)
+probe_wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
 {
         struct trace_array_cpu *data;
         cycle_t T0, T1, delta;
@@ -200,7 +199,7 @@ static void wakeup_reset(struct trace_array *tr)
 }
 
 static void
-probe_wakeup(struct rq *rq, struct task_struct *p, int success)
+probe_wakeup(struct task_struct *p, int success)
 {
         struct trace_array_cpu *data;
         int cpu = smp_processor_id();
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 81003b4d617f..250e7f9bd2f0 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -17,7 +17,6 @@ static inline int trace_valid_entry(struct trace_entry *entry)
         case TRACE_BRANCH:
         case TRACE_GRAPH_ENT:
         case TRACE_GRAPH_RET:
-        case TRACE_HW_BRANCHES:
         case TRACE_KSYM:
                 return 1;
         }
@@ -30,7 +29,7 @@ static int trace_test_buffer_cpu(struct trace_array *tr, int cpu)
         struct trace_entry *entry;
         unsigned int loops = 0;
 
-        while ((event = ring_buffer_consume(tr->buffer, cpu, NULL))) {
+        while ((event = ring_buffer_consume(tr->buffer, cpu, NULL, NULL))) {
                 entry = ring_buffer_event_data(event);
 
                 /*
@@ -256,7 +255,8 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
 /* Maximum number of functions to trace before diagnosing a hang */
 #define GRAPH_MAX_FUNC_TEST     100000000
 
-static void __ftrace_dump(bool disable_tracing);
+static void
+__ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode);
 static unsigned int graph_hang_thresh;
 
 /* Wrap the real function entry probe to avoid possible hanging */
@@ -267,7 +267,7 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace)
                 ftrace_graph_stop();
                 printk(KERN_WARNING "BUG: Function graph tracer hang!\n");
                 if (ftrace_dump_on_oops)
-                        __ftrace_dump(false);
+                        __ftrace_dump(false, DUMP_ALL);
                 return 0;
         }
 
@@ -755,62 +755,6 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
 }
 #endif /* CONFIG_BRANCH_TRACER */
 
-#ifdef CONFIG_HW_BRANCH_TRACER
-int
-trace_selftest_startup_hw_branches(struct tracer *trace,
-                                   struct trace_array *tr)
-{
-        struct trace_iterator *iter;
-        struct tracer tracer;
-        unsigned long count;
-        int ret;
-
-        if (!trace->open) {
-                printk(KERN_CONT "missing open function...");
-                return -1;
-        }
-
-        ret = tracer_init(trace, tr);
-        if (ret) {
-                warn_failed_init_tracer(trace, ret);
-                return ret;
-        }
-
-        /*
-         * The hw-branch tracer needs to collect the trace from the various
-         * cpu trace buffers - before tracing is stopped.
-         */
-        iter = kzalloc(sizeof(*iter), GFP_KERNEL);
-        if (!iter)
-                return -ENOMEM;
-
-        memcpy(&tracer, trace, sizeof(tracer));
-
-        iter->trace = &tracer;
-        iter->tr = tr;
-        iter->pos = -1;
-        mutex_init(&iter->mutex);
-
-        trace->open(iter);
-
-        mutex_destroy(&iter->mutex);
-        kfree(iter);
-
-        tracing_stop();
-
-        ret = trace_test_buffer(tr, &count);
-        trace->reset(tr);
-        tracing_start();
-
-        if (!ret && !count) {
-                printk(KERN_CONT "no entries found..");
-                ret = -1;
-        }
-
-        return ret;
-}
-#endif /* CONFIG_HW_BRANCH_TRACER */
-
 #ifdef CONFIG_KSYM_TRACER
 static int ksym_selftest_dummy;
 
diff --git a/kernel/user.c b/kernel/user.c
index 766467b3bcb7..7e72614b736d 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -16,7 +16,6 @@
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/user_namespace.h>
-#include "cred-internals.h"
 
 struct user_namespace init_user_ns = {
         .kref = {
@@ -137,9 +136,6 @@ struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid)
         struct hlist_head *hashent = uidhashentry(ns, uid);
         struct user_struct *up, *new;
 
-        /* Make uid_hash_find() + uids_user_create() + uid_hash_insert()
-         * atomic.
-         */
         spin_lock_irq(&uidhash_lock);
         up = uid_hash_find(uid, hashent);
         spin_unlock_irq(&uidhash_lock);
@@ -161,11 +157,6 @@ struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid)
                 spin_lock_irq(&uidhash_lock);
                 up = uid_hash_find(uid, hashent);
                 if (up) {
-                        /* This case is not possible when CONFIG_USER_SCHED
-                         * is defined, since we serialize alloc_uid() using
-                         * uids_mutex. Hence no need to call
-                         * sched_destroy_user() or remove_user_sysfs_dir().
-                         */
                         key_put(new->uid_keyring);
                         key_put(new->session_keyring);
                         kmem_cache_free(uid_cachep, new);
@@ -178,8 +169,6 @@ struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid)
 
         return up;
 
-        put_user_ns(new->user_ns);
-        kmem_cache_free(uid_cachep, new);
 out_unlock:
         return NULL;
 }
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 076c7c8215b0..b2d70d38dff4 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -54,8 +54,8 @@ int create_user_ns(struct cred *new)
 #endif
         /* tgcred will be cleared in our caller bc CLONE_THREAD won't be set */
 
-        /* alloc_uid() incremented the userns refcount.  Just set it to 1 */
-        kref_set(&ns->kref, 1);
+        /* root_user holds a reference to ns, our reference can be dropped */
+        put_user_ns(ns);
 
         return 0;
 }
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5bfb213984b2..327d2deb4451 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -229,6 +229,16 @@ static inline void set_wq_data(struct work_struct *work,
         atomic_long_set(&work->data, new);
 }
 
+/*
+ * Clear WORK_STRUCT_PENDING and the workqueue on which it was queued.
+ */
+static inline void clear_wq_data(struct work_struct *work)
+{
+        unsigned long flags = *work_data_bits(work) &
+                                (1UL << WORK_STRUCT_STATIC);
+        atomic_long_set(&work->data, flags);
+}
+
 static inline
 struct cpu_workqueue_struct *get_wq_data(struct work_struct *work)
 {
@@ -671,7 +681,7 @@ static int __cancel_work_timer(struct work_struct *work,
                 wait_on_work(work);
         } while (unlikely(ret < 0));
 
-        work_clear_pending(work);
+        clear_wq_data(work);
         return ret;
 }
 
@@ -845,6 +855,30 @@ int schedule_on_each_cpu(work_func_t func)
         return 0;
 }
 
+/**
+ * flush_scheduled_work - ensure that any scheduled work has run to completion.
+ *
+ * Forces execution of the kernel-global workqueue and blocks until its
+ * completion.
+ *
+ * Think twice before calling this function!  It's very easy to get into
+ * trouble if you don't take great care.  Either of the following situations
+ * will lead to deadlock:
+ *
+ *      One of the work items currently on the workqueue needs to acquire
+ *      a lock held by your code or its caller.
+ *
+ *      Your code is running in the context of a work routine.
+ *
+ * They will be detected by lockdep when they occur, but the first might not
+ * occur very often.  It depends on what work items are on the workqueue and
+ * what locks they need, which you have no control over.
+ *
+ * In most situations flushing the entire workqueue is overkill; you merely
+ * need to know that a particular work item isn't queued and isn't running.
+ * In such cases you should use cancel_delayed_work_sync() or
+ * cancel_work_sync() instead.
+ */
 void flush_scheduled_work(void)
 {
         flush_workqueue(keventd_wq);
@@ -1076,7 +1110,7 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb,
         unsigned int cpu = (unsigned long)hcpu;
         struct cpu_workqueue_struct *cwq;
         struct workqueue_struct *wq;
-        int ret = NOTIFY_OK;
+        int err = 0;
 
         action &= ~CPU_TASKS_FROZEN;
 
@@ -1090,12 +1124,13 @@ undo:
 
                 switch (action) {
                 case CPU_UP_PREPARE:
-                        if (!create_workqueue_thread(cwq, cpu))
+                        err = create_workqueue_thread(cwq, cpu);
+                        if (!err)
                                 break;
                         printk(KERN_ERR "workqueue [%s] for %i failed\n",
                                 wq->name, cpu);
                         action = CPU_UP_CANCELED;
-                        ret = NOTIFY_BAD;
+                        err = -ENOMEM;
                         goto undo;
 
                 case CPU_ONLINE:
@@ -1116,7 +1151,7 @@ undo:
                 cpumask_clear_cpu(cpu, cpu_populated_map);
         }
 
-        return ret;
+        return notifier_from_errno(err);
 }
 
 #ifdef CONFIG_SMP