14 files changed, 604 insertions, 203 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 1143012951e9..6f50ef55a6f3 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -971,7 +971,7 @@ NORET_TYPE void do_exit(long code)
         exit_thread();
         cgroup_exit(tsk, 1);
 
-        if (group_dead && tsk->signal->leader)
+        if (group_dead)
                 disassociate_ctty(1);
 
         module_put(task_thread_info(tsk)->exec_domain->module);
diff --git a/kernel/futex.c b/kernel/futex.c
index fb65e822fc41..d73ef1f3e55d 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -304,8 +304,14 @@ void put_futex_key(int fshared, union futex_key *key)
  */
 static int fault_in_user_writeable(u32 __user *uaddr)
 {
-        int ret = get_user_pages(current, current->mm, (unsigned long)uaddr,
-                                 1, 1, 0, NULL, NULL);
+        struct mm_struct *mm = current->mm;
+        int ret;
+
+        down_read(&mm->mmap_sem);
+        ret = get_user_pages(current, mm, (unsigned long)uaddr,
+                             1, 1, 0, NULL, NULL);
+        up_read(&mm->mmap_sem);
+
         return ret < 0 ? ret : 0;
 }
 
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index cf5ee1628411..366eedf949c0 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -52,7 +52,7 @@
 static DEFINE_PER_CPU(unsigned int, nr_cpu_bp_pinned);
 
 /* Number of pinned task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, task_bp_pinned[HBP_NUM]);
+static DEFINE_PER_CPU(unsigned int, nr_task_bp_pinned[HBP_NUM]);
 
 /* Number of non-pinned cpu/task breakpoints in a cpu */
 static DEFINE_PER_CPU(unsigned int, nr_bp_flexible);
@@ -73,7 +73,7 @@ static DEFINE_MUTEX(nr_bp_mutex);
 static unsigned int max_task_bp_pinned(int cpu)
 {
         int i;
-        unsigned int *tsk_pinned = per_cpu(task_bp_pinned, cpu);
+        unsigned int *tsk_pinned = per_cpu(nr_task_bp_pinned, cpu);
 
         for (i = HBP_NUM -1; i >= 0; i--) {
                 if (tsk_pinned[i] > 0)
@@ -83,15 +83,51 @@ static unsigned int max_task_bp_pinned(int cpu)
         return 0;
 }
 
+static int task_bp_pinned(struct task_struct *tsk)
+{
+        struct perf_event_context *ctx = tsk->perf_event_ctxp;
+        struct list_head *list;
+        struct perf_event *bp;
+        unsigned long flags;
+        int count = 0;
+
+        if (WARN_ONCE(!ctx, "No perf context for this task"))
+                return 0;
+
+        list = &ctx->event_list;
+
+        spin_lock_irqsave(&ctx->lock, flags);
+
+        /*
+         * The current breakpoint counter is not included in the list
+         * at the open() callback time
+         */
+        list_for_each_entry(bp, list, event_entry) {
+                if (bp->attr.type == PERF_TYPE_BREAKPOINT)
+                        count++;
+        }
+
+        spin_unlock_irqrestore(&ctx->lock, flags);
+
+        return count;
+}
+
 /*
  * Report the number of pinned/un-pinned breakpoints we have in
  * a given cpu (cpu > -1) or in all of them (cpu = -1).
  */
-static void fetch_bp_busy_slots(struct bp_busy_slots *slots, int cpu)
+static void
+fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp)
 {
+        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 += max_task_bp_pinned(cpu);
+                if (!tsk)
+                        slots->pinned += max_task_bp_pinned(cpu);
+                else
+                        slots->pinned += task_bp_pinned(tsk);
                 slots->flexible = per_cpu(nr_bp_flexible, cpu);
 
                 return;
@@ -101,7 +137,10 @@ static void fetch_bp_busy_slots(struct bp_busy_slots *slots, int cpu)
                 unsigned int nr;
 
                 nr = per_cpu(nr_cpu_bp_pinned, cpu);
-                nr += max_task_bp_pinned(cpu);
+                if (!tsk)
+                        nr += max_task_bp_pinned(cpu);
+                else
+                        nr += task_bp_pinned(tsk);
 
                 if (nr > slots->pinned)
                         slots->pinned = nr;
@@ -118,35 +157,12 @@ static void fetch_bp_busy_slots(struct bp_busy_slots *slots, int cpu)
  */
 static void toggle_bp_task_slot(struct task_struct *tsk, int cpu, bool enable)
 {
-        int count = 0;
-        struct perf_event *bp;
-        struct perf_event_context *ctx = tsk->perf_event_ctxp;
         unsigned int *tsk_pinned;
-        struct list_head *list;
-        unsigned long flags;
-
-        if (WARN_ONCE(!ctx, "No perf context for this task"))
-                return;
-
-        list = &ctx->event_list;
-
-        spin_lock_irqsave(&ctx->lock, flags);
-
-        /*
-         * The current breakpoint counter is not included in the list
-         * at the open() callback time
-         */
-        list_for_each_entry(bp, list, event_entry) {
-                if (bp->attr.type == PERF_TYPE_BREAKPOINT)
-                        count++;
-        }
+        int count = 0;
 
-        spin_unlock_irqrestore(&ctx->lock, flags);
+        count = task_bp_pinned(tsk);
 
-        if (WARN_ONCE(count < 0, "No breakpoint counter found in the counter list"))
-                return;
-
-        tsk_pinned = per_cpu(task_bp_pinned, cpu);
+        tsk_pinned = per_cpu(nr_task_bp_pinned, cpu);
         if (enable) {
                 tsk_pinned[count]++;
                 if (count > 0)
@@ -193,7 +209,7 @@ static void toggle_bp_slot(struct perf_event *bp, bool enable)
  *   - If attached to a single cpu, check:
  *
  *       (per_cpu(nr_bp_flexible, cpu) || (per_cpu(nr_cpu_bp_pinned, cpu)
- *           + max(per_cpu(task_bp_pinned, cpu)))) < HBP_NUM
+ *           + max(per_cpu(nr_task_bp_pinned, cpu)))) < HBP_NUM
  *
  *       -> If there are already non-pinned counters in this cpu, it means
  *          there is already a free slot for them.
@@ -204,7 +220,7 @@ static void toggle_bp_slot(struct perf_event *bp, bool enable)
  *   - If attached to every cpus, check:
  *
  *       (per_cpu(nr_bp_flexible, *) || (max(per_cpu(nr_cpu_bp_pinned, *))
- *           + max(per_cpu(task_bp_pinned, *)))) < HBP_NUM
+ *           + max(per_cpu(nr_task_bp_pinned, *)))) < HBP_NUM
  *
  *       -> This is roughly the same, except we check the number of per cpu
  *          bp for every cpu and we keep the max one. Same for the per tasks
@@ -216,7 +232,7 @@ static void toggle_bp_slot(struct perf_event *bp, bool enable)
  *   - If attached to a single cpu, check:
  *
  *       ((per_cpu(nr_bp_flexible, cpu) > 1) + per_cpu(nr_cpu_bp_pinned, cpu)
- *            + max(per_cpu(task_bp_pinned, cpu))) < HBP_NUM
+ *            + max(per_cpu(nr_task_bp_pinned, cpu))) < HBP_NUM
  *
  *       -> Same checks as before. But now the nr_bp_flexible, if any, must keep
  *          one register at least (or they will never be fed).
@@ -224,7 +240,7 @@ static void toggle_bp_slot(struct perf_event *bp, bool enable)
  *   - If attached to every cpus, check:
  *
  *       ((per_cpu(nr_bp_flexible, *) > 1) + max(per_cpu(nr_cpu_bp_pinned, *))
- *            + max(per_cpu(task_bp_pinned, *))) < HBP_NUM
+ *            + max(per_cpu(nr_task_bp_pinned, *))) < HBP_NUM
  */
 int reserve_bp_slot(struct perf_event *bp)
 {
@@ -233,7 +249,7 @@ int reserve_bp_slot(struct perf_event *bp)
 
         mutex_lock(&nr_bp_mutex);
 
-        fetch_bp_busy_slots(&slots, bp->cpu);
+        fetch_bp_busy_slots(&slots, bp);
 
         /* Flexible counters need to keep at least one slot */
         if (slots.pinned + (!!slots.flexible) == HBP_NUM) {
@@ -259,7 +275,7 @@ void release_bp_slot(struct perf_event *bp)
 }
 
 
-int __register_perf_hw_breakpoint(struct perf_event *bp)
+int register_perf_hw_breakpoint(struct perf_event *bp)
 {
         int ret;
 
@@ -276,19 +292,12 @@ int __register_perf_hw_breakpoint(struct perf_event *bp)
          * This is a quick hack that will be removed soon, once we remove
          * the tmp breakpoints from ptrace
          */
-        if (!bp->attr.disabled || bp->callback == perf_bp_event)
+        if (!bp->attr.disabled || !bp->overflow_handler)
                 ret = arch_validate_hwbkpt_settings(bp, bp->ctx->task);
 
         return ret;
 }
 
-int register_perf_hw_breakpoint(struct perf_event *bp)
-{
-        bp->callback = perf_bp_event;
-
-        return __register_perf_hw_breakpoint(bp);
-}
-
 /**
  * register_user_hw_breakpoint - register a hardware breakpoint for user space
  * @attr: breakpoint attributes
@@ -297,7 +306,7 @@ int register_perf_hw_breakpoint(struct perf_event *bp)
  */
 struct perf_event *
 register_user_hw_breakpoint(struct perf_event_attr *attr,
-                            perf_callback_t triggered,
+                            perf_overflow_handler_t triggered,
                             struct task_struct *tsk)
 {
         return perf_event_create_kernel_counter(attr, -1, tsk->pid, triggered);
@@ -311,19 +320,40 @@ EXPORT_SYMBOL_GPL(register_user_hw_breakpoint);
  * @triggered: callback to trigger when we hit the breakpoint
  * @tsk: pointer to 'task_struct' of the process to which the address belongs
  */
-struct perf_event *
-modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr,
-                          perf_callback_t triggered,
-                          struct task_struct *tsk)
+int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr)
 {
-        /*
-         * FIXME: do it without unregistering
-         * - We don't want to lose our slot
-         * - If the new bp is incorrect, don't lose the older one
-         */
-        unregister_hw_breakpoint(bp);
+        u64 old_addr = bp->attr.bp_addr;
+        int old_type = bp->attr.bp_type;
+        int old_len = bp->attr.bp_len;
+        int err = 0;
 
-        return perf_event_create_kernel_counter(attr, -1, tsk->pid, triggered);
+        perf_event_disable(bp);
+
+        bp->attr.bp_addr = attr->bp_addr;
+        bp->attr.bp_type = attr->bp_type;
+        bp->attr.bp_len = attr->bp_len;
+
+        if (attr->disabled)
+                goto end;
+
+        err = arch_validate_hwbkpt_settings(bp, bp->ctx->task);
+        if (!err)
+                perf_event_enable(bp);
+
+        if (err) {
+                bp->attr.bp_addr = old_addr;
+                bp->attr.bp_type = old_type;
+                bp->attr.bp_len = old_len;
+                if (!bp->attr.disabled)
+                        perf_event_enable(bp);
+
+                return err;
+        }
+
+end:
+        bp->attr.disabled = attr->disabled;
+
+        return 0;
 }
 EXPORT_SYMBOL_GPL(modify_user_hw_breakpoint);
 
@@ -348,7 +378,7 @@ EXPORT_SYMBOL_GPL(unregister_hw_breakpoint);
  */
 struct perf_event **
 register_wide_hw_breakpoint(struct perf_event_attr *attr,
-                            perf_callback_t triggered)
+                            perf_overflow_handler_t triggered)
 {
         struct perf_event **cpu_events, **pevent, *bp;
         long err;
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
index 7d7014634022..2eb517e23514 100644
--- a/kernel/kgdb.c
+++ b/kernel/kgdb.c
@@ -129,6 +129,7 @@ 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];
@@ -541,12 +542,17 @@ static struct task_struct *getthread(struct pt_regs *regs, int tid)
          */
         if (tid == 0 || tid == -1)
                 tid = -atomic_read(&kgdb_active) - 2;
-        if (tid < 0) {
+        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
@@ -619,7 +625,8 @@ static void kgdb_flush_swbreak_addr(unsigned long addr)
 static int kgdb_activate_sw_breakpoints(void)
 {
         unsigned long addr;
-        int error = 0;
+        int error;
+        int ret = 0;
         int i;
 
         for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
@@ -629,13 +636,16 @@ static int kgdb_activate_sw_breakpoints(void)
                 addr = kgdb_break[i].bpt_addr;
                 error = kgdb_arch_set_breakpoint(addr,
                                 kgdb_break[i].saved_instr);
-                if (error)
-                        return error;
+                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 0;
+        return ret;
 }
 
 static int kgdb_set_sw_break(unsigned long addr)
@@ -682,7 +692,8 @@ static int kgdb_set_sw_break(unsigned long addr)
 static int kgdb_deactivate_sw_breakpoints(void)
 {
         unsigned long addr;
-        int error = 0;
+        int error;
+        int ret = 0;
         int i;
 
         for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
@@ -691,13 +702,15 @@ static int kgdb_deactivate_sw_breakpoints(void)
                 addr = kgdb_break[i].bpt_addr;
                 error = kgdb_arch_remove_breakpoint(addr,
                                         kgdb_break[i].saved_instr);
-                if (error)
-                        return error;
+                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 0;
+        return ret;
 }
 
 static int kgdb_remove_sw_break(unsigned long addr)
@@ -1204,8 +1217,10 @@ static int gdb_cmd_exception_pass(struct kgdb_state *ks)
                 return 1;
 
         } else {
-                error_packet(remcom_out_buffer, -EINVAL);
-                return 0;
+                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 */
@@ -1395,6 +1410,7 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
         struct kgdb_state kgdb_var;
         struct kgdb_state *ks = &kgdb_var;
         unsigned long flags;
+        int sstep_tries = 100;
         int error = 0;
         int i, cpu;
 
@@ -1425,13 +1441,14 @@ acquirelock:
                 cpu_relax();
 
         /*
-         * Do not start the debugger connection on this CPU if the last
-         * instance of the exception handler wanted to come into the
-         * debugger on a different CPU via a single step
+         * 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 &&
-            atomic_read(&kgdb_cpu_doing_single_step) != cpu) {
-
+            (kgdb_info[cpu].task &&
+             kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) {
                 atomic_set(&kgdb_active, -1);
                 touch_softlockup_watchdog();
                 clocksource_touch_watchdog();
@@ -1524,6 +1541,13 @@ acquirelock:
         }
 
 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;
+        }
         /* Free kgdb_active */
         atomic_set(&kgdb_active, -1);
         touch_softlockup_watchdog();
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index f5dcd36d3151..4f8df01dbe51 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -168,7 +168,7 @@ static void lock_time_inc(struct lock_time *lt, u64 time)
         if (time > lt->max)
                 lt->max = time;
 
-        if (time < lt->min || !lt->min)
+        if (time < lt->min || !lt->nr)
                 lt->min = time;
 
         lt->total += time;
@@ -177,8 +177,15 @@ static void lock_time_inc(struct lock_time *lt, u64 time)
 
 static inline void lock_time_add(struct lock_time *src, struct lock_time *dst)
 {
-        dst->min += src->min;
-        dst->max += src->max;
+        if (!src->nr)
+                return;
+
+        if (src->max > dst->max)
+                dst->max = src->max;
+
+        if (src->min < dst->min || !dst->nr)
+                dst->min = src->min;
+
         dst->total += src->total;
         dst->nr += src->nr;
 }
@@ -379,7 +386,8 @@ static int save_trace(struct stack_trace *trace)
          * complete trace that maxes out the entries provided will be reported
          * as incomplete, friggin useless </rant>
          */
-        if (trace->entries[trace->nr_entries-1] == ULONG_MAX)
+        if (trace->nr_entries != 0 &&
+            trace->entries[trace->nr_entries-1] == ULONG_MAX)
                 trace->nr_entries--;
 
         trace->max_entries = trace->nr_entries;
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 40a996ec39fa..e73e53c7582f 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -36,7 +36,7 @@
 /*
  * Each CPU has a list of per CPU events:
  */
-DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context);
+static DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context);
 
 int perf_max_events __read_mostly = 1;
 static int perf_reserved_percpu __read_mostly;
@@ -567,7 +567,7 @@ static void __perf_event_disable(void *info)
  * is the current context on this CPU and preemption is disabled,
  * hence we can't get into perf_event_task_sched_out for this context.
  */
-static void perf_event_disable(struct perf_event *event)
+void perf_event_disable(struct perf_event *event)
 {
         struct perf_event_context *ctx = event->ctx;
         struct task_struct *task = ctx->task;
@@ -971,7 +971,7 @@ static void __perf_event_enable(void *info)
  * perf_event_for_each_child or perf_event_for_each as described
  * for perf_event_disable.
  */
-static void perf_event_enable(struct perf_event *event)
+void perf_event_enable(struct perf_event *event)
 {
         struct perf_event_context *ctx = event->ctx;
         struct task_struct *task = ctx->task;
@@ -1579,7 +1579,6 @@ static void
 __perf_event_init_context(struct perf_event_context *ctx,
                             struct task_struct *task)
 {
-        memset(ctx, 0, sizeof(*ctx));
         spin_lock_init(&ctx->lock);
         mutex_init(&ctx->mutex);
         INIT_LIST_HEAD(&ctx->group_list);
@@ -1654,7 +1653,7 @@ static struct perf_event_context *find_get_context(pid_t pid, int cpu)
         }
 
         if (!ctx) {
-                ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL);
+                ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL);
                 err = -ENOMEM;
                 if (!ctx)
                         goto errout;
@@ -4011,6 +4010,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
         event->pmu->read(event);
 
         data.addr = 0;
+        data.raw = NULL;
         data.period = event->hw.last_period;
         regs = get_irq_regs();
         /*
@@ -4080,8 +4080,7 @@ static void cpu_clock_perf_event_update(struct perf_event *event)
         u64 now;
 
         now = cpu_clock(cpu);
-        prev = atomic64_read(&event->hw.prev_count);
-        atomic64_set(&event->hw.prev_count, now);
+        prev = atomic64_xchg(&event->hw.prev_count, now);
         atomic64_add(now - prev, &event->count);
 }
 
@@ -4286,15 +4285,8 @@ static void bp_perf_event_destroy(struct perf_event *event)
 static const struct pmu *bp_perf_event_init(struct perf_event *bp)
 {
         int err;
-        /*
-         * The breakpoint is already filled if we haven't created the counter
-         * through perf syscall
-         * FIXME: manage to get trigerred to NULL if it comes from syscalls
-         */
-        if (!bp->callback)
-                err = register_perf_hw_breakpoint(bp);
-        else
-                err = __register_perf_hw_breakpoint(bp);
+
+        err = register_perf_hw_breakpoint(bp);
         if (err)
                 return ERR_PTR(err);
 
@@ -4308,6 +4300,7 @@ void perf_bp_event(struct perf_event *bp, void *data)
         struct perf_sample_data sample;
         struct pt_regs *regs = data;
 
+        sample.raw = NULL;
         sample.addr = bp->attr.bp_addr;
 
         if (!perf_exclude_event(bp, regs))
@@ -4390,7 +4383,7 @@ perf_event_alloc(struct perf_event_attr *attr,
                    struct perf_event_context *ctx,
                    struct perf_event *group_leader,
                    struct perf_event *parent_event,
-                   perf_callback_t callback,
+                   perf_overflow_handler_t overflow_handler,
                    gfp_t gfpflags)
 {
         const struct pmu *pmu;
@@ -4433,10 +4426,10 @@ perf_event_alloc(struct perf_event_attr *attr,
 
         event->state            = PERF_EVENT_STATE_INACTIVE;
 
-        if (!callback && parent_event)
-                callback = parent_event->callback;
+        if (!overflow_handler && parent_event)
+                overflow_handler = parent_event->overflow_handler;
         
-        event->callback = callback;
+        event->overflow_handler = overflow_handler;
 
         if (attr->disabled)
                 event->state = PERF_EVENT_STATE_OFF;
@@ -4776,7 +4769,8 @@ err_put_context:
  */
 struct perf_event *
 perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
-                                 pid_t pid, perf_callback_t callback)
+                                 pid_t pid,
+                                 perf_overflow_handler_t overflow_handler)
 {
         struct perf_event *event;
         struct perf_event_context *ctx;
@@ -4793,7 +4787,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
         }
 
         event = perf_event_alloc(attr, cpu, ctx, NULL,
-                                     NULL, callback, GFP_KERNEL);
+                                 NULL, overflow_handler, GFP_KERNEL);
         if (IS_ERR(event)) {
                 err = PTR_ERR(event);
                 goto err_put_context;
@@ -5090,7 +5084,7 @@ again:
  */
 int perf_event_init_task(struct task_struct *child)
 {
-        struct perf_event_context *child_ctx, *parent_ctx;
+        struct perf_event_context *child_ctx = NULL, *parent_ctx;
         struct perf_event_context *cloned_ctx;
         struct perf_event *event;
         struct task_struct *parent = current;
@@ -5106,20 +5100,6 @@ int perf_event_init_task(struct task_struct *child)
                 return 0;
 
         /*
-         * This is executed from the parent task context, so inherit
-         * events that have been marked for cloning.
-         * First allocate and initialize a context for the child.
-         */
-
-        child_ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL);
-        if (!child_ctx)
-                return -ENOMEM;
-
-        __perf_event_init_context(child_ctx, child);
-        child->perf_event_ctxp = child_ctx;
-        get_task_struct(child);
-
-        /*
          * If the parent's context is a clone, pin it so it won't get
          * swapped under us.
          */
@@ -5149,6 +5129,26 @@ int perf_event_init_task(struct task_struct *child)
                         continue;
                 }
 
+                if (!child->perf_event_ctxp) {
+                        /*
+                         * This is executed from the parent task context, so
+                         * inherit events that have been marked for cloning.
+                         * First allocate and initialize a context for the
+                         * child.
+                         */
+
+                        child_ctx = kzalloc(sizeof(struct perf_event_context),
+                                            GFP_KERNEL);
+                        if (!child_ctx) {
+                                ret = -ENOMEM;
+                                goto exit;
+                        }
+
+                        __perf_event_init_context(child_ctx, child);
+                        child->perf_event_ctxp = child_ctx;
+                        get_task_struct(child);
+                }
+
                 ret = inherit_group(event, parent, parent_ctx,
                                              child, child_ctx);
                 if (ret) {
@@ -5177,6 +5177,7 @@ int perf_event_init_task(struct task_struct *child)
                 get_ctx(child_ctx->parent_ctx);
         }
 
+exit:
         mutex_unlock(&parent_ctx->mutex);
 
         perf_unpin_context(parent_ctx);
diff --git a/kernel/resource.c b/kernel/resource.c
index fb11a58b9594..dc15686b7a77 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -308,35 +308,37 @@ static int find_resource(struct resource *root, struct resource *new,
                          void *alignf_data)
 {
         struct resource *this = root->child;
+        resource_size_t start, end;
 
-        new->start = root->start;
+        start = root->start;
         /*
          * Skip past an allocated resource that starts at 0, since the assignment
          * of this->start - 1 to new->end below would cause an underflow.
          */
         if (this && this->start == 0) {
-                new->start = this->end + 1;
+                start = this->end + 1;
                 this = this->sibling;
         }
         for(;;) {
                 if (this)
-                        new->end = this->start - 1;
+                        end = this->start - 1;
                 else
-                        new->end = root->end;
-                if (new->start < min)
-                        new->start = min;
-                if (new->end > max)
-                        new->end = max;
-                new->start = ALIGN(new->start, align);
+                        end = root->end;
+                if (start < min)
+                        start = min;
+                if (end > max)
+                        end = max;
+                start = ALIGN(start, align);
                 if (alignf)
                         alignf(alignf_data, new, size, align);
-                if (new->start < new->end && new->end - new->start >= size - 1) {
-                        new->end = new->start + size - 1;
+                if (start < end && end - start >= size - 1) {
+                        new->start = start;
+                        new->end = start + size - 1;
                         return 0;
                 }
                 if (!this)
                         break;
-                new->start = this->end + 1;
+                start = this->end + 1;
                 this = this->sibling;
         }
         return -EBUSY;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 874f2893cff0..88bd9ae2a9ed 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1361,11 +1361,7 @@ int trace_array_vprintk(struct trace_array *tr,
         pause_graph_tracing();
         raw_local_irq_save(irq_flags);
         __raw_spin_lock(&trace_buf_lock);
-        if (args == NULL) {
-                strncpy(trace_buf, fmt, TRACE_BUF_SIZE);
-                len = strlen(trace_buf);
-        } else
-                len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args);
+        len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args);
 
         size = sizeof(*entry) + len + 1;
         buffer = tr->buffer;
@@ -1516,6 +1512,8 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos)
         int i = (int)*pos;
         void *ent;
 
+        WARN_ON_ONCE(iter->leftover);
+
         (*pos)++;
 
         /* can't go backwards */
@@ -1614,8 +1612,16 @@ static void *s_start(struct seq_file *m, loff_t *pos)
                         ;
 
         } else {
-                l = *pos - 1;
-                p = s_next(m, p, &l);
+                /*
+                 * If we overflowed the seq_file before, then we want
+                 * to just reuse the trace_seq buffer again.
+                 */
+                if (iter->leftover)
+                        p = iter;
+                else {
+                        l = *pos - 1;
+                        p = s_next(m, p, &l);
+                }
         }
 
         trace_event_read_lock();
@@ -1923,6 +1929,7 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter)
 static int s_show(struct seq_file *m, void *v)
 {
         struct trace_iterator *iter = v;
+        int ret;
 
         if (iter->ent == NULL) {
                 if (iter->tr) {
@@ -1942,9 +1949,27 @@ static int s_show(struct seq_file *m, void *v)
                         if (!(trace_flags & TRACE_ITER_VERBOSE))
                                 print_func_help_header(m);
                 }
+        } else if (iter->leftover) {
+                /*
+                 * If we filled the seq_file buffer earlier, we
+                 * want to just show it now.
+                 */
+                ret = trace_print_seq(m, &iter->seq);
+
+                /* ret should this time be zero, but you never know */
+                iter->leftover = ret;
+
         } else {
                 print_trace_line(iter);
-                trace_print_seq(m, &iter->seq);
+                ret = trace_print_seq(m, &iter->seq);
+                /*
+                 * If we overflow the seq_file buffer, then it will
+                 * ask us for this data again at start up.
+                 * Use that instead.
+                 *  ret is 0 if seq_file write succeeded.
+                 *        -1 otherwise.
+                 */
+                iter->leftover = ret;
         }
 
         return 0;
@@ -2898,6 +2923,10 @@ static int tracing_release_pipe(struct inode *inode, struct file *file)
         else
                 cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask);
 
+
+        if (iter->trace->pipe_close)
+                iter->trace->pipe_close(iter);
+
         mutex_unlock(&trace_types_lock);
 
         free_cpumask_var(iter->started);
@@ -3320,6 +3349,16 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
         return cnt;
 }
 
+static int mark_printk(const char *fmt, ...)
+{
+        int ret;
+        va_list args;
+        va_start(args, fmt);
+        ret = trace_vprintk(0, fmt, args);
+        va_end(args);
+        return ret;
+}
+
 static ssize_t
 tracing_mark_write(struct file *filp, const char __user *ubuf,
                                         size_t cnt, loff_t *fpos)
@@ -3346,7 +3385,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
         } else
                 buf[cnt] = '\0';
 
-        cnt = trace_vprintk(0, buf, NULL);
+        cnt = mark_printk("%s", buf);
         kfree(buf);
         *fpos += cnt;
 
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 1d7f4830a80d..7fa33cab6962 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -272,6 +272,7 @@ struct tracer_flags {
  * @pipe_open: called when the trace_pipe file is opened
  * @wait_pipe: override how the user waits for traces on trace_pipe
  * @close: called when the trace file is released
+ * @pipe_close: called when the trace_pipe file is released
  * @read: override the default read callback on trace_pipe
  * @splice_read: override the default splice_read callback on trace_pipe
  * @selftest: selftest to run on boot (see trace_selftest.c)
@@ -290,6 +291,7 @@ struct tracer {
         void                    (*pipe_open)(struct trace_iterator *iter);
         void                    (*wait_pipe)(struct trace_iterator *iter);
         void                    (*close)(struct trace_iterator *iter);
+        void                    (*pipe_close)(struct trace_iterator *iter);
         ssize_t                 (*read)(struct trace_iterator *iter,
                                         struct file *filp, char __user *ubuf,
                                         size_t cnt, loff_t *ppos);
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 45e6c01b2e4d..a43d009c561a 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -14,9 +14,20 @@
 #include "trace.h"
 #include "trace_output.h"
 
-struct fgraph_data {
+struct fgraph_cpu_data {
         pid_t           last_pid;
         int             depth;
+        int             ignore;
+};
+
+struct fgraph_data {
+        struct fgraph_cpu_data          *cpu_data;
+
+        /* Place to preserve last processed entry. */
+        struct ftrace_graph_ent_entry   ent;
+        struct ftrace_graph_ret_entry   ret;
+        int                             failed;
+        int                             cpu;
 };
 
 #define TRACE_GRAPH_INDENT      2
@@ -384,7 +395,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
         if (!data)
                 return TRACE_TYPE_HANDLED;
 
-        last_pid = &(per_cpu_ptr(data, cpu)->last_pid);
+        last_pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid);
 
         if (*last_pid == pid)
                 return TRACE_TYPE_HANDLED;
@@ -435,26 +446,49 @@ static struct ftrace_graph_ret_entry *
 get_return_for_leaf(struct trace_iterator *iter,
                 struct ftrace_graph_ent_entry *curr)
 {
-        struct ring_buffer_iter *ring_iter;
+        struct fgraph_data *data = iter->private;
+        struct ring_buffer_iter *ring_iter = NULL;
         struct ring_buffer_event *event;
         struct ftrace_graph_ret_entry *next;
 
-        ring_iter = iter->buffer_iter[iter->cpu];
+        /*
+         * If the previous output failed to write to the seq buffer,
+         * then we just reuse the data from before.
+         */
+        if (data && data->failed) {
+                curr = &data->ent;
+                next = &data->ret;
+        } else {
 
-        /* First peek to compare current entry and the next one */
-        if (ring_iter)
-                event = ring_buffer_iter_peek(ring_iter, NULL);
-        else {
-        /* We need to consume the current entry to see the next one */
-                ring_buffer_consume(iter->tr->buffer, iter->cpu, NULL);
-                event = ring_buffer_peek(iter->tr->buffer, iter->cpu,
-                                        NULL);
-        }
+                ring_iter = iter->buffer_iter[iter->cpu];
+
+                /* First peek to compare current entry and the next one */
+                if (ring_iter)
+                        event = ring_buffer_iter_peek(ring_iter, NULL);
+                else {
+                        /*
+                         * We need to consume the current entry to see
+                         * the next one.
+                         */
+                        ring_buffer_consume(iter->tr->buffer, iter->cpu, NULL);
+                        event = ring_buffer_peek(iter->tr->buffer, iter->cpu,
+                                                 NULL);
+                }
 
-        if (!event)
-                return NULL;
+                if (!event)
+                        return NULL;
+
+                next = ring_buffer_event_data(event);
 
-        next = ring_buffer_event_data(event);
+                if (data) {
+                        /*
+                         * Save current and next entries for later reference
+                         * if the output fails.
+                         */
+                        data->ent = *curr;
+                        data->ret = *next;
+                }
+        }
 
         if (next->ent.type != TRACE_GRAPH_RET)
                 return NULL;
@@ -640,7 +674,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
 
         if (data) {
                 int cpu = iter->cpu;
-                int *depth = &(per_cpu_ptr(data, cpu)->depth);
+                int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
 
                 /*
                  * Comments display at + 1 to depth. Since
@@ -688,7 +722,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
 
         if (data) {
                 int cpu = iter->cpu;
-                int *depth = &(per_cpu_ptr(data, cpu)->depth);
+                int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
 
                 *depth = call->depth;
         }
@@ -782,19 +816,34 @@ static enum print_line_t
 print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
                         struct trace_iterator *iter)
 {
-        int cpu = iter->cpu;
+        struct fgraph_data *data = iter->private;
         struct ftrace_graph_ent *call = &field->graph_ent;
         struct ftrace_graph_ret_entry *leaf_ret;
+        static enum print_line_t ret;
+        int cpu = iter->cpu;
 
         if (print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func))
                 return TRACE_TYPE_PARTIAL_LINE;
 
         leaf_ret = get_return_for_leaf(iter, field);
         if (leaf_ret)
-                return print_graph_entry_leaf(iter, field, leaf_ret, s);
+                ret = print_graph_entry_leaf(iter, field, leaf_ret, s);
         else
-                return print_graph_entry_nested(iter, field, s, cpu);
+                ret = print_graph_entry_nested(iter, field, s, cpu);
 
+        if (data) {
+                /*
+                 * If we failed to write our output, then we need to make
+                 * note of it. Because we already consumed our entry.
+                 */
+                if (s->full) {
+                        data->failed = 1;
+                        data->cpu = cpu;
+                } else
+                        data->failed = 0;
+        }
+
+        return ret;
 }
 
 static enum print_line_t
@@ -810,7 +859,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
 
         if (data) {
                 int cpu = iter->cpu;
-                int *depth = &(per_cpu_ptr(data, cpu)->depth);
+                int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
 
                 /*
                  * Comments display at + 1 to depth. This is the
@@ -873,7 +922,7 @@ print_graph_comment(struct trace_seq *s,  struct trace_entry *ent,
         int i;
 
         if (data)
-                depth = per_cpu_ptr(data, iter->cpu)->depth;
+                depth = per_cpu_ptr(data->cpu_data, iter->cpu)->depth;
 
         if (print_graph_prologue(iter, s, 0, 0))
                 return TRACE_TYPE_PARTIAL_LINE;
@@ -941,8 +990,33 @@ print_graph_comment(struct trace_seq *s,  struct trace_entry *ent,
 enum print_line_t
 print_graph_function(struct trace_iterator *iter)
 {
+        struct ftrace_graph_ent_entry *field;
+        struct fgraph_data *data = iter->private;
         struct trace_entry *entry = iter->ent;
         struct trace_seq *s = &iter->seq;
+        int cpu = iter->cpu;
+        int ret;
+
+        if (data && per_cpu_ptr(data->cpu_data, cpu)->ignore) {
+                per_cpu_ptr(data->cpu_data, cpu)->ignore = 0;
+                return TRACE_TYPE_HANDLED;
+        }
+
+        /*
+         * If the last output failed, there's a possibility we need
+         * to print out the missing entry which would never go out.
+         */
+        if (data && data->failed) {
+                field = &data->ent;
+                iter->cpu = data->cpu;
+                ret = print_graph_entry(field, s, iter);
+                if (ret == TRACE_TYPE_HANDLED && iter->cpu != cpu) {
+                        per_cpu_ptr(data->cpu_data, iter->cpu)->ignore = 1;
+                        ret = TRACE_TYPE_NO_CONSUME;
+                }
+                iter->cpu = cpu;
+                return ret;
+        }
 
         switch (entry->type) {
         case TRACE_GRAPH_ENT: {
@@ -952,7 +1026,7 @@ print_graph_function(struct trace_iterator *iter)
                  * sizeof(struct ftrace_graph_ent_entry) is very small,
                  * it can be safely saved at the stack.
                  */
-                struct ftrace_graph_ent_entry *field, saved;
+                struct ftrace_graph_ent_entry saved;
                 trace_assign_type(field, entry);
                 saved = *field;
                 return print_graph_entry(&saved, s, iter);
@@ -1030,31 +1104,54 @@ static void print_graph_headers(struct seq_file *s)
 static void graph_trace_open(struct trace_iterator *iter)
 {
         /* pid and depth on the last trace processed */
-        struct fgraph_data *data = alloc_percpu(struct fgraph_data);
+        struct fgraph_data *data;
         int cpu;
 
+        iter->private = NULL;
+
+        data = kzalloc(sizeof(*data), GFP_KERNEL);
         if (!data)
-                pr_warning("function graph tracer: not enough memory\n");
-        else
-                for_each_possible_cpu(cpu) {
-                        pid_t *pid = &(per_cpu_ptr(data, cpu)->last_pid);
-                        int *depth = &(per_cpu_ptr(data, cpu)->depth);
-                        *pid = -1;
-                        *depth = 0;
-                }
+                goto out_err;
+
+        data->cpu_data = alloc_percpu(struct fgraph_cpu_data);
+        if (!data->cpu_data)
+                goto out_err_free;
+
+        for_each_possible_cpu(cpu) {
+                pid_t *pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid);
+                int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
+                int *ignore = &(per_cpu_ptr(data->cpu_data, cpu)->ignore);
+                *pid = -1;
+                *depth = 0;
+                *ignore = 0;
+        }
 
         iter->private = data;
+
+        return;
+
+ out_err_free:
+        kfree(data);
+ out_err:
+        pr_warning("function graph tracer: not enough memory\n");
 }
 
 static void graph_trace_close(struct trace_iterator *iter)
 {
-        free_percpu(iter->private);
+        struct fgraph_data *data = iter->private;
+
+        if (data) {
+                free_percpu(data->cpu_data);
+                kfree(data);
+        }
 }
 
 static struct tracer graph_trace __read_mostly = {
         .name           = "function_graph",
         .open           = graph_trace_open,
+        .pipe_open      = graph_trace_open,
         .close          = graph_trace_close,
+        .pipe_close     = graph_trace_close,
         .wait_pipe      = poll_wait_pipe,
         .init           = graph_trace_init,
         .reset          = graph_trace_reset,
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index aff5f80b59b8..b52d397e57eb 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -606,23 +606,22 @@ static int create_trace_probe(int argc, char **argv)
          */
         struct trace_probe *tp;
         int i, ret = 0;
-        int is_return = 0;
+        int is_return = 0, is_delete = 0;
         char *symbol = NULL, *event = NULL, *arg = NULL, *group = NULL;
         unsigned long offset = 0;
         void *addr = NULL;
         char buf[MAX_EVENT_NAME_LEN];
 
-        if (argc < 2) {
-                pr_info("Probe point is not specified.\n");
-                return -EINVAL;
-        }
-
+        /* argc must be >= 1 */
         if (argv[0][0] == 'p')
                 is_return = 0;
         else if (argv[0][0] == 'r')
                 is_return = 1;
+        else if (argv[0][0] == '-')
+                is_delete = 1;
         else {
-                pr_info("Probe definition must be started with 'p' or 'r'.\n");
+                pr_info("Probe definition must be started with 'p', 'r' or"
+                        " '-'.\n");
                 return -EINVAL;
         }
 
@@ -642,7 +641,29 @@ static int create_trace_probe(int argc, char **argv)
                         return -EINVAL;
                 }
         }
+        if (!group)
+                group = KPROBE_EVENT_SYSTEM;
 
+        if (is_delete) {
+                if (!event) {
+                        pr_info("Delete command needs an event name.\n");
+                        return -EINVAL;
+                }
+                tp = find_probe_event(event, group);
+                if (!tp) {
+                        pr_info("Event %s/%s doesn't exist.\n", group, event);
+                        return -ENOENT;
+                }
+                /* delete an event */
+                unregister_trace_probe(tp);
+                free_trace_probe(tp);
+                return 0;
+        }
+
+        if (argc < 2) {
+                pr_info("Probe point is not specified.\n");
+                return -EINVAL;
+        }
         if (isdigit(argv[1][0])) {
                 if (is_return) {
                         pr_info("Return probe point must be a symbol.\n");
@@ -671,8 +692,6 @@ static int create_trace_probe(int argc, char **argv)
         argc -= 2; argv += 2;
 
         /* setup a probe */
-        if (!group)
-                group = KPROBE_EVENT_SYSTEM;
         if (!event) {
                 /* Make a new event name */
                 if (symbol)
@@ -1114,7 +1133,7 @@ static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
         struct trace_probe *tp = (struct trace_probe *)event_call->data;
 
         ret = trace_define_common_fields(event_call);
-        if (!ret)
+        if (ret)
                 return ret;
 
         DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
@@ -1132,7 +1151,7 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
         struct trace_probe *tp = (struct trace_probe *)event_call->data;
 
         ret = trace_define_common_fields(event_call);
-        if (!ret)
+        if (ret)
                 return ret;
 
         DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c
index ddfa0fd43bc0..acb87d4a4ac1 100644
--- a/kernel/trace/trace_ksym.c
+++ b/kernel/trace/trace_ksym.c
@@ -79,11 +79,12 @@ void ksym_collect_stats(unsigned long hbp_hit_addr)
 }
 #endif /* CONFIG_PROFILE_KSYM_TRACER */
 
-void ksym_hbp_handler(struct perf_event *hbp, void *data)
+void ksym_hbp_handler(struct perf_event *hbp, int nmi,
+                      struct perf_sample_data *data,
+                      struct pt_regs *regs)
 {
         struct ring_buffer_event *event;
         struct ksym_trace_entry *entry;
-        struct pt_regs *regs = data;
         struct ring_buffer *buffer;
         int pc;
 
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index b6c12c6a1bcd..8e46b3323cdc 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -23,13 +23,21 @@ static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
 
 static int next_event_type = __TRACE_LAST_TYPE + 1;
 
-void trace_print_seq(struct seq_file *m, struct trace_seq *s)
+int trace_print_seq(struct seq_file *m, struct trace_seq *s)
 {
         int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
+        int ret;
+
+        ret = seq_write(m, s->buffer, len);
 
-        seq_write(m, s->buffer, len);
+        /*
+         * Only reset this buffer if we successfully wrote to the
+         * seq_file buffer.
+         */
+        if (!ret)
+                trace_seq_init(s);
 
-        trace_seq_init(s);
+        return ret;
 }
 
 enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
@@ -85,7 +93,7 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
         va_list ap;
         int ret;
 
-        if (!len)
+        if (s->full || !len)
                 return 0;
 
         va_start(ap, fmt);
@@ -93,8 +101,10 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
         va_end(ap);
 
         /* If we can't write it all, don't bother writing anything */
-        if (ret >= len)
+        if (ret >= len) {
+                s->full = 1;
                 return 0;
+        }
 
         s->len += ret;
 
@@ -119,14 +129,16 @@ trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
         int len = (PAGE_SIZE - 1) - s->len;
         int ret;
 
-        if (!len)
+        if (s->full || !len)
                 return 0;
 
         ret = vsnprintf(s->buffer + s->len, len, fmt, args);
 
         /* If we can't write it all, don't bother writing anything */
-        if (ret >= len)
+        if (ret >= len) {
+                s->full = 1;
                 return 0;
+        }
 
         s->len += ret;
 
@@ -139,14 +151,16 @@ int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
         int len = (PAGE_SIZE - 1) - s->len;
         int ret;
 
-        if (!len)
+        if (s->full || !len)
                 return 0;
 
         ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
 
         /* If we can't write it all, don't bother writing anything */
-        if (ret >= len)
+        if (ret >= len) {
+                s->full = 1;
                 return 0;
+        }
 
         s->len += ret;
 
@@ -167,8 +181,13 @@ int trace_seq_puts(struct trace_seq *s, const char *str)
 {
         int len = strlen(str);
 
-        if (len > ((PAGE_SIZE - 1) - s->len))
+        if (s->full)
+                return 0;
+
+        if (len > ((PAGE_SIZE - 1) - s->len)) {
+                s->full = 1;
                 return 0;
+        }
 
         memcpy(s->buffer + s->len, str, len);
         s->len += len;
@@ -178,9 +197,14 @@ int trace_seq_puts(struct trace_seq *s, const char *str)
 
 int trace_seq_putc(struct trace_seq *s, unsigned char c)
 {
-        if (s->len >= (PAGE_SIZE - 1))
+        if (s->full)
                 return 0;
 
+        if (s->len >= (PAGE_SIZE - 1)) {
+                s->full = 1;
+                return 0;
+        }
+
         s->buffer[s->len++] = c;
 
         return 1;
@@ -188,9 +212,14 @@ int trace_seq_putc(struct trace_seq *s, unsigned char c)
 
 int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
 {
-        if (len > ((PAGE_SIZE - 1) - s->len))
+        if (s->full)
                 return 0;
 
+        if (len > ((PAGE_SIZE - 1) - s->len)) {
+                s->full = 1;
+                return 0;
+        }
+
         memcpy(s->buffer + s->len, mem, len);
         s->len += len;
 
@@ -203,6 +232,9 @@ int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
         const unsigned char *data = mem;
         int i, j;
 
+        if (s->full)
+                return 0;
+
 #ifdef __BIG_ENDIAN
         for (i = 0, j = 0; i < len; i++) {
 #else
@@ -220,8 +252,13 @@ void *trace_seq_reserve(struct trace_seq *s, size_t len)
 {
         void *ret;
 
-        if (len > ((PAGE_SIZE - 1) - s->len))
+        if (s->full)
+                return 0;
+
+        if (len > ((PAGE_SIZE - 1) - s->len)) {
+                s->full = 1;
                 return NULL;
+        }
 
         ret = s->buffer + s->len;
         s->len += len;
@@ -233,8 +270,14 @@ int trace_seq_path(struct trace_seq *s, struct path *path)
 {
         unsigned char *p;
 
-        if (s->len >= (PAGE_SIZE - 1))
+        if (s->full)
+                return 0;
+
+        if (s->len >= (PAGE_SIZE - 1)) {
+                s->full = 1;
                 return 0;
+        }
+
         p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
         if (!IS_ERR(p)) {
                 p = mangle_path(s->buffer + s->len, p, "\n");
@@ -247,6 +290,7 @@ int trace_seq_path(struct trace_seq *s, struct path *path)
                 return 1;
         }
 
+        s->full = 1;
         return 0;
 }
 
@@ -373,6 +417,9 @@ int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
         unsigned long vmstart = 0;
         int ret = 1;
 
+        if (s->full)
+                return 0;
+
         if (mm) {
                 const struct vm_area_struct *vma;
 
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 67e526b6ae81..dee48658805c 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -68,6 +68,116 @@ struct workqueue_struct {
 #endif
 };
 
+#ifdef CONFIG_DEBUG_OBJECTS_WORK
+
+static struct debug_obj_descr work_debug_descr;
+
+/*
+ * fixup_init is called when:
+ * - an active object is initialized
+ */
+static int work_fixup_init(void *addr, enum debug_obj_state state)
+{
+        struct work_struct *work = addr;
+
+        switch (state) {
+        case ODEBUG_STATE_ACTIVE:
+                cancel_work_sync(work);
+                debug_object_init(work, &work_debug_descr);
+                return 1;
+        default:
+                return 0;
+        }
+}
+
+/*
+ * fixup_activate is called when:
+ * - an active object is activated
+ * - an unknown object is activated (might be a statically initialized object)
+ */
+static int work_fixup_activate(void *addr, enum debug_obj_state state)
+{
+        struct work_struct *work = addr;
+
+        switch (state) {
+
+        case ODEBUG_STATE_NOTAVAILABLE:
+                /*
+                 * This is not really a fixup. The work struct was
+                 * statically initialized. We just make sure that it
+                 * is tracked in the object tracker.
+                 */
+                if (test_bit(WORK_STRUCT_STATIC, work_data_bits(work))) {
+                        debug_object_init(work, &work_debug_descr);
+                        debug_object_activate(work, &work_debug_descr);
+                        return 0;
+                }
+                WARN_ON_ONCE(1);
+                return 0;
+
+        case ODEBUG_STATE_ACTIVE:
+                WARN_ON(1);
+
+        default:
+                return 0;
+        }
+}
+
+/*
+ * fixup_free is called when:
+ * - an active object is freed
+ */
+static int work_fixup_free(void *addr, enum debug_obj_state state)
+{
+        struct work_struct *work = addr;
+
+        switch (state) {
+        case ODEBUG_STATE_ACTIVE:
+                cancel_work_sync(work);
+                debug_object_free(work, &work_debug_descr);
+                return 1;
+        default:
+                return 0;
+        }
+}
+
+static struct debug_obj_descr work_debug_descr = {
+        .name           = "work_struct",
+        .fixup_init     = work_fixup_init,
+        .fixup_activate = work_fixup_activate,
+        .fixup_free     = work_fixup_free,
+};
+
+static inline void debug_work_activate(struct work_struct *work)
+{
+        debug_object_activate(work, &work_debug_descr);
+}
+
+static inline void debug_work_deactivate(struct work_struct *work)
+{
+        debug_object_deactivate(work, &work_debug_descr);
+}
+
+void __init_work(struct work_struct *work, int onstack)
+{
+        if (onstack)
+                debug_object_init_on_stack(work, &work_debug_descr);
+        else
+                debug_object_init(work, &work_debug_descr);
+}
+EXPORT_SYMBOL_GPL(__init_work);
+
+void destroy_work_on_stack(struct work_struct *work)
+{
+        debug_object_free(work, &work_debug_descr);
+}
+EXPORT_SYMBOL_GPL(destroy_work_on_stack);
+
+#else
+static inline void debug_work_activate(struct work_struct *work) { }
+static inline void debug_work_deactivate(struct work_struct *work) { }
+#endif
+
 /* Serializes the accesses to the list of workqueues. */
 static DEFINE_SPINLOCK(workqueue_lock);
 static LIST_HEAD(workqueues);
@@ -145,6 +255,7 @@ static void __queue_work(struct cpu_workqueue_struct *cwq,
 {
         unsigned long flags;
 
+        debug_work_activate(work);
         spin_lock_irqsave(&cwq->lock, flags);
         insert_work(cwq, work, &cwq->worklist);
         spin_unlock_irqrestore(&cwq->lock, flags);
@@ -280,6 +391,7 @@ static void run_workqueue(struct cpu_workqueue_struct *cwq)
                 struct lockdep_map lockdep_map = work->lockdep_map;
 #endif
                 trace_workqueue_execution(cwq->thread, work);
+                debug_work_deactivate(work);
                 cwq->current_work = work;
                 list_del_init(cwq->worklist.next);
                 spin_unlock_irq(&cwq->lock);
@@ -350,11 +462,18 @@ static void wq_barrier_func(struct work_struct *work)
 static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
                         struct wq_barrier *barr, struct list_head *head)
 {
-        INIT_WORK(&barr->work, wq_barrier_func);
+        /*
+         * debugobject calls are safe here even with cwq->lock locked
+         * as we know for sure that this will not trigger any of the
+         * checks and call back into the fixup functions where we
+         * might deadlock.
+         */
+        INIT_WORK_ON_STACK(&barr->work, wq_barrier_func);
         __set_bit(WORK_STRUCT_PENDING, work_data_bits(&barr->work));
 
         init_completion(&barr->done);
 
+        debug_work_activate(&barr->work);
         insert_work(cwq, &barr->work, head);
 }
 
@@ -372,8 +491,10 @@ static int flush_cpu_workqueue(struct cpu_workqueue_struct *cwq)
         }
         spin_unlock_irq(&cwq->lock);
 
-        if (active)
+        if (active) {
                 wait_for_completion(&barr.done);
+                destroy_work_on_stack(&barr.work);
+        }
 
         return active;
 }
@@ -451,6 +572,7 @@ out:
                 return 0;
 
         wait_for_completion(&barr.done);
+        destroy_work_on_stack(&barr.work);
         return 1;
 }
 EXPORT_SYMBOL_GPL(flush_work);
@@ -485,6 +607,7 @@ static int try_to_grab_pending(struct work_struct *work)
                  */
                 smp_rmb();
                 if (cwq == get_wq_data(work)) {
+                        debug_work_deactivate(work);
                         list_del_init(&work->entry);
                         ret = 1;
                 }
@@ -507,8 +630,10 @@ static void wait_on_cpu_work(struct cpu_workqueue_struct *cwq,
         }
         spin_unlock_irq(&cwq->lock);
 
-        if (unlikely(running))
+        if (unlikely(running)) {
                 wait_for_completion(&barr.done);
+                destroy_work_on_stack(&barr.work);
+        }
 }
 
 static void wait_on_work(struct work_struct *work)