16 files changed, 223 insertions, 87 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 32b48c88971..1b5c081d8b9 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -2300,7 +2300,10 @@ do {					\
         return div64_u64(dividend, divisor);
 }
 
-static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count)
+static DEFINE_PER_CPU(int, perf_throttled_count);
+static DEFINE_PER_CPU(u64, perf_throttled_seq);
+
+static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable)
 {
         struct hw_perf_event *hwc = &event->hw;
         s64 period, sample_period;
@@ -2319,22 +2322,40 @@ static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count)
         hwc->sample_period = sample_period;
 
         if (local64_read(&hwc->period_left) > 8*sample_period) {
-                event->pmu->stop(event, PERF_EF_UPDATE);
+                if (disable)
+                        event->pmu->stop(event, PERF_EF_UPDATE);
+
                 local64_set(&hwc->period_left, 0);
-                event->pmu->start(event, PERF_EF_RELOAD);
+
+                if (disable)
+                        event->pmu->start(event, PERF_EF_RELOAD);
         }
 }
 
-static void perf_ctx_adjust_freq(struct perf_event_context *ctx, u64 period)
+/*
+ * combine freq adjustment with unthrottling to avoid two passes over the
+ * events. At the same time, make sure, having freq events does not change
+ * the rate of unthrottling as that would introduce bias.
+ */
+static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx,
+                                           int needs_unthr)
 {
         struct perf_event *event;
         struct hw_perf_event *hwc;
-        u64 interrupts, now;
+        u64 now, period = TICK_NSEC;
         s64 delta;
 
-        if (!ctx->nr_freq)
+        /*
+         * only need to iterate over all events iff:
+         * - context have events in frequency mode (needs freq adjust)
+         * - there are events to unthrottle on this cpu
+         */
+        if (!(ctx->nr_freq || needs_unthr))
                 return;
 
+        raw_spin_lock(&ctx->lock);
+        perf_pmu_disable(ctx->pmu);
+
         list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
                 if (event->state != PERF_EVENT_STATE_ACTIVE)
                         continue;
@@ -2344,13 +2365,8 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx, u64 period)
 
                 hwc = &event->hw;
 
-                interrupts = hwc->interrupts;
-                hwc->interrupts = 0;
-
-                /*
-                 * unthrottle events on the tick
-                 */
-                if (interrupts == MAX_INTERRUPTS) {
+                if (needs_unthr && hwc->interrupts == MAX_INTERRUPTS) {
+                        hwc->interrupts = 0;
                         perf_log_throttle(event, 1);
                         event->pmu->start(event, 0);
                 }
@@ -2358,14 +2374,30 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx, u64 period)
                 if (!event->attr.freq || !event->attr.sample_freq)
                         continue;
 
-                event->pmu->read(event);
+                /*
+                 * stop the event and update event->count
+                 */
+                event->pmu->stop(event, PERF_EF_UPDATE);
+
                 now = local64_read(&event->count);
                 delta = now - hwc->freq_count_stamp;
                 hwc->freq_count_stamp = now;
 
+                /*
+                 * restart the event
+                 * reload only if value has changed
+                 * we have stopped the event so tell that
+                 * to perf_adjust_period() to avoid stopping it
+                 * twice.
+                 */
                 if (delta > 0)
-                        perf_adjust_period(event, period, delta);
+                        perf_adjust_period(event, period, delta, false);
+
+                event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0);
         }
+
+        perf_pmu_enable(ctx->pmu);
+        raw_spin_unlock(&ctx->lock);
 }
 
 /*
@@ -2388,16 +2420,13 @@ static void rotate_ctx(struct perf_event_context *ctx)
  */
 static void perf_rotate_context(struct perf_cpu_context *cpuctx)
 {
-        u64 interval = (u64)cpuctx->jiffies_interval * TICK_NSEC;
         struct perf_event_context *ctx = NULL;
-        int rotate = 0, remove = 1, freq = 0;
+        int rotate = 0, remove = 1;
 
         if (cpuctx->ctx.nr_events) {
                 remove = 0;
                 if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active)
                         rotate = 1;
-                if (cpuctx->ctx.nr_freq)
-                        freq = 1;
         }
 
         ctx = cpuctx->task_ctx;
@@ -2405,37 +2434,26 @@ static void perf_rotate_context(struct perf_cpu_context *cpuctx)
                 remove = 0;
                 if (ctx->nr_events != ctx->nr_active)
                         rotate = 1;
-                if (ctx->nr_freq)
-                        freq = 1;
         }
 
-        if (!rotate && !freq)
+        if (!rotate)
                 goto done;
 
         perf_ctx_lock(cpuctx, cpuctx->task_ctx);
         perf_pmu_disable(cpuctx->ctx.pmu);
 
-        if (freq) {
-                perf_ctx_adjust_freq(&cpuctx->ctx, interval);
-                if (ctx)
-                        perf_ctx_adjust_freq(ctx, interval);
-        }
-
-        if (rotate) {
-                cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
-                if (ctx)
-                        ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE);
+        cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
+        if (ctx)
+                ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE);
 
-                rotate_ctx(&cpuctx->ctx);
-                if (ctx)
-                        rotate_ctx(ctx);
+        rotate_ctx(&cpuctx->ctx);
+        if (ctx)
+                rotate_ctx(ctx);
 
-                perf_event_sched_in(cpuctx, ctx, current);
-        }
+        perf_event_sched_in(cpuctx, ctx, current);
 
         perf_pmu_enable(cpuctx->ctx.pmu);
         perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
-
 done:
         if (remove)
                 list_del_init(&cpuctx->rotation_list);
@@ -2445,10 +2463,22 @@ void perf_event_task_tick(void)
 {
         struct list_head *head = &__get_cpu_var(rotation_list);
         struct perf_cpu_context *cpuctx, *tmp;
+        struct perf_event_context *ctx;
+        int throttled;
 
         WARN_ON(!irqs_disabled());
 
+        __this_cpu_inc(perf_throttled_seq);
+        throttled = __this_cpu_xchg(perf_throttled_count, 0);
+
         list_for_each_entry_safe(cpuctx, tmp, head, rotation_list) {
+                ctx = &cpuctx->ctx;
+                perf_adjust_freq_unthr_context(ctx, throttled);
+
+                ctx = cpuctx->task_ctx;
+                if (ctx)
+                        perf_adjust_freq_unthr_context(ctx, throttled);
+
                 if (cpuctx->jiffies_interval == 1 ||
                                 !(jiffies % cpuctx->jiffies_interval))
                         perf_rotate_context(cpuctx);
@@ -4509,6 +4539,7 @@ static int __perf_event_overflow(struct perf_event *event,
 {
         int events = atomic_read(&event->event_limit);
         struct hw_perf_event *hwc = &event->hw;
+        u64 seq;
         int ret = 0;
 
         /*
@@ -4518,14 +4549,20 @@ static int __perf_event_overflow(struct perf_event *event,
         if (unlikely(!is_sampling_event(event)))
                 return 0;
 
-        if (unlikely(hwc->interrupts >= max_samples_per_tick)) {
-                if (throttle) {
+        seq = __this_cpu_read(perf_throttled_seq);
+        if (seq != hwc->interrupts_seq) {
+                hwc->interrupts_seq = seq;
+                hwc->interrupts = 1;
+        } else {
+                hwc->interrupts++;
+                if (unlikely(throttle
+                             && hwc->interrupts >= max_samples_per_tick)) {
+                        __this_cpu_inc(perf_throttled_count);
                         hwc->interrupts = MAX_INTERRUPTS;
                         perf_log_throttle(event, 0);
                         ret = 1;
                 }
-        } else
-                hwc->interrupts++;
+        }
 
         if (event->attr.freq) {
                 u64 now = perf_clock();
@@ -4534,7 +4571,7 @@ static int __perf_event_overflow(struct perf_event *event,
                 hwc->freq_time_stamp = now;
 
                 if (delta > 0 && delta < 2*TICK_NSEC)
-                        perf_adjust_period(event, delta, hwc->last_period);
+                        perf_adjust_period(event, delta, hwc->last_period, true);
         }
 
         /*
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index b7971d6f38b..ee706ce44aa 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -651,10 +651,10 @@ int __init init_hw_breakpoint(void)
 
  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));
+                if (err_cpu == cpu)
+                        break;
         }
 
         return -ENOMEM;
diff --git a/kernel/exit.c b/kernel/exit.c
index fd0af05e063..8e6b0e626b9 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1038,6 +1038,22 @@ void do_exit(long code)
         if (tsk->nr_dirtied)
                 __this_cpu_add(dirty_throttle_leaks, tsk->nr_dirtied);
         exit_rcu();
+
+        /*
+         * The setting of TASK_RUNNING by try_to_wake_up() may be delayed
+         * when the following two conditions become true.
+         *   - There is race condition of mmap_sem (It is acquired by
+         *     exit_mm()), and
+         *   - SMI occurs before setting TASK_RUNINNG.
+         *     (or hypervisor of virtual machine switches to other guest)
+         *  As a result, we may become TASK_RUNNING after becoming TASK_DEAD
+         *
+         * To avoid it, we have to wait for releasing tsk->pi_lock which
+         * is held by try_to_wake_up()
+         */
+        smp_mb();
+        raw_spin_unlock_wait(&tsk->pi_lock);
+
         /* causes final put_task_struct in finish_task_switch(). */
         tsk->state = TASK_DEAD;
         tsk->flags |= PF_NOFREEZE;      /* tell freezer to ignore us */
diff --git a/kernel/fork.c b/kernel/fork.c
index 051f090d40c..e2cd3e2a5ae 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -66,6 +66,7 @@
 #include <linux/user-return-notifier.h>
 #include <linux/oom.h>
 #include <linux/khugepaged.h>
+#include <linux/signalfd.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -647,6 +648,26 @@ struct mm_struct *get_task_mm(struct task_struct *task)
 }
 EXPORT_SYMBOL_GPL(get_task_mm);
 
+struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
+{
+        struct mm_struct *mm;
+        int err;
+
+        err =  mutex_lock_killable(&task->signal->cred_guard_mutex);
+        if (err)
+                return ERR_PTR(err);
+
+        mm = get_task_mm(task);
+        if (mm && mm != current->mm &&
+                        !ptrace_may_access(task, mode)) {
+                mmput(mm);
+                mm = ERR_PTR(-EACCES);
+        }
+        mutex_unlock(&task->signal->cred_guard_mutex);
+
+        return mm;
+}
+
 /* Please note the differences between mmput and mm_release.
  * mmput is called whenever we stop holding onto a mm_struct,
  * error success whatever.
@@ -890,7 +911,7 @@ static int copy_io(unsigned long clone_flags, struct task_struct *tsk)
                         return -ENOMEM;
 
                 new_ioc->ioprio = ioc->ioprio;
-                put_io_context(new_ioc, NULL);
+                put_io_context(new_ioc);
         }
 #endif
         return 0;
@@ -915,8 +936,10 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
 
 void __cleanup_sighand(struct sighand_struct *sighand)
 {
-        if (atomic_dec_and_test(&sighand->count))
+        if (atomic_dec_and_test(&sighand->count)) {
+                signalfd_cleanup(sighand);
                 kmem_cache_free(sighand_cachep, sighand);
+        }
 }
 
 
diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c
index 342d8f44e40..0119b9d467a 100644
--- a/kernel/irq/autoprobe.c
+++ b/kernel/irq/autoprobe.c
@@ -53,7 +53,7 @@ unsigned long probe_irq_on(void)
                         if (desc->irq_data.chip->irq_set_type)
                                 desc->irq_data.chip->irq_set_type(&desc->irq_data,
                                                          IRQ_TYPE_PROBE);
-                        irq_startup(desc);
+                        irq_startup(desc, false);
                 }
                 raw_spin_unlock_irq(&desc->lock);
         }
@@ -70,7 +70,7 @@ unsigned long probe_irq_on(void)
                 raw_spin_lock_irq(&desc->lock);
                 if (!desc->action && irq_settings_can_probe(desc)) {
                         desc->istate |= IRQS_AUTODETECT | IRQS_WAITING;
-                        if (irq_startup(desc))
+                        if (irq_startup(desc, false))
                                 desc->istate |= IRQS_PENDING;
                 }
                 raw_spin_unlock_irq(&desc->lock);
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index f7c543a801d..fb7db75ee0c 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -157,19 +157,22 @@ static void irq_state_set_masked(struct irq_desc *desc)
         irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
 }
 
-int irq_startup(struct irq_desc *desc)
+int irq_startup(struct irq_desc *desc, bool resend)
 {
+        int ret = 0;
+
         irq_state_clr_disabled(desc);
         desc->depth = 0;
 
         if (desc->irq_data.chip->irq_startup) {
-                int ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
+                ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
                 irq_state_clr_masked(desc);
-                return ret;
+        } else {
+                irq_enable(desc);
         }
-
-        irq_enable(desc);
-        return 0;
+        if (resend)
+                check_irq_resend(desc, desc->irq_data.irq);
+        return ret;
 }
 
 void irq_shutdown(struct irq_desc *desc)
@@ -330,6 +333,24 @@ out_unlock:
 }
 EXPORT_SYMBOL_GPL(handle_simple_irq);
 
+/*
+ * Called unconditionally from handle_level_irq() and only for oneshot
+ * interrupts from handle_fasteoi_irq()
+ */
+static void cond_unmask_irq(struct irq_desc *desc)
+{
+        /*
+         * We need to unmask in the following cases:
+         * - Standard level irq (IRQF_ONESHOT is not set)
+         * - Oneshot irq which did not wake the thread (caused by a
+         *   spurious interrupt or a primary handler handling it
+         *   completely).
+         */
+        if (!irqd_irq_disabled(&desc->irq_data) &&
+            irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
+                unmask_irq(desc);
+}
+
 /**
  *      handle_level_irq - Level type irq handler
  *      @irq:   the interrupt number
@@ -362,8 +383,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
 
         handle_irq_event(desc);
 
-        if (!irqd_irq_disabled(&desc->irq_data) && !(desc->istate & IRQS_ONESHOT))
-                unmask_irq(desc);
+        cond_unmask_irq(desc);
+
 out_unlock:
         raw_spin_unlock(&desc->lock);
 }
@@ -417,6 +438,9 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
         preflow_handler(desc);
         handle_irq_event(desc);
 
+        if (desc->istate & IRQS_ONESHOT)
+                cond_unmask_irq(desc);
+
 out_eoi:
         desc->irq_data.chip->irq_eoi(&desc->irq_data);
 out_unlock:
@@ -625,7 +649,7 @@ __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
                 irq_settings_set_noprobe(desc);
                 irq_settings_set_norequest(desc);
                 irq_settings_set_nothread(desc);
-                irq_startup(desc);
+                irq_startup(desc, true);
         }
 out:
         irq_put_desc_busunlock(desc, flags);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index b7952316016..40378ff877e 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -67,7 +67,7 @@ extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
 extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp);
 extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume);
 
-extern int irq_startup(struct irq_desc *desc);
+extern int irq_startup(struct irq_desc *desc, bool resend);
 extern void irq_shutdown(struct irq_desc *desc);
 extern void irq_enable(struct irq_desc *desc);
 extern void irq_disable(struct irq_desc *desc);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index a9a9dbe49fe..32313c08444 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1027,7 +1027,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                         desc->istate |= IRQS_ONESHOT;
 
                 if (irq_settings_can_autoenable(desc))
-                        irq_startup(desc);
+                        irq_startup(desc, true);
                 else
                         /* Undo nested disables: */
                         desc->depth = 1;
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 29f5b65bee2..9788c0ec6f4 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1673,8 +1673,12 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p,
                 ri->rp = rp;
                 ri->task = current;
 
-                if (rp->entry_handler && rp->entry_handler(ri, regs))
+                if (rp->entry_handler && rp->entry_handler(ri, regs)) {
+                        raw_spin_lock_irqsave(&rp->lock, flags);
+                        hlist_add_head(&ri->hlist, &rp->free_instances);
+                        raw_spin_unlock_irqrestore(&rp->lock, flags);
                         return 0;
+                }
 
                 arch_prepare_kretprobe(ri, regs);
 
diff --git a/kernel/params.c b/kernel/params.c
index 32ee0430828..4bc965d8a1f 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -97,7 +97,8 @@ static int parse_one(char *param,
         for (i = 0; i < num_params; i++) {
                 if (parameq(param, params[i].name)) {
                         /* No one handled NULL, so do it here. */
-                        if (!val && params[i].ops->set != param_set_bool)
+                        if (!val && params[i].ops->set != param_set_bool
+                            && params[i].ops->set != param_set_bint)
                                 return -EINVAL;
                         pr_debug("They are equal!  Calling %p\n",
                                params[i].ops->set);
diff --git a/kernel/pid.c b/kernel/pid.c
index ce8e00deacc..9f08dfabaf1 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -543,12 +543,12 @@ struct pid *find_ge_pid(int nr, struct pid_namespace *ns)
  */
 void __init pidhash_init(void)
 {
-        int i, pidhash_size;
+        unsigned int i, pidhash_size;
 
         pid_hash = alloc_large_system_hash("PID", sizeof(*pid_hash), 0, 18,
                                            HASH_EARLY | HASH_SMALL,
                                            &pidhash_shift, NULL, 4096);
-        pidhash_size = 1 << pidhash_shift;
+        pidhash_size = 1U << pidhash_shift;
 
         for (i = 0; i < pidhash_size; i++)
                 INIT_HLIST_HEAD(&pid_hash[i]);
diff --git a/kernel/relay.c b/kernel/relay.c
index 4335e1d7ee2..ab56a1764d4 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -164,10 +164,14 @@ depopulate:
  */
 static struct rchan_buf *relay_create_buf(struct rchan *chan)
 {
-        struct rchan_buf *buf = kzalloc(sizeof(struct rchan_buf), GFP_KERNEL);
-        if (!buf)
+        struct rchan_buf *buf;
+
+        if (chan->n_subbufs > UINT_MAX / sizeof(size_t *))
                 return NULL;
 
+        buf = kzalloc(sizeof(struct rchan_buf), GFP_KERNEL);
+        if (!buf)
+                return NULL;
         buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL);
         if (!buf->padding)
                 goto free_buf;
@@ -574,6 +578,8 @@ struct rchan *relay_open(const char *base_filename,
 
         if (!(subbuf_size && n_subbufs))
                 return NULL;
+        if (subbuf_size > UINT_MAX / n_subbufs)
+                return NULL;
 
         chan = kzalloc(sizeof(struct rchan), GFP_KERNEL);
         if (!chan)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index df00cb09263..33a0676ea74 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -74,6 +74,7 @@
 
 #include <asm/tlb.h>
 #include <asm/irq_regs.h>
+#include <asm/mutex.h>
 #ifdef CONFIG_PARAVIRT
 #include <asm/paravirt.h>
 #endif
@@ -723,9 +724,6 @@ static void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
         p->sched_class->dequeue_task(rq, p, flags);
 }
 
-/*
- * activate_task - move a task to the runqueue.
- */
 void activate_task(struct rq *rq, struct task_struct *p, int flags)
 {
         if (task_contributes_to_load(p))
@@ -734,9 +732,6 @@ void activate_task(struct rq *rq, struct task_struct *p, int flags)
         enqueue_task(rq, p, flags);
 }
 
-/*
- * deactivate_task - remove a task from the runqueue.
- */
 void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
 {
         if (task_contributes_to_load(p))
@@ -1937,7 +1932,6 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
         local_irq_enable();
 #endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
         finish_lock_switch(rq, prev);
-        trace_sched_stat_sleeptime(current, rq->clock);
 
         fire_sched_in_preempt_notifiers(current);
         if (mm)
@@ -4134,7 +4128,7 @@ recheck:
         on_rq = p->on_rq;
         running = task_current(rq, p);
         if (on_rq)
-                deactivate_task(rq, p, 0);
+                dequeue_task(rq, p, 0);
         if (running)
                 p->sched_class->put_prev_task(rq, p);
 
@@ -4147,7 +4141,7 @@ recheck:
         if (running)
                 p->sched_class->set_curr_task(rq);
         if (on_rq)
-                activate_task(rq, p, 0);
+                enqueue_task(rq, p, 0);
 
         check_class_changed(rq, p, prev_class, oldprio);
         task_rq_unlock(rq, p, &flags);
@@ -4998,9 +4992,9 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
          * placed properly.
          */
         if (p->on_rq) {
-                deactivate_task(rq_src, p, 0);
+                dequeue_task(rq_src, p, 0);
                 set_task_cpu(p, dest_cpu);
-                activate_task(rq_dest, p, 0);
+                enqueue_task(rq_dest, p, 0);
                 check_preempt_curr(rq_dest, p, 0);
         }
 done:
@@ -6734,7 +6728,7 @@ int __init sched_create_sysfs_power_savings_entries(struct device *dev)
 static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
                              void *hcpu)
 {
-        switch (action & ~CPU_TASKS_FROZEN) {
+        switch (action) {
         case CPU_ONLINE:
         case CPU_DOWN_FAILED:
                 cpuset_update_active_cpus();
@@ -6747,7 +6741,7 @@ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
 static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action,
                                void *hcpu)
 {
-        switch (action & ~CPU_TASKS_FROZEN) {
+        switch (action) {
         case CPU_DOWN_PREPARE:
                 cpuset_update_active_cpus();
                 return NOTIFY_OK;
@@ -7032,10 +7026,10 @@ static void normalize_task(struct rq *rq, struct task_struct *p)
 
         on_rq = p->on_rq;
         if (on_rq)
-                deactivate_task(rq, p, 0);
+                dequeue_task(rq, p, 0);
         __setscheduler(rq, p, SCHED_NORMAL, 0);
         if (on_rq) {
-                activate_task(rq, p, 0);
+                enqueue_task(rq, p, 0);
                 resched_task(rq->curr);
         }
 
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 84adb2d66cb..aca16b843b7 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1003,6 +1003,7 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
                 if (unlikely(delta > se->statistics.sleep_max))
                         se->statistics.sleep_max = delta;
 
+                se->statistics.sleep_start = 0;
                 se->statistics.sum_sleep_runtime += delta;
 
                 if (tsk) {
@@ -1019,6 +1020,7 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
                 if (unlikely(delta > se->statistics.block_max))
                         se->statistics.block_max = delta;
 
+                se->statistics.block_start = 0;
                 se->statistics.sum_sleep_runtime += delta;
 
                 if (tsk) {
@@ -4866,6 +4868,15 @@ static void nohz_balancer_kick(int cpu)
         return;
 }
 
+static inline void clear_nohz_tick_stopped(int cpu)
+{
+        if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
+                cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
+                atomic_dec(&nohz.nr_cpus);
+                clear_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
+        }
+}
+
 static inline void set_cpu_sd_state_busy(void)
 {
         struct sched_domain *sd;
@@ -4904,6 +4915,12 @@ void select_nohz_load_balancer(int stop_tick)
 {
         int cpu = smp_processor_id();
 
+        /*
+         * If this cpu is going down, then nothing needs to be done.
+         */
+        if (!cpu_active(cpu))
+                return;
+
         if (stop_tick) {
                 if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))
                         return;
@@ -4914,6 +4931,18 @@ void select_nohz_load_balancer(int stop_tick)
         }
         return;
 }
+
+static int __cpuinit sched_ilb_notifier(struct notifier_block *nfb,
+                                        unsigned long action, void *hcpu)
+{
+        switch (action & ~CPU_TASKS_FROZEN) {
+        case CPU_DYING:
+                clear_nohz_tick_stopped(smp_processor_id());
+                return NOTIFY_OK;
+        default:
+                return NOTIFY_DONE;
+        }
+}
 #endif
 
 static DEFINE_SPINLOCK(balancing);
@@ -5070,11 +5099,7 @@ static inline int nohz_kick_needed(struct rq *rq, int cpu)
         * busy tick after returning from idle, we will update the busy stats.
         */
         set_cpu_sd_state_busy();
-        if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
-                clear_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
-                cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
-                atomic_dec(&nohz.nr_cpus);
-        }
+        clear_nohz_tick_stopped(cpu);
 
         /*
          * None are in tickless mode and hence no need for NOHZ idle load
@@ -5590,6 +5615,7 @@ __init void init_sched_fair_class(void)
 
 #ifdef CONFIG_NO_HZ
         zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
+        cpu_notifier(sched_ilb_notifier, 0);
 #endif
 #endif /* SMP */
 
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 3640ebbb466..f42ae7fb5ec 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1587,6 +1587,11 @@ static int push_rt_task(struct rq *rq)
         if (!next_task)
                 return 0;
 
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+       if (unlikely(task_running(rq, next_task)))
+               return 0;
+#endif
+
 retry:
         if (unlikely(next_task == rq->curr)) {
                 WARN_ON(1);
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 1d7bca7f4f5..d117262deba 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -296,7 +296,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
                 if (__this_cpu_read(soft_watchdog_warn) == true)
                         return HRTIMER_RESTART;
 
-                printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
+                printk(KERN_EMERG "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
                         smp_processor_id(), duration,
                         current->comm, task_pid_nr(current));
                 print_modules();