Merge remote-tracking branch 'korg/linux-3.0.y' into cm-13.0

Conflicts:
	crypto/algapi.c
	drivers/gpu/drm/i915/i915_debugfs.c
	drivers/gpu/drm/i915/intel_display.c
	drivers/video/fbmem.c
	include/linux/nls.h
	kernel/cgroup.c
	kernel/signal.c
	kernel/timeconst.pl
	net/ipv4/ping.c

Change-Id: I1f532925d1743df74d66bcdd6fc92f05c72ee0dd

35 files changed, 586 insertions, 228 deletions

diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index f6b4ac7..7d9731d 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -614,9 +614,9 @@ void audit_trim_trees(void)
 		}
 		spin_unlock(&hash_lock);
 		trim_marked(tree);
-		put_tree(tree);
 		drop_collected_mounts(root_mnt);
 skip_it:
+		put_tree(tree);
 		mutex_lock(&audit_filter_mutex);
 	}
 	list_del(&cursor);
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 3948f0a..e4f8595 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -366,10 +366,19 @@ static void free_css_set_work(struct work_struct *work)
 		struct cgroup *cgrp = link->cgrp;
 		list_del(&link->cg_link_list);
 		list_del(&link->cgrp_link_list);
+
+                /*
+                 * We may not be holding cgroup_mutex, and if cgrp->count is
+                 * dropped to 0 the cgroup can be destroyed at any time, hence
+                 * rcu_read_lock is used to keep it alive.
+                 */
+                rcu_read_lock();
 		if (atomic_dec_and_test(&cgrp->count)) {
 			check_for_release(cgrp);
 			cgroup_wakeup_rmdir_waiter(cgrp);
 		}
+                rcu_read_unlock();
+
 		kfree(link);
 	}
 	write_unlock(&css_set_lock);
@@ -2028,7 +2037,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
 	if (!group)
 		return -ENOMEM;
 	/* pre-allocate to guarantee space while iterating in rcu read-side. */
-	retval = flex_array_prealloc(group, 0, group_size - 1, GFP_KERNEL);
+	retval = flex_array_prealloc(group, 0, group_size, GFP_KERNEL);
 	if (retval)
 		goto out_free_group_list;
 
@@ -3525,6 +3534,7 @@ static int cgroup_write_event_control(struct cgroup *cgrp, struct cftype *cft,
 				      const char *buffer)
 {
 	struct cgroup_event *event = NULL;
+	struct cgroup *cgrp_cfile;
 	unsigned int efd, cfd;
 	struct file *efile = NULL;
 	struct file *cfile = NULL;
@@ -3579,6 +3589,16 @@ static int cgroup_write_event_control(struct cgroup *cgrp, struct cftype *cft,
 		goto fail;
 	}
 
+	/*
+	 * The file to be monitored must be in the same cgroup as
+	 * cgroup.event_control is.
+	 */
+	cgrp_cfile = __d_cgrp(cfile->f_dentry->d_parent);
+	if (cgrp_cfile != cgrp) {
+		ret = -EINVAL;
+		goto fail;
+	}
+
 	if (!event->cft->register_event || !event->cft->unregister_event) {
 		ret = -EINVAL;
 		goto fail;
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 6cbe033..ea76c9c 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -2499,8 +2499,16 @@ void cpuset_print_task_mems_allowed(struct task_struct *tsk)
 
 	dentry = task_cs(tsk)->css.cgroup->dentry;
 	spin_lock(&cpuset_buffer_lock);
-	snprintf(cpuset_name, CPUSET_NAME_LEN,
-		 dentry ? (const char *)dentry->d_name.name : "/");
+
+	if (!dentry) {
+		strcpy(cpuset_name, "/");
+	} else {
+		spin_lock(&dentry->d_lock);
+		strlcpy(cpuset_name, (const char *)dentry->d_name.name,
+			CPUSET_NAME_LEN);
+		spin_unlock(&dentry->d_lock);
+	}
+
 	nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN,
 			   tsk->mems_allowed);
 	printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n",
diff --git a/kernel/events/core.c b/kernel/events/core.c
index b582650..acdc087 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -223,9 +223,9 @@ perf_cgroup_match(struct perf_event *event)
 	return !event->cgrp || event->cgrp == cpuctx->cgrp;
 }
 
-static inline void perf_get_cgroup(struct perf_event *event)
+static inline bool perf_tryget_cgroup(struct perf_event *event)
 {
-	css_get(&event->cgrp->css);
+	return css_tryget(&event->cgrp->css);
 }
 
 static inline void perf_put_cgroup(struct perf_event *event)
@@ -342,6 +342,8 @@ void perf_cgroup_switch(struct task_struct *task, int mode)
 	list_for_each_entry_rcu(pmu, &pmus, entry) {
 
 		cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
+		if (cpuctx->unique_pmu != pmu)
+			continue; /* ensure we process each cpuctx once */
 
 		perf_pmu_disable(cpuctx->ctx.pmu);
 
@@ -365,9 +367,10 @@ void perf_cgroup_switch(struct task_struct *task, int mode)
 
 			if (mode & PERF_CGROUP_SWIN) {
 				WARN_ON_ONCE(cpuctx->cgrp);
-				/* set cgrp before ctxsw in to
-				 * allow event_filter_match() to not
-				 * have to pass task around
+				/*
+				 * set cgrp before ctxsw in to allow
+				 * event_filter_match() to not have to pass
+				 * task around
 				 */
 				cpuctx->cgrp = perf_cgroup_from_task(task);
 				cpu_ctx_sched_in(cpuctx, EVENT_ALL, task);
@@ -415,7 +418,11 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 	event->cgrp = cgrp;
 
 	/* must be done before we fput() the file */
-	perf_get_cgroup(event);
+	if (!perf_tryget_cgroup(event)) {
+		event->cgrp = NULL;
+		ret = -ENOENT;
+		goto out;
+	}
 
 	/*
 	 * all events in a group must monitor
@@ -651,8 +658,18 @@ perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags)
 {
 	struct perf_event_context *ctx;
 
-	rcu_read_lock();
 retry:
+	/*
+	 * One of the few rules of preemptible RCU is that one cannot do
+	 * rcu_read_unlock() while holding a scheduler (or nested) lock when
+	 * part of the read side critical section was preemptible -- see
+	 * rcu_read_unlock_special().
+	 *
+	 * Since ctx->lock nests under rq->lock we must ensure the entire read
+	 * side critical section is non-preemptible.
+	 */
+	preempt_disable();
+	rcu_read_lock();
 	ctx = rcu_dereference(task->perf_event_ctxp[ctxn]);
 	if (ctx) {
 		/*
@@ -668,6 +685,8 @@ retry:
 		raw_spin_lock_irqsave(&ctx->lock, *flags);
 		if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) {
 			raw_spin_unlock_irqrestore(&ctx->lock, *flags);
+			rcu_read_unlock();
+			preempt_enable();
 			goto retry;
 		}
 
@@ -677,6 +696,7 @@ retry:
 		}
 	}
 	rcu_read_unlock();
+	preempt_enable();
 	return ctx;
 }
 
@@ -826,6 +846,15 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
 }
 
 /*
+ * Initialize event state based on the perf_event_attr::disabled.
+ */
+static inline void perf_event__state_init(struct perf_event *event)
+{
+	event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF :
+					      PERF_EVENT_STATE_INACTIVE;
+}
+
+/*
  * Called at perf_event creation and when events are attached/detached from a
  * group.
  */
@@ -1616,7 +1645,16 @@ static int __perf_event_enable(void *info)
 	struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
 	int err;
 
-	if (WARN_ON_ONCE(!ctx->is_active))
+	/*
+	 * There's a time window between 'ctx->is_active' check
+	 * in perf_event_enable function and this place having:
+	 *   - IRQs on
+	 *   - ctx->lock unlocked
+	 *
+	 * where the task could be killed and 'ctx' deactivated
+	 * by perf_event_exit_task.
+	 */
+	if (!ctx->is_active)
 		return -EINVAL;
 
 	raw_spin_lock(&ctx->lock);
@@ -4544,7 +4582,7 @@ static void perf_event_task_event(struct perf_task_event *task_event)
 	rcu_read_lock();
 	list_for_each_entry_rcu(pmu, &pmus, entry) {
 		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->active_pmu != pmu)
+		if (cpuctx->unique_pmu != pmu)
 			goto next;
 		perf_event_task_ctx(&cpuctx->ctx, task_event);
 
@@ -4690,7 +4728,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	rcu_read_lock();
 	list_for_each_entry_rcu(pmu, &pmus, entry) {
 		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->active_pmu != pmu)
+		if (cpuctx->unique_pmu != pmu)
 			goto next;
 		perf_event_comm_ctx(&cpuctx->ctx, comm_event);
 
@@ -4886,7 +4924,7 @@ got_name:
 	rcu_read_lock();
 	list_for_each_entry_rcu(pmu, &pmus, entry) {
 		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->active_pmu != pmu)
+		if (cpuctx->unique_pmu != pmu)
 			goto next;
 		perf_event_mmap_ctx(&cpuctx->ctx, mmap_event,
 					vma->vm_flags & VM_EXEC);
@@ -5912,8 +5950,8 @@ static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu)
 
 		cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu);
 
-		if (cpuctx->active_pmu == old_pmu)
-			cpuctx->active_pmu = pmu;
+		if (cpuctx->unique_pmu == old_pmu)
+			cpuctx->unique_pmu = pmu;
 	}
 }
 
@@ -6045,7 +6083,7 @@ skip_type:
 		cpuctx->ctx.pmu = pmu;
 		cpuctx->jiffies_interval = 1;
 		INIT_LIST_HEAD(&cpuctx->rotation_list);
-		cpuctx->active_pmu = pmu;
+		cpuctx->unique_pmu = pmu;
 	}
 
 got_cpu_context:
@@ -6219,8 +6257,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
 
 	event->overflow_handler	= overflow_handler;
 
-	if (attr->disabled)
-		event->state = PERF_EVENT_STATE_OFF;
+	perf_event__state_init(event);
 
 	pmu = NULL;
 
@@ -6594,9 +6631,17 @@ SYSCALL_DEFINE5(perf_event_open,
 
 		mutex_lock(&gctx->mutex);
 		perf_remove_from_context(group_leader);
+
+		/*
+		 * Removing from the context ends up with disabled
+		 * event. What we want here is event in the initial
+		 * startup state, ready to be add into new context.
+		 */
+		perf_event__state_init(group_leader);
 		list_for_each_entry(sibling, &group_leader->sibling_list,
 				    group_entry) {
 			perf_remove_from_context(sibling);
+			perf_event__state_init(sibling);
 			put_ctx(gctx);
 		}
 		mutex_unlock(&gctx->mutex);
@@ -7064,7 +7109,7 @@ inherit_task_group(struct perf_event *event, struct task_struct *parent,
 		 * child.
 		 */
 
-		child_ctx = alloc_perf_context(event->pmu, child);
+		child_ctx = alloc_perf_context(parent_ctx->pmu, child);
 		if (!child_ctx)
 			return -ENOMEM;
 
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index 086adf2..d99cb4b 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -147,7 +147,7 @@ fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp,
 		return;
 	}
 
-	for_each_online_cpu(cpu) {
+	for_each_possible_cpu(cpu) {
 		unsigned int nr;
 
 		nr = per_cpu(nr_cpu_bp_pinned[type], cpu);
@@ -233,7 +233,7 @@ toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type,
 	if (cpu >= 0) {
 		toggle_bp_task_slot(bp, cpu, enable, type, weight);
 	} else {
-		for_each_online_cpu(cpu)
+		for_each_possible_cpu(cpu)
 			toggle_bp_task_slot(bp, cpu, enable, type, weight);
 	}
 
diff --git a/kernel/futex.c b/kernel/futex.c
index ec372fd..c7c19cb 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -60,6 +60,7 @@
 #include <linux/pid.h>
 #include <linux/nsproxy.h>
 #include <linux/ptrace.h>
+#include <linux/hugetlb.h>
 
 #include <asm/futex.h>
 
@@ -363,7 +364,7 @@ again:
 	} else {
 		key->both.offset |= FUT_OFF_INODE; /* inode-based key */
 		key->shared.inode = page_head->mapping->host;
-		key->shared.pgoff = page_head->index;
+		key->shared.pgoff = basepage_index(page);
 	}
 
 	get_futex_key_refs(key);
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 65a3195..4407e3e 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -62,6 +62,7 @@
 DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
 {
 
+	.lock = __RAW_SPIN_LOCK_UNLOCKED(hrtimer_bases.lock),
 	.clock_base =
 	{
 		{
@@ -298,6 +299,10 @@ ktime_t ktime_sub_ns(const ktime_t kt, u64 nsec)
 	} else {
 		unsigned long rem = do_div(nsec, NSEC_PER_SEC);
 
+		/* Make sure nsec fits into long */
+		if (unlikely(nsec > KTIME_SEC_MAX))
+			return (ktime_t){ .tv64 = KTIME_MAX };
+
 		tmp = ktime_set((long)nsec, rem);
 	}
 
@@ -641,21 +646,9 @@ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
  * and expiry check is done in the hrtimer_interrupt or in the softirq.
  */
 static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
-					    struct hrtimer_clock_base *base,
-					    int wakeup)
+					    struct hrtimer_clock_base *base)
 {
-	if (base->cpu_base->hres_active && hrtimer_reprogram(timer, base)) {
-		if (wakeup) {
-			raw_spin_unlock(&base->cpu_base->lock);
-			raise_softirq_irqoff(HRTIMER_SOFTIRQ);
-			raw_spin_lock(&base->cpu_base->lock);
-		} else
-			__raise_softirq_irqoff(HRTIMER_SOFTIRQ);
-
-		return 1;
-	}
-
-	return 0;
+	return base->cpu_base->hres_active && hrtimer_reprogram(timer, base);
 }
 
 static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
@@ -715,17 +708,20 @@ static int hrtimer_switch_to_hres(void)
 	return 1;
 }
 
+static void clock_was_set_work(struct work_struct *work)
+{
+	clock_was_set();
+}
+
+static DECLARE_WORK(hrtimer_work, clock_was_set_work);
+
 /*
- * Called from timekeeping code to reprogramm the hrtimer interrupt
- * device. If called from the timer interrupt context we defer it to
- * softirq context.
+ * Called from timekeeping and resume code to reprogramm the hrtimer
+ * interrupt device on all cpus.
  */
 void clock_was_set_delayed(void)
 {
-	struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
-
-	cpu_base->clock_was_set = 1;
-	__raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+	schedule_work(&hrtimer_work);
 }
 
 #else
@@ -736,8 +732,7 @@ static inline int hrtimer_switch_to_hres(void) { return 0; }
 static inline void
 hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
 static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
-					    struct hrtimer_clock_base *base,
-					    int wakeup)
+					    struct hrtimer_clock_base *base)
 {
 	return 0;
 }
@@ -775,8 +770,10 @@ void hrtimers_resume(void)
 	WARN_ONCE(!irqs_disabled(),
 		  KERN_INFO "hrtimers_resume() called with IRQs enabled!");
 
+	/* Retrigger on the local CPU */
 	retrigger_next_event(NULL);
-	timerfd_clock_was_set();
+	/* And schedule a retrigger for all others */
+	clock_was_set_delayed();
 }
 
 static inline void timer_stats_hrtimer_set_start_info(struct hrtimer *timer)
@@ -996,8 +993,21 @@ int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
 	 *
 	 * XXX send_remote_softirq() ?
 	 */
-	if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases))
-		hrtimer_enqueue_reprogram(timer, new_base, wakeup);
+	if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases)
+		&& hrtimer_enqueue_reprogram(timer, new_base)) {
+		if (wakeup) {
+			/*
+			 * We need to drop cpu_base->lock to avoid a
+			 * lock ordering issue vs. rq->lock.
+			 */
+			raw_spin_unlock(&new_base->cpu_base->lock);
+			raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+			local_irq_restore(flags);
+			return ret;
+		} else {
+			__raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+		}
+	}
 
 	unlock_hrtimer_base(timer, &flags);
 
@@ -1310,6 +1320,8 @@ retry:
 
 				expires = ktime_sub(hrtimer_get_expires(timer),
 						    base->offset);
+				if (expires.tv64 < 0)
+					expires.tv64 = KTIME_MAX;
 				if (expires.tv64 < expires_next.tv64)
 					expires_next = expires;
 				break;
@@ -1412,13 +1424,6 @@ void hrtimer_peek_ahead_timers(void)
 
 static void run_hrtimer_softirq(struct softirq_action *h)
 {
-	struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
-
-	if (cpu_base->clock_was_set) {
-		cpu_base->clock_was_set = 0;
-		clock_was_set();
-	}
-
 	hrtimer_peek_ahead_timers();
 }
 
@@ -1643,8 +1648,6 @@ static void __cpuinit init_hrtimers_cpu(int cpu)
 	struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
 	int i;
 
-	raw_spin_lock_init(&cpu_base->lock);
-
 	for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
 		cpu_base->clock_base[i].cpu_base = cpu_base;
 		timerqueue_init_head(&cpu_base->clock_base[i].active);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 3e1bdf9..2f61278 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -536,9 +536,9 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
 		return 0;
 
 	if (irq_settings_can_request(desc)) {
-		if (desc->action)
-			if (irqflags & desc->action->flags & IRQF_SHARED)
-				canrequest =1;
+		if (!desc->action ||
+		    irqflags & desc->action->flags & IRQF_SHARED)
+			canrequest = 1;
 	}
 	irq_put_desc_unlock(desc, flags);
 	return canrequest;
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index dc813a9..63633a3 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -80,13 +80,11 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force)
 
 	/*
 	 * All handlers must agree on IRQF_SHARED, so we test just the
-	 * first. Check for action->next as well.
+	 * first.
 	 */
 	action = desc->action;
 	if (!action || !(action->flags & IRQF_SHARED) ||
-	    (action->flags & __IRQF_TIMER) ||
-	    (action->handler(irq, action->dev_id) == IRQ_HANDLED) ||
-	    !action->next)
+	    (action->flags & __IRQF_TIMER))
 		goto out;
 
 	/* Already running on another processor */
@@ -104,6 +102,7 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force)
 	do {
 		if (handle_irq_event(desc) == IRQ_HANDLED)
 			ret = IRQ_HANDLED;
+		/* Make sure that there is still a valid action */
 		action = desc->action;
 	} while ((desc->istate & IRQS_PENDING) && action);
 	desc->istate &= ~IRQS_POLL_INPROGRESS;
diff --git a/kernel/kmod.c b/kernel/kmod.c
index fabfe54..f625b4f 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -421,6 +421,11 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info,
 	int retval = 0;
 
 	helper_lock();
+	if (!sub_info->path) {
+		retval = -EINVAL;
+		goto out;
+	}
+
 	if (sub_info->path[0] == '\0')
 		goto out;
 
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 640ded8..93d5e4a 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -1450,8 +1450,10 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
 		while (!signal_pending(current)) {
 			if (timer.it.cpu.expires.sched == 0) {
 				/*
-				 * Our timer fired and was reset.
+				 * Our timer fired and was reset, below
+				 * deletion can not fail.
 				 */
+				posix_cpu_timer_del(&timer);
 				spin_unlock_irq(&timer.it_lock);
 				return 0;
 			}
@@ -1469,9 +1471,26 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
 		 * We were interrupted by a signal.
 		 */
 		sample_to_timespec(which_clock, timer.it.cpu.expires, rqtp);
-		posix_cpu_timer_set(&timer, 0, &zero_it, it);
+		error = posix_cpu_timer_set(&timer, 0, &zero_it, it);
+		if (!error) {
+			/*
+			 * Timer is now unarmed, deletion can not fail.
+			 */
+			posix_cpu_timer_del(&timer);
+		}
 		spin_unlock_irq(&timer.it_lock);
 
+		while (error == TIMER_RETRY) {
+			/*
+			 * We need to handle case when timer was or is in the
+			 * middle of firing. In other cases we already freed
+			 * resources.
+			 */
+			spin_lock_irq(&timer.it_lock);
+			error = posix_cpu_timer_del(&timer);
+			spin_unlock_irq(&timer.it_lock);
+		}
+
 		if ((it->it_value.tv_sec | it->it_value.tv_nsec) == 0) {
 			/*
 			 * It actually did fire already.
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 4556182..d2da8ad 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -639,6 +639,13 @@ static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
 {
 	struct k_itimer *timr;
 
+	/*
+	 * timer_t could be any type >= int and we want to make sure any
+	 * @timer_id outside positive int range fails lookup.
+	 */
+	if ((unsigned long long)timer_id > INT_MAX)
+		return NULL;
+
 	rcu_read_lock();
 	timr = idr_find(&posix_timers_id, (int)timer_id);
 	if (timr) {
diff --git a/kernel/printk.c b/kernel/printk.c
index 17b0c7a..d614ccd 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -684,8 +684,19 @@ static void call_console_drivers(unsigned start, unsigned end)
 	start_print = start;
 	while (cur_index != end) {
 		if (msg_level < 0 && ((end - cur_index) > 2)) {
+			/*
+			 * prepare buf_prefix, as a contiguous array,
+			 * to be processed by log_prefix function
+			 */
+			char buf_prefix[SYSLOG_PRI_MAX_LENGTH+1];
+			unsigned i;
+			for (i = 0; i < ((end - cur_index)) && (i < SYSLOG_PRI_MAX_LENGTH); i++) {
+				buf_prefix[i] = LOG_BUF(cur_index + i);
+			}
+			buf_prefix[i] = '\0'; /* force '\0' as last string character */
+
 			/* strip log prefix */
-			cur_index += log_prefix(&LOG_BUF(cur_index), &msg_level, NULL);
+			cur_index += log_prefix((const char *)&buf_prefix, &msg_level, NULL);
 			start_print = cur_index;
 		}
 		while (cur_index != end) {
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 2df1157..40581ee 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -38,6 +38,36 @@ void __ptrace_link(struct task_struct *child, struct task_struct *new_parent)
 	child->parent = new_parent;
 }
 
+/* Ensure that nothing can wake it up, even SIGKILL */
+static bool ptrace_freeze_traced(struct task_struct *task)
+{
+	bool ret = false;
+
+	spin_lock_irq(&task->sighand->siglock);
+	if (task_is_traced(task) && !__fatal_signal_pending(task)) {
+		task->state = __TASK_TRACED;
+		ret = true;
+	}
+	spin_unlock_irq(&task->sighand->siglock);
+
+	return ret;
+}
+
+static void ptrace_unfreeze_traced(struct task_struct *task)
+{
+	if (task->state != __TASK_TRACED)
+		return;
+
+	WARN_ON(!task->ptrace || task->parent != current);
+
+	spin_lock_irq(&task->sighand->siglock);
+	if (__fatal_signal_pending(task))
+		wake_up_state(task, __TASK_TRACED);
+	else
+		task->state = TASK_TRACED;
+	spin_unlock_irq(&task->sighand->siglock);
+}
+
 /**
  * __ptrace_unlink - unlink ptracee and restore its execution state
  * @child: ptracee to be unlinked
@@ -92,7 +122,7 @@ void __ptrace_unlink(struct task_struct *child)
 	 * TASK_KILLABLE sleeps.
 	 */
 	if (child->group_stop & GROUP_STOP_PENDING || task_is_traced(child))
-		signal_wake_up(child, task_is_traced(child));
+		ptrace_signal_wake_up(child, true);
 
 	spin_unlock(&child->sighand->siglock);
 }
@@ -112,23 +142,29 @@ int ptrace_check_attach(struct task_struct *child, int kill)
 	 * be changed by us so it's not changing right after this.
 	 */
 	read_lock(&tasklist_lock);
-	if ((child->ptrace & PT_PTRACED) && child->parent == current) {
+	if (child->ptrace && child->parent == current) {
+		WARN_ON(child->state == __TASK_TRACED);
 		/*
 		 * child->sighand can't be NULL, release_task()
 		 * does ptrace_unlink() before __exit_signal().
 		 */
-		spin_lock_irq(&child->sighand->siglock);
-		WARN_ON_ONCE(task_is_stopped(child));
-		if (task_is_traced(child) || kill)
+		if (kill || ptrace_freeze_traced(child))
 			ret = 0;
-		spin_unlock_irq(&child->sighand->siglock);
 	}
 	read_unlock(&tasklist_lock);
 
-	if (!ret && !kill)
-		ret = wait_task_inactive(child, TASK_TRACED) ? 0 : -ESRCH;
+	if (!ret && !kill) {
+		if (!wait_task_inactive(child, __TASK_TRACED)) {
+			/*
+			 * This can only happen if may_ptrace_stop() fails and
+			 * ptrace_stop() changes ->state back to TASK_RUNNING,
+			 * so we should not worry about leaking __TASK_TRACED.
+			 */
+			WARN_ON(child->state == __TASK_TRACED);
+			ret = -ESRCH;
+		}
+	}
 
-	/* All systems go.. */
 	return ret;
 }
 
@@ -245,7 +281,7 @@ static int ptrace_attach(struct task_struct *task)
 	 */
 	if (task_is_stopped(task)) {
 		task->group_stop |= GROUP_STOP_PENDING | GROUP_STOP_TRAPPING;
-		signal_wake_up(task, 1);
+		signal_wake_up_state(task, __TASK_STOPPED);
 		wait_trap = true;
 	}
 
@@ -777,6 +813,8 @@ SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
 		goto out_put_task_struct;
 
 	ret = arch_ptrace(child, request, addr, data);
+	if (ret || request != PTRACE_DETACH)
+		ptrace_unfreeze_traced(child);
 
  out_put_task_struct:
 	put_task_struct(child);
@@ -915,8 +953,11 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
 	}
 
 	ret = ptrace_check_attach(child, request == PTRACE_KILL);
-	if (!ret)
+	if (!ret) {
 		ret = compat_arch_ptrace(child, request, addr, data);
+		if (ret || request != PTRACE_DETACH)
+			ptrace_unfreeze_traced(child);
+	}
 
  out_put_task_struct:
 	put_task_struct(child);
diff --git a/kernel/relay.c b/kernel/relay.c
index 2c242fb..a5be9af 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -1235,6 +1235,7 @@ static ssize_t subbuf_splice_actor(struct file *in,
 	struct splice_pipe_desc spd = {
 		.pages = pages,
 		.nr_pages = 0,
+		.nr_pages_max = PIPE_DEF_BUFFERS,
 		.partial = partial,
 		.flags = flags,
 		.ops = &relay_pipe_buf_ops,
@@ -1302,8 +1303,8 @@ static ssize_t subbuf_splice_actor(struct file *in,
                 ret += padding;
 
 out:
-	splice_shrink_spd(pipe, &spd);
-        return ret;
+	splice_shrink_spd(&spd);
+	return ret;
 }
 
 static ssize_t relay_file_splice_read(struct file *in,
diff --git a/kernel/sched.c b/kernel/sched.c
index e0c9d50..0b0d3dc 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2746,8 +2746,10 @@ static void try_to_wake_up_local(struct task_struct *p)
 {
 	struct rq *rq = task_rq(p);
 
-	BUG_ON(rq != this_rq());
-	BUG_ON(p == current);
+	if (WARN_ON_ONCE(rq != this_rq()) ||
+	    WARN_ON_ONCE(p == current))
+		return;
+
 	lockdep_assert_held(&rq->lock);
 
 	if (!raw_spin_trylock(&p->pi_lock)) {
@@ -2781,7 +2783,8 @@ out:
  */
 int wake_up_process(struct task_struct *p)
 {
-	return try_to_wake_up(p, TASK_ALL, 0);
+	WARN_ON(task_is_stopped_or_traced(p));
+	return try_to_wake_up(p, TASK_NORMAL, 0);
 }
 EXPORT_SYMBOL(wake_up_process);
 
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index a4cc338..e17ec39 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -164,10 +164,36 @@ static u64 sched_clock_remote(struct sched_clock_data *scd)
 	u64 this_clock, remote_clock;
 	u64 *ptr, old_val, val;
 
+#if BITS_PER_LONG != 64
+again:
+	/*
+	 * Careful here: The local and the remote clock values need to
+	 * be read out atomic as we need to compare the values and
+	 * then update either the local or the remote side. So the
+	 * cmpxchg64 below only protects one readout.
+	 *
+	 * We must reread via sched_clock_local() in the retry case on
+	 * 32bit as an NMI could use sched_clock_local() via the
+	 * tracer and hit between the readout of
+	 * the low32bit and the high 32bit portion.
+	 */
+	this_clock = sched_clock_local(my_scd);
+	/*
+	 * We must enforce atomic readout on 32bit, otherwise the
+	 * update on the remote cpu can hit inbetween the readout of
+	 * the low32bit and the high 32bit portion.
+	 */
+	remote_clock = cmpxchg64(&scd->clock, 0, 0);
+#else
+	/*
+	 * On 64bit the read of [my]scd->clock is atomic versus the
+	 * update, so we can avoid the above 32bit dance.
+	 */
 	sched_clock_local(my_scd);
 again:
 	this_clock = my_scd->clock;
 	remote_clock = scd->clock;
+#endif
 
 	/*
 	 * Use the opportunity that we have both locks
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index c768588..fae7d67 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -4277,7 +4277,7 @@ static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task
 	 * idle runqueue:
 	 */
 	if (rq->cfs.load.weight)
-		rr_interval = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
+		rr_interval = NS_TO_JIFFIES(sched_slice(cfs_rq_of(se), se));
 
 	return rr_interval;
 }
diff --git a/kernel/signal.c b/kernel/signal.c
index 81ff97a..f15021b 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -437,7 +437,7 @@ flush_signal_handlers(struct task_struct *t, int force_default)
 		if (force_default || ka->sa.sa_handler != SIG_IGN)
 			ka->sa.sa_handler = SIG_DFL;
 		ka->sa.sa_flags = 0;
-#ifdef SA_RESTORER
+#ifdef __ARCH_HAS_SA_RESTORER
 		ka->sa.sa_restorer = NULL;
 #endif
 		sigemptyset(&ka->sa.sa_mask);
@@ -634,23 +634,17 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
  * No need to set need_resched since signal event passing
  * goes through ->blocked
  */
-void signal_wake_up(struct task_struct *t, int resume)
+void signal_wake_up_state(struct task_struct *t, unsigned int state)
 {
-	unsigned int mask;
-
 	set_tsk_thread_flag(t, TIF_SIGPENDING);
-
 	/*
-	 * For SIGKILL, we want to wake it up in the stopped/traced/killable
+	 * TASK_WAKEKILL also means wake it up in the stopped/traced/killable
 	 * case. We don't check t->state here because there is a race with it
 	 * executing another processor and just now entering stopped state.
 	 * By using wake_up_state, we ensure the process will wake up and
 	 * handle its death signal.
 	 */
-	mask = TASK_INTERRUPTIBLE;
-	if (resume)
-		mask |= TASK_WAKEKILL;
-	if (!wake_up_state(t, mask))
+	if (!wake_up_state(t, state | TASK_INTERRUPTIBLE))
 		kick_process(t);
 }
 
@@ -1678,6 +1672,10 @@ static inline int may_ptrace_stop(void)
 	 * If SIGKILL was already sent before the caller unlocked
 	 * ->siglock we must see ->core_state != NULL. Otherwise it
 	 * is safe to enter schedule().
+	 *
+	 * This is almost outdated, a task with the pending SIGKILL can't
+	 * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported
+	 * after SIGKILL was already dequeued.
 	 */
 	if (unlikely(current->mm->core_state) &&
 	    unlikely(current->mm == current->parent->mm))
@@ -1809,6 +1807,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
 		if (gstop_done)
 			do_notify_parent_cldstop(current, false, why);
 
+		/* tasklist protects us from ptrace_freeze_traced() */
 		__set_current_state(TASK_RUNNING);
 		if (clear_code)
 			current->exit_code = 0;
@@ -2665,7 +2664,7 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
 
 static int do_tkill(pid_t tgid, pid_t pid, int sig)
 {
-	struct siginfo info;
+	struct siginfo info = {};
 
 	info.si_signo = sig;
 	info.si_errno = 0;
diff --git a/kernel/sys.c b/kernel/sys.c
index a04708d..be53817 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -320,7 +320,6 @@ void kernel_restart_prepare(char *cmd)
 	system_state = SYSTEM_RESTART;
 	usermodehelper_disable();
 	device_shutdown();
-	syscore_shutdown();
 }
 
 /**
@@ -365,6 +364,7 @@ static void kernel_shutdown_prepare(enum system_states state)
 void kernel_halt(void)
 {
 	kernel_shutdown_prepare(SYSTEM_HALT);
+	disable_nonboot_cpus();
 	syscore_shutdown();
 	printk(KERN_EMERG "System halted.\n");
 	kmsg_dump(KMSG_DUMP_HALT);
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index e055e8b..17c20c7 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -1194,9 +1194,10 @@ static ssize_t bin_dn_node_address(struct file *file,
 
 		/* Convert the decnet address to binary */
 		result = -EIO;
-		nodep = strchr(buf, '.') + 1;
+		nodep = strchr(buf, '.');
 		if (!nodep)
 			goto out;
+		++nodep;
 
 		area = simple_strtoul(buf, NULL, 10);
 		node = simple_strtoul(nodep, NULL, 10);
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 7a90d02..20ba7b4 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -66,12 +66,17 @@ static void tick_broadcast_start_periodic(struct clock_event_device *bc)
  */
 int tick_check_broadcast_device(struct clock_event_device *dev)
 {
-	if ((tick_broadcast_device.evtdev &&
+	struct clock_event_device *cur = tick_broadcast_device.evtdev;
+
+	if ((dev->features & CLOCK_EVT_FEAT_DUMMY) ||
+	    (tick_broadcast_device.evtdev &&
 	     tick_broadcast_device.evtdev->rating >= dev->rating) ||
 	     (dev->features & CLOCK_EVT_FEAT_C3STOP))
 		return 0;
 
 	clockevents_exchange_device(tick_broadcast_device.evtdev, dev);
+	if (cur)
+		cur->event_handler = clockevents_handle_noop;
 	tick_broadcast_device.evtdev = dev;
 	if (!cpumask_empty(tick_get_broadcast_mask()))
 		tick_broadcast_start_periodic(dev);
@@ -391,7 +396,15 @@ void tick_check_oneshot_broadcast(int cpu)
 	if (cpumask_test_cpu(cpu, to_cpumask(tick_broadcast_oneshot_mask))) {
 		struct tick_device *td = &per_cpu(tick_cpu_device, cpu);
 
-		clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_ONESHOT);
+		/*
+		 * We might be in the middle of switching over from
+		 * periodic to oneshot. If the CPU has not yet
+		 * switched over, leave the device alone.
+		 */
+		if (td->mode == TICKDEV_MODE_ONESHOT) {
+			clockevents_set_mode(td->evtdev,
+					     CLOCK_EVT_MODE_ONESHOT);
+		}
 	}
 }
 
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 119528d..c43b479 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -323,6 +323,7 @@ static void tick_shutdown(unsigned int *cpup)
 		 */
 		dev->mode = CLOCK_EVT_MODE_UNUSED;
 		clockevents_exchange_device(dev, NULL);
+		dev->event_handler = clockevents_handle_noop;
 		td->evtdev = NULL;
 	}
 	raw_spin_unlock_irqrestore(&tick_device_lock, flags);
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index c473ce2..c0be5f2 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -811,7 +811,7 @@ void tick_cancel_sched_timer(int cpu)
 		hrtimer_cancel(&ts->sched_timer);
 # endif
 
-	ts->nohz_mode = NOHZ_MODE_INACTIVE;
+	memset(ts, 0, sizeof(*ts));
 }
 #endif
 
diff --git a/kernel/timer.c b/kernel/timer.c
index 27982d9..5eac0d8 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -145,9 +145,11 @@ static unsigned long round_jiffies_common(unsigned long j, int cpu,
 	/* now that we have rounded, subtract the extra skew again */
 	j -= cpu * 3;
 
-	if (j <= jiffies) /* rounding ate our timeout entirely; */
-		return original;
-	return j;
+	/*
+	 * Make sure j is still in the future. Otherwise return the
+	 * unmodified value.
+	 */
+	return time_is_after_jiffies(j) ? j : original;
 }
 
 /**
@@ -1630,12 +1632,12 @@ static int __cpuinit init_timers_cpu(int cpu)
 			boot_done = 1;
 			base = &boot_tvec_bases;
 		}
+		spin_lock_init(&base->lock);
 		tvec_base_done[cpu] = 1;
 	} else {
 		base = per_cpu(tvec_bases, cpu);
 	}
 
-	spin_lock_init(&base->lock);
 
 	for (j = 0; j < TVN_SIZE; j++) {
 		INIT_LIST_HEAD(base->tv5.vec + j);
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 2ad39e5..57c92f2 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -386,24 +386,28 @@ config KPROBE_EVENT
 	  If you want to use perf tools, this option is strongly recommended.
 
 config DYNAMIC_FTRACE
-	bool "enable/disable ftrace tracepoints dynamically"
+	bool "enable/disable function tracing dynamically"
 	depends on FUNCTION_TRACER
 	depends on HAVE_DYNAMIC_FTRACE
 	default y
 	help
-          This option will modify all the calls to ftrace dynamically
-	  (will patch them out of the binary image and replace them
-	  with a No-Op instruction) as they are called. A table is
-	  created to dynamically enable them again.
+	  This option will modify all the calls to function tracing
+	  dynamically (will patch them out of the binary image and
+	  replace them with a No-Op instruction) on boot up. During
+	  compile time, a table is made of all the locations that ftrace
+	  can function trace, and this table is linked into the kernel
+	  image. When this is enabled, functions can be individually
+	  enabled, and the functions not enabled will not affect
+	  performance of the system.
+
+	  See the files in /sys/kernel/debug/tracing:
+	    available_filter_functions
+	    set_ftrace_filter
+	    set_ftrace_notrace
 
 	  This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but
 	  otherwise has native performance as long as no tracing is active.
 
-	  The changes to the code are done by a kernel thread that
-	  wakes up once a second and checks to see if any ftrace calls
-	  were made. If so, it runs stop_machine (stops all CPUS)
-	  and modifies the code to jump over the call to ftrace.
-
 config FUNCTION_PROFILER
 	bool "Kernel function profiler"
 	depends on FUNCTION_TRACER
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index e96eee3..0d704b0 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -548,7 +548,7 @@ int ftrace_profile_pages_init(struct ftrace_profile_stat *stat)
 
 	pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE);
 
-	for (i = 0; i < pages; i++) {
+	for (i = 1; i < pages; i++) {
 		pg->next = (void *)get_zeroed_page(GFP_KERNEL);
 		if (!pg->next)
 			goto out_free;
@@ -566,7 +566,6 @@ int ftrace_profile_pages_init(struct ftrace_profile_stat *stat)
 		free_page(tmp);
 	}
 
-	free_page((unsigned long)stat->pages);
 	stat->pages = NULL;
 	stat->start = NULL;
 
@@ -934,6 +933,19 @@ static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
 
 static struct pid * const ftrace_swapper_pid = &init_struct_pid;
 
+static loff_t
+ftrace_filter_lseek(struct file *file, loff_t offset, int whence)
+{
+	loff_t ret;
+
+	if (file->f_mode & FMODE_READ)
+		ret = seq_lseek(file, offset, whence);
+	else
+		file->f_pos = ret = 1;
+
+	return ret;
+}
+
 #ifdef CONFIG_DYNAMIC_FTRACE
 
 #ifndef CONFIG_FTRACE_MCOUNT_RECORD
@@ -2300,19 +2312,6 @@ ftrace_notrace_open(struct inode *inode, struct file *file)
 				 inode, file);
 }
 
-static loff_t
-ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
-{
-	loff_t ret;
-
-	if (file->f_mode & FMODE_READ)
-		ret = seq_lseek(file, offset, origin);
-	else
-		file->f_pos = ret = 1;
-
-	return ret;
-}
-
 static int ftrace_match(char *str, char *regex, int len, int type)
 {
 	int matched = 0;
@@ -2709,8 +2708,8 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 					continue;
 			}
 
-			hlist_del(&entry->node);
-			call_rcu(&entry->rcu, ftrace_free_entry_rcu);
+			hlist_del_rcu(&entry->node);
+			call_rcu_sched(&entry->rcu, ftrace_free_entry_rcu);
 		}
 	}
 	__disable_ftrace_function_probe();
@@ -3119,7 +3118,7 @@ static const struct file_operations ftrace_filter_fops = {
 	.open = ftrace_filter_open,
 	.read = seq_read,
 	.write = ftrace_filter_write,
-	.llseek = ftrace_regex_lseek,
+	.llseek = ftrace_filter_lseek,
 	.release = ftrace_regex_release,
 };
 
@@ -3127,7 +3126,7 @@ static const struct file_operations ftrace_notrace_fops = {
 	.open = ftrace_notrace_open,
 	.read = seq_read,
 	.write = ftrace_notrace_write,
-	.llseek = ftrace_regex_lseek,
+	.llseek = ftrace_filter_lseek,
 	.release = ftrace_regex_release,
 };
 
@@ -3288,7 +3287,8 @@ out:
 	if (fail)
 		return -EINVAL;
 
-	ftrace_graph_filter_enabled = 1;
+	ftrace_graph_filter_enabled = !!(*idx);
+
 	return 0;
 }
 
@@ -3335,8 +3335,8 @@ static const struct file_operations ftrace_graph_fops = {
 	.open		= ftrace_graph_open,
 	.read		= seq_read,
 	.write		= ftrace_graph_write,
+	.llseek		= ftrace_filter_lseek,
 	.release	= ftrace_graph_release,
-	.llseek		= seq_lseek,
 };
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 
@@ -3432,37 +3432,51 @@ static void ftrace_init_module(struct module *mod,
 	ftrace_process_locs(mod, start, end);
 }
 
-static int ftrace_module_notify(struct notifier_block *self,
-				unsigned long val, void *data)
+static int ftrace_module_notify_enter(struct notifier_block *self,
+				      unsigned long val, void *data)
 {
 	struct module *mod = data;
 
-	switch (val) {
-	case MODULE_STATE_COMING:
+	if (val == MODULE_STATE_COMING)
 		ftrace_init_module(mod, mod->ftrace_callsites,
 				   mod->ftrace_callsites +
 				   mod->num_ftrace_callsites);
-		break;
-	case MODULE_STATE_GOING:
+	return 0;
+}
+
+static int ftrace_module_notify_exit(struct notifier_block *self,
+				     unsigned long val, void *data)
+{
+	struct module *mod = data;
+
+	if (val == MODULE_STATE_GOING)
 		ftrace_release_mod(mod);
-		break;
-	}
 
 	return 0;
 }
 #else
-static int ftrace_module_notify(struct notifier_block *self,
-				unsigned long val, void *data)
+static int ftrace_module_notify_enter(struct notifier_block *self,
+				      unsigned long val, void *data)
+{
+	return 0;
+}
+static int ftrace_module_notify_exit(struct notifier_block *self,
+				     unsigned long val, void *data)
 {
 	return 0;
 }
 #endif /* CONFIG_MODULES */
 
-struct notifier_block ftrace_module_nb = {
-	.notifier_call = ftrace_module_notify,
+struct notifier_block ftrace_module_enter_nb = {
+	.notifier_call = ftrace_module_notify_enter,
 	.priority = INT_MAX,	/* Run before anything that can use kprobes */
 };
 
+struct notifier_block ftrace_module_exit_nb = {
+	.notifier_call = ftrace_module_notify_exit,
+	.priority = INT_MIN,	/* Run after anything that can remove kprobes */
+};
+
 extern unsigned long __start_mcount_loc[];
 extern unsigned long __stop_mcount_loc[];
 
@@ -3494,9 +3508,13 @@ void __init ftrace_init(void)
 				  __start_mcount_loc,
 				  __stop_mcount_loc);
 
-	ret = register_module_notifier(&ftrace_module_nb);
+	ret = register_module_notifier(&ftrace_module_enter_nb);
+	if (ret)
+		pr_warning("Failed to register trace ftrace module enter notifier\n");
+
+	ret = register_module_notifier(&ftrace_module_exit_nb);
 	if (ret)
-		pr_warning("Failed to register trace ftrace module notifier\n");
+		pr_warning("Failed to register trace ftrace module exit notifier\n");
 
 	set_ftrace_early_filters();
 
@@ -3804,7 +3822,7 @@ static const struct file_operations ftrace_pid_fops = {
 	.open		= ftrace_pid_open,
 	.write		= ftrace_pid_write,
 	.read		= seq_read,
-	.llseek		= seq_lseek,
+	.llseek		= ftrace_filter_lseek,
 	.release	= ftrace_pid_release,
 };
 
@@ -3916,12 +3934,8 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
 		ftrace_startup_sysctl();
 
 		/* we are starting ftrace again */
-		if (ftrace_ops_list != &ftrace_list_end) {
-			if (ftrace_ops_list->next == &ftrace_list_end)
-				ftrace_trace_function = ftrace_ops_list->func;
-			else
-				ftrace_trace_function = ftrace_ops_list_func;
-		}
+		if (ftrace_ops_list != &ftrace_list_end)
+			update_ftrace_function();
 
 	} else {
 		/* stopping ftrace calls (just send to ftrace_stub) */
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 672a749..34d15ba 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -628,7 +628,15 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 
 	memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN);
 	max_data->pid = tsk->pid;
-	max_data->uid = task_uid(tsk);
+	/*
+	 * If tsk == current, then use current_uid(), as that does not use
+	 * RCU. The irq tracer can be called out of RCU scope.
+	 */
+	if (tsk == current)
+		max_data->uid = current_uid();
+	else
+		max_data->uid = task_uid(tsk);
+
 	max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
 	max_data->policy = tsk->policy;
 	max_data->rt_priority = tsk->rt_priority;
@@ -649,7 +657,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 void
 update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 {
-	struct ring_buffer *buf = tr->buffer;
+	struct ring_buffer *buf;
 
 	if (trace_stop_count)
 		return;
@@ -661,6 +669,7 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 	}
 	arch_spin_lock(&ftrace_max_lock);
 
+	buf = tr->buffer;
 	tr->buffer = max_tr.buffer;
 	max_tr.buffer = buf;
 
@@ -2526,11 +2535,25 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
 	return -EINVAL;
 }
 
-static void set_tracer_flags(unsigned int mask, int enabled)
+/* Some tracers require overwrite to stay enabled */
+int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set)
+{
+	if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set)
+		return -1;
+
+	return 0;
+}
+
+int set_tracer_flag(unsigned int mask, int enabled)
 {
 	/* do nothing if flag is already set */
 	if (!!(trace_flags & mask) == !!enabled)
-		return;
+		return 0;
+
+	/* Give the tracer a chance to approve the change */
+	if (current_trace->flag_changed)
+		if (current_trace->flag_changed(current_trace, mask, !!enabled))
+			return -EINVAL;
 
 	if (enabled)
 		trace_flags |= mask;
@@ -2542,6 +2565,8 @@ static void set_tracer_flags(unsigned int mask, int enabled)
 
 	if (mask == TRACE_ITER_OVERWRITE)
 		ring_buffer_change_overwrite(global_trace.buffer, enabled);
+
+	return 0;
 }
 
 static ssize_t
@@ -2551,7 +2576,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
 	char buf[64];
 	char *cmp;
 	int neg = 0;
-	int ret;
+	int ret = -ENODEV;
 	int i;
 
 	if (cnt >= sizeof(buf))
@@ -2568,21 +2593,23 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
 		cmp += 2;
 	}
 
+	mutex_lock(&trace_types_lock);
+
 	for (i = 0; trace_options[i]; i++) {
 		if (strcmp(cmp, trace_options[i]) == 0) {
-			set_tracer_flags(1 << i, !neg);
+			ret = set_tracer_flag(1 << i, !neg);
 			break;
 		}
 	}
 
 	/* If no option could be set, test the specific tracer options */
-	if (!trace_options[i]) {
-		mutex_lock(&trace_types_lock);
+	if (!trace_options[i])
 		ret = set_tracer_option(current_trace, cmp, neg);
-		mutex_unlock(&trace_types_lock);
-		if (ret)
-			return ret;
-	}
+
+	mutex_unlock(&trace_types_lock);
+
+	if (ret < 0)
+		return ret;
 
 	*ppos += cnt;
 
@@ -2880,6 +2907,9 @@ static int tracing_set_tracer(const char *buf)
 		goto out;
 
 	trace_branch_disable();
+
+	current_trace->enabled = false;
+
 	if (current_trace && current_trace->reset)
 		current_trace->reset(tr);
 	if (current_trace && current_trace->use_max_tr) {
@@ -2909,6 +2939,7 @@ static int tracing_set_tracer(const char *buf)
 			goto out;
 	}
 
+	current_trace->enabled = true;
 	trace_branch_enable(tr);
  out:
 	mutex_unlock(&trace_types_lock);
@@ -3214,6 +3245,7 @@ waitagain:
 	memset(&iter->seq, 0,
 	       sizeof(struct trace_iterator) -
 	       offsetof(struct trace_iterator, seq));
+	cpumask_clear(iter->started);
 	iter->pos = -1;
 
 	trace_event_read_lock();
@@ -3332,6 +3364,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 		.pages		= pages_def,
 		.partial	= partial_def,
 		.nr_pages	= 0, /* This gets updated below. */
+		.nr_pages_max	= PIPE_DEF_BUFFERS,
 		.flags		= flags,
 		.ops		= &tracing_pipe_buf_ops,
 		.spd_release	= tracing_spd_release_pipe,
@@ -3403,7 +3436,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 
 	ret = splice_to_pipe(pipe, &spd);
 out:
-	splice_shrink_spd(pipe, &spd);
+	splice_shrink_spd(&spd);
 	return ret;
 
 out_err:
@@ -3816,6 +3849,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 	struct splice_pipe_desc spd = {
 		.pages		= pages_def,
 		.partial	= partial_def,
+		.nr_pages_max	= PIPE_DEF_BUFFERS,
 		.flags		= flags,
 		.ops		= &buffer_pipe_buf_ops,
 		.spd_release	= buffer_spd_release,
@@ -3904,7 +3938,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 	}
 
 	ret = splice_to_pipe(pipe, &spd);
-	splice_shrink_spd(pipe, &spd);
+	splice_shrink_spd(&spd);
 out:
 	return ret;
 }
@@ -4179,7 +4213,13 @@ trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
 
 	if (val != 0 && val != 1)
 		return -EINVAL;
-	set_tracer_flags(1 << index, val);
+
+	mutex_lock(&trace_types_lock);
+	ret = set_tracer_flag(1 << index, val);
+	mutex_unlock(&trace_types_lock);
+
+	if (ret < 0)
+		return ret;
 
 	*ppos += cnt;
 
@@ -4331,6 +4371,8 @@ static __init int tracer_init_debugfs(void)
 	trace_access_lock_init();
 
 	d_tracer = tracing_init_dentry();
+	if (!d_tracer)
+		return 0;
 
 	trace_create_file("tracing_enabled", 0644, d_tracer,
 			&global_trace, &tracing_ctrl_fops);
@@ -4458,30 +4500,32 @@ void trace_init_global_iter(struct trace_iterator *iter)
 	iter->cpu_file = TRACE_PIPE_ALL_CPU;
 }
 
-static void
-__ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
+void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
 {
-	static arch_spinlock_t ftrace_dump_lock =
-		(arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
 	/* use static because iter can be a bit big for the stack */
 	static struct trace_iterator iter;
+	static atomic_t dump_running;
 	unsigned int old_userobj;
-	static int dump_ran;
 	unsigned long flags;
 	int cnt = 0, cpu;
 
-	/* only one dump */
-	local_irq_save(flags);
-	arch_spin_lock(&ftrace_dump_lock);
-	if (dump_ran)
-		goto out;
-
-	dump_ran = 1;
+	/* Only allow one dump user at a time. */
+	if (atomic_inc_return(&dump_running) != 1) {
+		atomic_dec(&dump_running);
+		return;
+	}
 
+	/*
+	 * Always turn off tracing when we dump.
+	 * We don't need to show trace output of what happens
+	 * between multiple crashes.
+	 *
+	 * If the user does a sysrq-z, then they can re-enable
+	 * tracing with echo 1 > tracing_on.
+	 */
 	tracing_off();
 
-	if (disable_tracing)
-		ftrace_kill();
+	local_irq_save(flags);
 
 	trace_init_global_iter(&iter);
 
@@ -4552,26 +4596,15 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
 		printk(KERN_TRACE "---------------------------------\n");
 
  out_enable:
-	/* Re-enable tracing if requested */
-	if (!disable_tracing) {
-		trace_flags |= old_userobj;
+	trace_flags |= old_userobj;
 
-		for_each_tracing_cpu(cpu) {
-			atomic_dec(&iter.tr->data[cpu]->disabled);
-		}
-		tracing_on();
+	for_each_tracing_cpu(cpu) {
+		atomic_dec(&iter.tr->data[cpu]->disabled);
 	}
-
- out:
-	arch_spin_unlock(&ftrace_dump_lock);
+ 	atomic_dec(&dump_running);
 	local_irq_restore(flags);
 }
-
-/* By default: disable tracing after the dump */
-void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
-{
-	__ftrace_dump(true, oops_dump_mode);
-}
+EXPORT_SYMBOL_GPL(ftrace_dump);
 
 __init static int tracer_alloc_buffers(void)
 {
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index f807407..123ee28 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -271,10 +271,14 @@ struct tracer {
 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
 	/* If you handled the flag setting, return 0 */
 	int			(*set_flag)(u32 old_flags, u32 bit, int set);
+	/* Return 0 if OK with change, else return non-zero */
+	int			(*flag_changed)(struct tracer *tracer,
+						u32 mask, int set);
 	struct tracer		*next;
 	struct tracer_flags	*flags;
 	int			print_max;
 	int			use_max_tr;
+	bool			enabled;
 };
 
 
@@ -776,6 +780,9 @@ extern struct list_head ftrace_events;
 extern const char *__start___trace_bprintk_fmt[];
 extern const char *__stop___trace_bprintk_fmt[];
 
+int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
+int set_tracer_flag(unsigned int mask, int enabled);
+
 #undef FTRACE_ENTRY
 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)		\
 	extern struct ftrace_event_call					\
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index c77424b..984aad8 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -32,7 +32,7 @@ enum {
 
 static int trace_type __read_mostly;
 
-static int save_lat_flag;
+static int save_flags;
 
 static void stop_irqsoff_tracer(struct trace_array *tr, int graph);
 static int start_irqsoff_tracer(struct trace_array *tr, int graph);
@@ -544,8 +544,11 @@ static void stop_irqsoff_tracer(struct trace_array *tr, int graph)
 
 static void __irqsoff_tracer_init(struct trace_array *tr)
 {
-	save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT;
-	trace_flags |= TRACE_ITER_LATENCY_FMT;
+	save_flags = trace_flags;
+
+	/* non overwrite screws up the latency tracers */
+	set_tracer_flag(TRACE_ITER_OVERWRITE, 1);
+	set_tracer_flag(TRACE_ITER_LATENCY_FMT, 1);
 
 	tracing_max_latency = 0;
 	irqsoff_trace = tr;
@@ -559,10 +562,13 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
 
 static void irqsoff_tracer_reset(struct trace_array *tr)
 {
+	int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT;
+	int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE;
+
 	stop_irqsoff_tracer(tr, is_graph());
 
-	if (!save_lat_flag)
-		trace_flags &= ~TRACE_ITER_LATENCY_FMT;
+	set_tracer_flag(TRACE_ITER_LATENCY_FMT, lat_flag);
+	set_tracer_flag(TRACE_ITER_OVERWRITE, overwrite_flag);
 }
 
 static void irqsoff_tracer_start(struct trace_array *tr)
@@ -595,6 +601,7 @@ static struct tracer irqsoff_tracer __read_mostly =
 	.print_line     = irqsoff_print_line,
 	.flags		= &tracer_flags,
 	.set_flag	= irqsoff_set_flag,
+	.flag_changed	= trace_keep_overwrite,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_irqsoff,
 #endif
@@ -628,6 +635,7 @@ static struct tracer preemptoff_tracer __read_mostly =
 	.print_line     = irqsoff_print_line,
 	.flags		= &tracer_flags,
 	.set_flag	= irqsoff_set_flag,
+	.flag_changed	= trace_keep_overwrite,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_preemptoff,
 #endif
@@ -663,6 +671,7 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
 	.print_line     = irqsoff_print_line,
 	.flags		= &tracer_flags,
 	.set_flag	= irqsoff_set_flag,
+	.flag_changed	= trace_keep_overwrite,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_preemptirqsoff,
 #endif
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index f029dd4..1beb25e 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -36,7 +36,7 @@ static void __wakeup_reset(struct trace_array *tr);
 static int wakeup_graph_entry(struct ftrace_graph_ent *trace);
 static void wakeup_graph_return(struct ftrace_graph_ret *trace);
 
-static int save_lat_flag;
+static int save_flags;
 
 #define TRACE_DISPLAY_GRAPH     1
 
@@ -526,8 +526,11 @@ static void stop_wakeup_tracer(struct trace_array *tr)
 
 static int __wakeup_tracer_init(struct trace_array *tr)
 {
-	save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT;
-	trace_flags |= TRACE_ITER_LATENCY_FMT;
+	save_flags = trace_flags;
+
+	/* non overwrite screws up the latency tracers */
+	set_tracer_flag(TRACE_ITER_OVERWRITE, 1);
+	set_tracer_flag(TRACE_ITER_LATENCY_FMT, 1);
 
 	tracing_max_latency = 0;
 	wakeup_trace = tr;
@@ -549,12 +552,15 @@ static int wakeup_rt_tracer_init(struct trace_array *tr)
 
 static void wakeup_tracer_reset(struct trace_array *tr)
 {
+	int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT;
+	int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE;
+
 	stop_wakeup_tracer(tr);
 	/* make sure we put back any tasks we are tracing */
 	wakeup_reset(tr);
 
-	if (!save_lat_flag)
-		trace_flags &= ~TRACE_ITER_LATENCY_FMT;
+	set_tracer_flag(TRACE_ITER_LATENCY_FMT, lat_flag);
+	set_tracer_flag(TRACE_ITER_OVERWRITE, overwrite_flag);
 }
 
 static void wakeup_tracer_start(struct trace_array *tr)
@@ -580,6 +586,7 @@ static struct tracer wakeup_tracer __read_mostly =
 	.print_line	= wakeup_print_line,
 	.flags		= &tracer_flags,
 	.set_flag	= wakeup_set_flag,
+	.flag_changed	= trace_keep_overwrite,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_wakeup,
 #endif
@@ -601,6 +608,7 @@ static struct tracer wakeup_rt_tracer __read_mostly =
 	.print_line	= wakeup_print_line,
 	.flags		= &tracer_flags,
 	.set_flag	= wakeup_set_flag,
+	.flag_changed	= trace_keep_overwrite,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_wakeup,
 #endif
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 288541f..09fd98a 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -461,8 +461,6 @@ 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, enum ftrace_dump_mode oops_dump_mode);
 static unsigned int graph_hang_thresh;
 
 /* Wrap the real function entry probe to avoid possible hanging */
@@ -472,8 +470,11 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace)
 	if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) {
 		ftrace_graph_stop();
 		printk(KERN_WARNING "BUG: Function graph tracer hang!\n");
-		if (ftrace_dump_on_oops)
-			__ftrace_dump(false, DUMP_ALL);
+		if (ftrace_dump_on_oops) {
+			ftrace_dump(DUMP_ALL);
+			/* ftrace_dump() disables tracing */
+			tracing_on();
+		}
 		return 0;
 	}
 
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index b0b53b8..2d43977 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -17,13 +17,24 @@
 
 #define STACK_TRACE_ENTRIES 500
 
+#ifdef CC_USING_FENTRY
+# define fentry		1
+#else
+# define fentry		0
+#endif
+
 static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES+1] =
 	 { [0 ... (STACK_TRACE_ENTRIES)] = ULONG_MAX };
 static unsigned stack_dump_index[STACK_TRACE_ENTRIES];
 
+/*
+ * Reserve one entry for the passed in ip. This will allow
+ * us to remove most or all of the stack size overhead
+ * added by the stack tracer itself.
+ */
 static struct stack_trace max_stack_trace = {
-	.max_entries		= STACK_TRACE_ENTRIES,
-	.entries		= stack_dump_trace,
+	.max_entries		= STACK_TRACE_ENTRIES - 1,
+	.entries		= &stack_dump_trace[1],
 };
 
 static unsigned long max_stack_size;
@@ -37,25 +48,34 @@ static DEFINE_MUTEX(stack_sysctl_mutex);
 int stack_tracer_enabled;
 static int last_stack_tracer_enabled;
 
-static inline void check_stack(void)
+static inline void
+check_stack(unsigned long ip, unsigned long *stack)
 {
 	unsigned long this_size, flags;
 	unsigned long *p, *top, *start;
+	static int tracer_frame;
+	int frame_size = ACCESS_ONCE(tracer_frame);
 	int i;
 
-	this_size = ((unsigned long)&this_size) & (THREAD_SIZE-1);
+	this_size = ((unsigned long)stack) & (THREAD_SIZE-1);
 	this_size = THREAD_SIZE - this_size;
+	/* Remove the frame of the tracer */
+	this_size -= frame_size;
 
 	if (this_size <= max_stack_size)
 		return;
 
 	/* we do not handle interrupt stacks yet */
-	if (!object_is_on_stack(&this_size))
+	if (!object_is_on_stack(stack))
 		return;
 
 	local_irq_save(flags);
 	arch_spin_lock(&max_stack_lock);
 
+	/* In case another CPU set the tracer_frame on us */
+	if (unlikely(!frame_size))
+		this_size -= tracer_frame;
+
 	/* a race could have already updated it */
 	if (this_size <= max_stack_size)
 		goto out;
@@ -68,10 +88,18 @@ static inline void check_stack(void)
 	save_stack_trace(&max_stack_trace);
 
 	/*
+	 * Add the passed in ip from the function tracer.
+	 * Searching for this on the stack will skip over
+	 * most of the overhead from the stack tracer itself.
+	 */
+	stack_dump_trace[0] = ip;
+	max_stack_trace.nr_entries++;
+
+	/*
 	 * Now find where in the stack these are.
 	 */
 	i = 0;
-	start = &this_size;
+	start = stack;
 	top = (unsigned long *)
 		(((unsigned long)start & ~(THREAD_SIZE-1)) + THREAD_SIZE);
 
@@ -95,6 +123,18 @@ static inline void check_stack(void)
 				found = 1;
 				/* Start the search from here */
 				start = p + 1;
+				/*
+				 * We do not want to show the overhead
+				 * of the stack tracer stack in the
+				 * max stack. If we haven't figured
+				 * out what that is, then figure it out
+				 * now.
+				 */
+				if (unlikely(!tracer_frame) && i == 1) {
+					tracer_frame = (p - stack) *
+						sizeof(unsigned long);
+					max_stack_size -= tracer_frame;
+				}
 			}
 		}
 
@@ -110,6 +150,7 @@ static inline void check_stack(void)
 static void
 stack_trace_call(unsigned long ip, unsigned long parent_ip)
 {
+	unsigned long stack;
 	int cpu;
 
 	if (unlikely(!ftrace_enabled || stack_trace_disabled))
@@ -122,7 +163,26 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip)
 	if (per_cpu(trace_active, cpu)++ != 0)
 		goto out;
 
-	check_stack();
+	/*
+	 * When fentry is used, the traced function does not get
+	 * its stack frame set up, and we lose the parent.
+	 * The ip is pretty useless because the function tracer
+	 * was called before that function set up its stack frame.
+	 * In this case, we use the parent ip.
+	 *
+	 * By adding the return address of either the parent ip
+	 * or the current ip we can disregard most of the stack usage
+	 * caused by the stack tracer itself.
+	 *
+	 * The function tracer always reports the address of where the
+	 * mcount call was, but the stack will hold the return address.
+	 */
+	if (fentry)
+		ip = parent_ip;
+	else
+		ip += MCOUNT_INSN_SIZE;
+
+	check_stack(ip, &stack);
 
  out:
 	per_cpu(trace_active, cpu)--;
@@ -360,6 +420,8 @@ static __init int stack_trace_init(void)
 	struct dentry *d_tracer;
 
 	d_tracer = tracing_init_dentry();
+	if (!d_tracer)
+		return 0;
 
 	trace_create_file("stack_max_size", 0644, d_tracer,
 			&max_stack_size, &stack_max_size_fops);
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index 96cffb2..847f88a 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -307,6 +307,8 @@ static int tracing_stat_init(void)
 	struct dentry *d_tracing;
 
 	d_tracing = tracing_init_dentry();
+	if (!d_tracing)
+		return 0;
 
 	stat_dir = debugfs_create_dir("trace_stat", d_tracing);
 	if (!stat_dir)
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index ee7b5a0..5819cd5 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -304,6 +304,8 @@ void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id)
 	struct ring_buffer *buffer;
 	int size;
 	int syscall_nr;
+	unsigned long irq_flags;
+	int pc;
 
 	syscall_nr = syscall_get_nr(current, regs);
 	if (syscall_nr < 0)
@@ -317,8 +319,11 @@ void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id)
 
 	size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
 
+	local_save_flags(irq_flags);
+	pc = preempt_count();
+
 	event = trace_current_buffer_lock_reserve(&buffer,
-			sys_data->enter_event->event.type, size, 0, 0);
+			sys_data->enter_event->event.type, size, irq_flags, pc);
 	if (!event)
 		return;
 
@@ -328,7 +333,8 @@ void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id)
 
 	if (!filter_current_check_discard(buffer, sys_data->enter_event,
 					  entry, event))
-		trace_current_buffer_unlock_commit(buffer, event, 0, 0);
+		trace_current_buffer_unlock_commit(buffer, event,
+						   irq_flags, pc);
 }
 
 void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
@@ -338,6 +344,8 @@ void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
 	struct ring_buffer_event *event;
 	struct ring_buffer *buffer;
 	int syscall_nr;
+	unsigned long irq_flags;
+	int pc;
 
 	syscall_nr = syscall_get_nr(current, regs);
 	if (syscall_nr < 0)
@@ -349,8 +357,12 @@ void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
 	if (!sys_data)
 		return;
 
+	local_save_flags(irq_flags);
+	pc = preempt_count();
+
 	event = trace_current_buffer_lock_reserve(&buffer,
-			sys_data->exit_event->event.type, sizeof(*entry), 0, 0);
+			sys_data->exit_event->event.type, sizeof(*entry),
+			irq_flags, pc);
 	if (!event)
 		return;
 
@@ -360,7 +372,8 @@ void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
 
 	if (!filter_current_check_discard(buffer, sys_data->exit_event,
 					  entry, event))
-		trace_current_buffer_unlock_commit(buffer, event, 0, 0);
+		trace_current_buffer_unlock_commit(buffer, event,
+						   irq_flags, pc);
 }
 
 int reg_event_syscall_enter(struct ftrace_event_call *call)