Merge tag 'v3.10' into sched/core

Merge in a recent upstream commit:

  c2853c8df57f include/linux/math64.h: add div64_ul()

because:

  72a4cf20cb71 sched: Change cfs_rq load avg to unsigned long

relies on it.

[ We don't rebase sched/core for this, because the handful of
  followup commits after the broken commit are not behavioral
  changes so are unlikely to be needed during bisection. ]

Signed-off-by: Ingo Molnar <mingo@kernel.org>

29 files changed, 428 insertions, 236 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index 21c7fa615bd3..91e53d04b6a9 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1056,7 +1056,7 @@ static inline void audit_get_stamp(struct audit_context *ctx,
 static void wait_for_auditd(unsigned long sleep_time)
 {
 	DECLARE_WAITQUEUE(wait, current);
-	set_current_state(TASK_INTERRUPTIBLE);
+	set_current_state(TASK_UNINTERRUPTIBLE);
 	add_wait_queue(&audit_backlog_wait, &wait);
 
 	if (audit_backlog_limit &&
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index a291aa23fb3f..43c307dc9453 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -658,6 +658,7 @@ int audit_add_tree_rule(struct audit_krule *rule)
 	struct vfsmount *mnt;
 	int err;
 
+	rule->tree = NULL;
 	list_for_each_entry(tree, &tree_list, list) {
 		if (!strcmp(seed->pathname, tree->pathname)) {
 			put_tree(seed);
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2a9926275f80..a7c9e6ddb979 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1686,11 +1686,14 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
 		 */
 		cgroup_drop_root(opts.new_root);
 
-		if (((root->flags | opts.flags) & CGRP_ROOT_SANE_BEHAVIOR) &&
-		    root->flags != opts.flags) {
-			pr_err("cgroup: sane_behavior: new mount options should match the existing superblock\n");
-			ret = -EINVAL;
-			goto drop_new_super;
+		if (root->flags != opts.flags) {
+			if ((root->flags | opts.flags) & CGRP_ROOT_SANE_BEHAVIOR) {
+				pr_err("cgroup: sane_behavior: new mount options should match the existing superblock\n");
+				ret = -EINVAL;
+				goto drop_new_super;
+			} else {
+				pr_warning("cgroup: new mount options do not match the existing superblock, will be ignored\n");
+			}
 		}
 
 		/* no subsys rebinding, so refcounts don't change */
@@ -2699,13 +2702,14 @@ static int cgroup_add_file(struct cgroup *cgrp, struct cgroup_subsys *subsys,
 		goto out;
 	}
 
+	cfe->type = (void *)cft;
+	cfe->dentry = dentry;
+	dentry->d_fsdata = cfe;
+	simple_xattrs_init(&cfe->xattrs);
+
 	mode = cgroup_file_mode(cft);
 	error = cgroup_create_file(dentry, mode | S_IFREG, cgrp->root->sb);
 	if (!error) {
-		cfe->type = (void *)cft;
-		cfe->dentry = dentry;
-		dentry->d_fsdata = cfe;
-		simple_xattrs_init(&cfe->xattrs);
 		list_add_tail(&cfe->node, &parent->files);
 		cfe = NULL;
 	}
@@ -2953,11 +2957,8 @@ struct cgroup *cgroup_next_descendant_pre(struct cgroup *pos,
 	WARN_ON_ONCE(!rcu_read_lock_held());
 
 	/* if first iteration, pretend we just visited @cgroup */
-	if (!pos) {
-		if (list_empty(&cgroup->children))
-			return NULL;
+	if (!pos)
 		pos = cgroup;
-	}
 
 	/* visit the first child if exists */
 	next = list_first_or_null_rcu(&pos->children, struct cgroup, sibling);
@@ -2965,14 +2966,14 @@ struct cgroup *cgroup_next_descendant_pre(struct cgroup *pos,
 		return next;
 
 	/* no child, visit my or the closest ancestor's next sibling */
-	do {
+	while (pos != cgroup) {
 		next = list_entry_rcu(pos->sibling.next, struct cgroup,
 				      sibling);
 		if (&next->sibling != &pos->parent->children)
 			return next;
 
 		pos = pos->parent;
-	} while (pos != cgroup);
+	}
 
 	return NULL;
 }
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 66677003e223..383f8231e436 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -15,7 +15,6 @@
  */
 
 #include <linux/context_tracking.h>
-#include <linux/kvm_host.h>
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
 #include <linux/hardirq.h>
diff --git a/kernel/cpu.c b/kernel/cpu.c
index b5e4ab2d427e..198a38883e64 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -133,6 +133,27 @@ static void cpu_hotplug_done(void)
 	mutex_unlock(&cpu_hotplug.lock);
 }
 
+/*
+ * Wait for currently running CPU hotplug operations to complete (if any) and
+ * disable future CPU hotplug (from sysfs). The 'cpu_add_remove_lock' protects
+ * the 'cpu_hotplug_disabled' flag. The same lock is also acquired by the
+ * hotplug path before performing hotplug operations. So acquiring that lock
+ * guarantees mutual exclusion from any currently running hotplug operations.
+ */
+void cpu_hotplug_disable(void)
+{
+	cpu_maps_update_begin();
+	cpu_hotplug_disabled = 1;
+	cpu_maps_update_done();
+}
+
+void cpu_hotplug_enable(void)
+{
+	cpu_maps_update_begin();
+	cpu_hotplug_disabled = 0;
+	cpu_maps_update_done();
+}
+
 #else /* #if CONFIG_HOTPLUG_CPU */
 static void cpu_hotplug_begin(void) {}
 static void cpu_hotplug_done(void) {}
@@ -541,36 +562,6 @@ static int __init alloc_frozen_cpus(void)
 core_initcall(alloc_frozen_cpus);
 
 /*
- * Prevent regular CPU hotplug from racing with the freezer, by disabling CPU
- * hotplug when tasks are about to be frozen. Also, don't allow the freezer
- * to continue until any currently running CPU hotplug operation gets
- * completed.
- * To modify the 'cpu_hotplug_disabled' flag, we need to acquire the
- * 'cpu_add_remove_lock'. And this same lock is also taken by the regular
- * CPU hotplug path and released only after it is complete. Thus, we
- * (and hence the freezer) will block here until any currently running CPU
- * hotplug operation gets completed.
- */
-void cpu_hotplug_disable_before_freeze(void)
-{
-	cpu_maps_update_begin();
-	cpu_hotplug_disabled = 1;
-	cpu_maps_update_done();
-}
-
-
-/*
- * When tasks have been thawed, re-enable regular CPU hotplug (which had been
- * disabled while beginning to freeze tasks).
- */
-void cpu_hotplug_enable_after_thaw(void)
-{
-	cpu_maps_update_begin();
-	cpu_hotplug_disabled = 0;
-	cpu_maps_update_done();
-}
-
-/*
  * When callbacks for CPU hotplug notifications are being executed, we must
  * ensure that the state of the system with respect to the tasks being frozen
  * or not, as reported by the notification, remains unchanged *throughout the
@@ -589,12 +580,12 @@ cpu_hotplug_pm_callback(struct notifier_block *nb,
 
 	case PM_SUSPEND_PREPARE:
 	case PM_HIBERNATION_PREPARE:
-		cpu_hotplug_disable_before_freeze();
+		cpu_hotplug_disable();
 		break;
 
 	case PM_POST_SUSPEND:
 	case PM_POST_HIBERNATION:
-		cpu_hotplug_enable_after_thaw();
+		cpu_hotplug_enable();
 		break;
 
 	default:
diff --git a/kernel/cpu/idle.c b/kernel/cpu/idle.c
index d5585f5e038e..e695c0a0bcb5 100644
--- a/kernel/cpu/idle.c
+++ b/kernel/cpu/idle.c
@@ -5,6 +5,7 @@
 #include <linux/cpu.h>
 #include <linux/tick.h>
 #include <linux/mm.h>
+#include <linux/stackprotector.h>
 
 #include <asm/tlb.h>
 
@@ -58,6 +59,7 @@ void __weak arch_cpu_idle_dead(void) { }
 void __weak arch_cpu_idle(void)
 {
 	cpu_idle_force_poll = 1;
+	local_irq_enable();
 }
 
 /*
@@ -112,6 +114,21 @@ static void cpu_idle_loop(void)
 
 void cpu_startup_entry(enum cpuhp_state state)
 {
+	/*
+	 * This #ifdef needs to die, but it's too late in the cycle to
+	 * make this generic (arm and sh have never invoked the canary
+	 * init for the non boot cpus!). Will be fixed in 3.11
+	 */
+#ifdef CONFIG_X86
+	/*
+	 * If we're the non-boot CPU, nothing set the stack canary up
+	 * for us. The boot CPU already has it initialized but no harm
+	 * in doing it again. This is a good place for updating it, as
+	 * we wont ever return from this function (so the invalid
+	 * canaries already on the stack wont ever trigger).
+	 */
+	boot_init_stack_canary();
+#endif
 	current_set_polling();
 	arch_cpu_idle_prepare();
 	cpu_idle_loop();
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 9dc297faf7c0..b391907d5352 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -196,9 +196,6 @@ static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx,
 static void update_context_time(struct perf_event_context *ctx);
 static u64 perf_event_time(struct perf_event *event);
 
-static void ring_buffer_attach(struct perf_event *event,
-			       struct ring_buffer *rb);
-
 void __weak perf_event_print_debug(void)	{ }
 
 extern __weak const char *perf_pmu_name(void)
@@ -2918,6 +2915,7 @@ static void free_event_rcu(struct rcu_head *head)
 }
 
 static void ring_buffer_put(struct ring_buffer *rb);
+static void ring_buffer_detach(struct perf_event *event, struct ring_buffer *rb);
 
 static void free_event(struct perf_event *event)
 {
@@ -2942,15 +2940,30 @@ static void free_event(struct perf_event *event)
 		if (has_branch_stack(event)) {
 			static_key_slow_dec_deferred(&perf_sched_events);
 			/* is system-wide event */
-			if (!(event->attach_state & PERF_ATTACH_TASK))
+			if (!(event->attach_state & PERF_ATTACH_TASK)) {
 				atomic_dec(&per_cpu(perf_branch_stack_events,
 						    event->cpu));
+			}
 		}
 	}
 
 	if (event->rb) {
-		ring_buffer_put(event->rb);
-		event->rb = NULL;
+		struct ring_buffer *rb;
+
+		/*
+		 * Can happen when we close an event with re-directed output.
+		 *
+		 * Since we have a 0 refcount, perf_mmap_close() will skip
+		 * over us; possibly making our ring_buffer_put() the last.
+		 */
+		mutex_lock(&event->mmap_mutex);
+		rb = event->rb;
+		if (rb) {
+			rcu_assign_pointer(event->rb, NULL);
+			ring_buffer_detach(event, rb);
+			ring_buffer_put(rb); /* could be last */
+		}
+		mutex_unlock(&event->mmap_mutex);
 	}
 
 	if (is_cgroup_event(event))
@@ -3188,30 +3201,13 @@ static unsigned int perf_poll(struct file *file, poll_table *wait)
 	unsigned int events = POLL_HUP;
 
 	/*
-	 * Race between perf_event_set_output() and perf_poll(): perf_poll()
-	 * grabs the rb reference but perf_event_set_output() overrides it.
-	 * Here is the timeline for two threads T1, T2:
-	 * t0: T1, rb = rcu_dereference(event->rb)
-	 * t1: T2, old_rb = event->rb
-	 * t2: T2, event->rb = new rb
-	 * t3: T2, ring_buffer_detach(old_rb)
-	 * t4: T1, ring_buffer_attach(rb1)
-	 * t5: T1, poll_wait(event->waitq)
-	 *
-	 * To avoid this problem, we grab mmap_mutex in perf_poll()
-	 * thereby ensuring that the assignment of the new ring buffer
-	 * and the detachment of the old buffer appear atomic to perf_poll()
+	 * Pin the event->rb by taking event->mmap_mutex; otherwise
+	 * perf_event_set_output() can swizzle our rb and make us miss wakeups.
 	 */
 	mutex_lock(&event->mmap_mutex);
-
-	rcu_read_lock();
-	rb = rcu_dereference(event->rb);
-	if (rb) {
-		ring_buffer_attach(event, rb);
+	rb = event->rb;
+	if (rb)
 		events = atomic_xchg(&rb->poll, 0);
-	}
-	rcu_read_unlock();
-
 	mutex_unlock(&event->mmap_mutex);
 
 	poll_wait(file, &event->waitq, wait);
@@ -3521,16 +3517,12 @@ static void ring_buffer_attach(struct perf_event *event,
 		return;
 
 	spin_lock_irqsave(&rb->event_lock, flags);
-	if (!list_empty(&event->rb_entry))
-		goto unlock;
-
-	list_add(&event->rb_entry, &rb->event_list);
-unlock:
+	if (list_empty(&event->rb_entry))
+		list_add(&event->rb_entry, &rb->event_list);
 	spin_unlock_irqrestore(&rb->event_lock, flags);
 }
 
-static void ring_buffer_detach(struct perf_event *event,
-			       struct ring_buffer *rb)
+static void ring_buffer_detach(struct perf_event *event, struct ring_buffer *rb)
 {
 	unsigned long flags;
 
@@ -3549,13 +3541,10 @@ static void ring_buffer_wakeup(struct perf_event *event)
 
 	rcu_read_lock();
 	rb = rcu_dereference(event->rb);
-	if (!rb)
-		goto unlock;
-
-	list_for_each_entry_rcu(event, &rb->event_list, rb_entry)
-		wake_up_all(&event->waitq);
-
-unlock:
+	if (rb) {
+		list_for_each_entry_rcu(event, &rb->event_list, rb_entry)
+			wake_up_all(&event->waitq);
+	}
 	rcu_read_unlock();
 }
 
@@ -3584,18 +3573,10 @@ static struct ring_buffer *ring_buffer_get(struct perf_event *event)
 
 static void ring_buffer_put(struct ring_buffer *rb)
 {
-	struct perf_event *event, *n;
-	unsigned long flags;
-
 	if (!atomic_dec_and_test(&rb->refcount))
 		return;
 
-	spin_lock_irqsave(&rb->event_lock, flags);
-	list_for_each_entry_safe(event, n, &rb->event_list, rb_entry) {
-		list_del_init(&event->rb_entry);
-		wake_up_all(&event->waitq);
-	}
-	spin_unlock_irqrestore(&rb->event_lock, flags);
+	WARN_ON_ONCE(!list_empty(&rb->event_list));
 
 	call_rcu(&rb->rcu_head, rb_free_rcu);
 }
@@ -3605,26 +3586,100 @@ static void perf_mmap_open(struct vm_area_struct *vma)
 	struct perf_event *event = vma->vm_file->private_data;
 
 	atomic_inc(&event->mmap_count);
+	atomic_inc(&event->rb->mmap_count);
 }
 
+/*
+ * A buffer can be mmap()ed multiple times; either directly through the same
+ * event, or through other events by use of perf_event_set_output().
+ *
+ * In order to undo the VM accounting done by perf_mmap() we need to destroy
+ * the buffer here, where we still have a VM context. This means we need
+ * to detach all events redirecting to us.
+ */
 static void perf_mmap_close(struct vm_area_struct *vma)
 {
 	struct perf_event *event = vma->vm_file->private_data;
 
-	if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) {
-		unsigned long size = perf_data_size(event->rb);
-		struct user_struct *user = event->mmap_user;
-		struct ring_buffer *rb = event->rb;
+	struct ring_buffer *rb = event->rb;
+	struct user_struct *mmap_user = rb->mmap_user;
+	int mmap_locked = rb->mmap_locked;
+	unsigned long size = perf_data_size(rb);
+
+	atomic_dec(&rb->mmap_count);
+
+	if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex))
+		return;
 
-		atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm);
-		vma->vm_mm->pinned_vm -= event->mmap_locked;
-		rcu_assign_pointer(event->rb, NULL);
-		ring_buffer_detach(event, rb);
+	/* Detach current event from the buffer. */
+	rcu_assign_pointer(event->rb, NULL);
+	ring_buffer_detach(event, rb);
+	mutex_unlock(&event->mmap_mutex);
+
+	/* If there's still other mmap()s of this buffer, we're done. */
+	if (atomic_read(&rb->mmap_count)) {
+		ring_buffer_put(rb); /* can't be last */
+		return;
+	}
+
+	/*
+	 * No other mmap()s, detach from all other events that might redirect
+	 * into the now unreachable buffer. Somewhat complicated by the
+	 * fact that rb::event_lock otherwise nests inside mmap_mutex.
+	 */
+again:
+	rcu_read_lock();
+	list_for_each_entry_rcu(event, &rb->event_list, rb_entry) {
+		if (!atomic_long_inc_not_zero(&event->refcount)) {
+			/*
+			 * This event is en-route to free_event() which will
+			 * detach it and remove it from the list.
+			 */
+			continue;
+		}
+		rcu_read_unlock();
+
+		mutex_lock(&event->mmap_mutex);
+		/*
+		 * Check we didn't race with perf_event_set_output() which can
+		 * swizzle the rb from under us while we were waiting to
+		 * acquire mmap_mutex.
+		 *
+		 * If we find a different rb; ignore this event, a next
+		 * iteration will no longer find it on the list. We have to
+		 * still restart the iteration to make sure we're not now
+		 * iterating the wrong list.
+		 */
+		if (event->rb == rb) {
+			rcu_assign_pointer(event->rb, NULL);
+			ring_buffer_detach(event, rb);
+			ring_buffer_put(rb); /* can't be last, we still have one */
+		}
 		mutex_unlock(&event->mmap_mutex);
+		put_event(event);
 
-		ring_buffer_put(rb);
-		free_uid(user);
+		/*
+		 * Restart the iteration; either we're on the wrong list or
+		 * destroyed its integrity by doing a deletion.
+		 */
+		goto again;
 	}
+	rcu_read_unlock();
+
+	/*
+	 * It could be there's still a few 0-ref events on the list; they'll
+	 * get cleaned up by free_event() -- they'll also still have their
+	 * ref on the rb and will free it whenever they are done with it.
+	 *
+	 * Aside from that, this buffer is 'fully' detached and unmapped,
+	 * undo the VM accounting.
+	 */
+
+	atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm);
+	vma->vm_mm->pinned_vm -= mmap_locked;
+	free_uid(mmap_user);
+
+	ring_buffer_put(rb); /* could be last */
 }
 
 static const struct vm_operations_struct perf_mmap_vmops = {
@@ -3674,12 +3729,24 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	WARN_ON_ONCE(event->ctx->parent_ctx);
+again:
 	mutex_lock(&event->mmap_mutex);
 	if (event->rb) {
-		if (event->rb->nr_pages == nr_pages)
-			atomic_inc(&event->rb->refcount);
-		else
+		if (event->rb->nr_pages != nr_pages) {
 			ret = -EINVAL;
+			goto unlock;
+		}
+
+		if (!atomic_inc_not_zero(&event->rb->mmap_count)) {
+			/*
+			 * Raced against perf_mmap_close() through
+			 * perf_event_set_output(). Try again, hope for better
+			 * luck.
+			 */
+			mutex_unlock(&event->mmap_mutex);
+			goto again;
+		}
+
 		goto unlock;
 	}
 
@@ -3720,12 +3787,16 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
 		ret = -ENOMEM;
 		goto unlock;
 	}
-	rcu_assign_pointer(event->rb, rb);
+
+	atomic_set(&rb->mmap_count, 1);
+	rb->mmap_locked = extra;
+	rb->mmap_user = get_current_user();
 
 	atomic_long_add(user_extra, &user->locked_vm);
-	event->mmap_locked = extra;
-	event->mmap_user = get_current_user();
-	vma->vm_mm->pinned_vm += event->mmap_locked;
+	vma->vm_mm->pinned_vm += extra;
+
+	ring_buffer_attach(event, rb);
+	rcu_assign_pointer(event->rb, rb);
 
 	perf_event_update_userpage(event);
 
@@ -3734,7 +3805,11 @@ unlock:
 		atomic_inc(&event->mmap_count);
 	mutex_unlock(&event->mmap_mutex);
 
-	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
+	/*
+	 * Since pinned accounting is per vm we cannot allow fork() to copy our
+	 * vma.
+	 */
+	vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP;
 	vma->vm_ops = &perf_mmap_vmops;
 
 	return ret;
@@ -6412,6 +6487,8 @@ set:
 	if (atomic_read(&event->mmap_count))
 		goto unlock;
 
+	old_rb = event->rb;
+
 	if (output_event) {
 		/* get the rb we want to redirect to */
 		rb = ring_buffer_get(output_event);
@@ -6419,16 +6496,28 @@ set:
 			goto unlock;
 	}
 
-	old_rb = event->rb;
-	rcu_assign_pointer(event->rb, rb);
 	if (old_rb)
 		ring_buffer_detach(event, old_rb);
+
+	if (rb)
+		ring_buffer_attach(event, rb);
+
+	rcu_assign_pointer(event->rb, rb);
+
+	if (old_rb) {
+		ring_buffer_put(old_rb);
+		/*
+		 * Since we detached before setting the new rb, so that we
+		 * could attach the new rb, we could have missed a wakeup.
+		 * Provide it now.
+		 */
+		wake_up_all(&event->waitq);
+	}
+
 	ret = 0;
 unlock:
 	mutex_unlock(&event->mmap_mutex);
 
-	if (old_rb)
-		ring_buffer_put(old_rb);
 out:
 	return ret;
 }
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index a64f8aeb5c1f..20185ea64aa6 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -120,7 +120,7 @@ static int task_bp_pinned(int cpu, struct perf_event *bp, enum bp_type_idx type)
 	list_for_each_entry(iter, &bp_task_head, hw.bp_list) {
 		if (iter->hw.bp_target == tsk &&
 		    find_slot_idx(iter) == type &&
-		    cpu == iter->cpu)
+		    (iter->cpu < 0 || cpu == iter->cpu))
 			count += hw_breakpoint_weight(iter);
 	}
 
@@ -149,7 +149,7 @@ 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);
@@ -235,7 +235,7 @@ 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/events/internal.h b/kernel/events/internal.h
index eb675c4d59df..ca6599723be5 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -31,6 +31,10 @@ struct ring_buffer {
 	spinlock_t			event_lock;
 	struct list_head		event_list;
 
+	atomic_t			mmap_count;
+	unsigned long			mmap_locked;
+	struct user_struct		*mmap_user;
+
 	struct perf_event_mmap_page	*user_page;
 	void				*data_pages[0];
 };
diff --git a/kernel/exit.c b/kernel/exit.c
index af2eb3cbd499..7bb73f9d09db 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -649,7 +649,6 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
 	 *	jobs, send them a SIGHUP and then a SIGCONT.  (POSIX 3.2.2.2)
 	 */
 	forget_original_parent(tsk);
-	exit_task_namespaces(tsk);
 
 	write_lock_irq(&tasklist_lock);
 	if (group_dead)
@@ -795,6 +794,7 @@ void do_exit(long code)
 	exit_shm(tsk);
 	exit_files(tsk);
 	exit_fs(tsk);
+	exit_task_namespaces(tsk);
 	exit_task_work(tsk);
 	check_stack_usage();
 	exit_thread();
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 5a83dde8ca0c..54a4d5223238 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -143,7 +143,10 @@ static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain,
  * irq_domain_add_simple() - Allocate and register a simple irq_domain.
  * @of_node: pointer to interrupt controller's device tree node.
  * @size: total number of irqs in mapping
- * @first_irq: first number of irq block assigned to the domain
+ * @first_irq: first number of irq block assigned to the domain,
+ *	pass zero to assign irqs on-the-fly. This will result in a
+ *	linear IRQ domain so it is important to use irq_create_mapping()
+ *	for each used IRQ, especially when SPARSE_IRQ is enabled.
  * @ops: map/unmap domain callbacks
  * @host_data: Controller private data pointer
  *
@@ -191,6 +194,7 @@ struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
 	/* A linear domain is the default */
 	return irq_domain_add_linear(of_node, size, ops, host_data);
 }
+EXPORT_SYMBOL_GPL(irq_domain_add_simple);
 
 /**
  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
@@ -397,11 +401,12 @@ static void irq_domain_disassociate_many(struct irq_domain *domain,
 	while (count--) {
 		int irq = irq_base + count;
 		struct irq_data *irq_data = irq_get_irq_data(irq);
-		irq_hw_number_t hwirq = irq_data->hwirq;
+		irq_hw_number_t hwirq;
 
 		if (WARN_ON(!irq_data || irq_data->domain != domain))
 			continue;
 
+		hwirq = irq_data->hwirq;
 		irq_set_status_flags(irq, IRQ_NOREQUEST);
 
 		/* remove chip and handler */
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 3fed7f0cbcdf..bddf3b201a48 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -467,6 +467,7 @@ static struct kprobe *__kprobes get_optimized_kprobe(unsigned long addr)
 /* Optimization staging list, protected by kprobe_mutex */
 static LIST_HEAD(optimizing_list);
 static LIST_HEAD(unoptimizing_list);
+static LIST_HEAD(freeing_list);
 
 static void kprobe_optimizer(struct work_struct *work);
 static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer);
@@ -504,7 +505,7 @@ static __kprobes void do_optimize_kprobes(void)
  * Unoptimize (replace a jump with a breakpoint and remove the breakpoint
  * if need) kprobes listed on unoptimizing_list.
  */
-static __kprobes void do_unoptimize_kprobes(struct list_head *free_list)
+static __kprobes void do_unoptimize_kprobes(void)
 {
 	struct optimized_kprobe *op, *tmp;
 
@@ -515,9 +516,9 @@ static __kprobes void do_unoptimize_kprobes(struct list_head *free_list)
 	/* Ditto to do_optimize_kprobes */
 	get_online_cpus();
 	mutex_lock(&text_mutex);
-	arch_unoptimize_kprobes(&unoptimizing_list, free_list);
+	arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list);
 	/* Loop free_list for disarming */
-	list_for_each_entry_safe(op, tmp, free_list, list) {
+	list_for_each_entry_safe(op, tmp, &freeing_list, list) {
 		/* Disarm probes if marked disabled */
 		if (kprobe_disabled(&op->kp))
 			arch_disarm_kprobe(&op->kp);
@@ -536,11 +537,11 @@ static __kprobes void do_unoptimize_kprobes(struct list_head *free_list)
 }
 
 /* Reclaim all kprobes on the free_list */
-static __kprobes void do_free_cleaned_kprobes(struct list_head *free_list)
+static __kprobes void do_free_cleaned_kprobes(void)
 {
 	struct optimized_kprobe *op, *tmp;
 
-	list_for_each_entry_safe(op, tmp, free_list, list) {
+	list_for_each_entry_safe(op, tmp, &freeing_list, list) {
 		BUG_ON(!kprobe_unused(&op->kp));
 		list_del_init(&op->list);
 		free_aggr_kprobe(&op->kp);
@@ -556,8 +557,6 @@ static __kprobes void kick_kprobe_optimizer(void)
 /* Kprobe jump optimizer */
 static __kprobes void kprobe_optimizer(struct work_struct *work)
 {
-	LIST_HEAD(free_list);
-
 	mutex_lock(&kprobe_mutex);
 	/* Lock modules while optimizing kprobes */
 	mutex_lock(&module_mutex);
@@ -566,7 +565,7 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
 	 * Step 1: Unoptimize kprobes and collect cleaned (unused and disarmed)
 	 * kprobes before waiting for quiesence period.
 	 */
-	do_unoptimize_kprobes(&free_list);
+	do_unoptimize_kprobes();
 
 	/*
 	 * Step 2: Wait for quiesence period to ensure all running interrupts
@@ -581,7 +580,7 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
 	do_optimize_kprobes();
 
 	/* Step 4: Free cleaned kprobes after quiesence period */
-	do_free_cleaned_kprobes(&free_list);
+	do_free_cleaned_kprobes();
 
 	mutex_unlock(&module_mutex);
 	mutex_unlock(&kprobe_mutex);
@@ -723,8 +722,19 @@ static void __kprobes kill_optimized_kprobe(struct kprobe *p)
 	if (!list_empty(&op->list))
 		/* Dequeue from the (un)optimization queue */
 		list_del_init(&op->list);
-
 	op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
+
+	if (kprobe_unused(p)) {
+		/* Enqueue if it is unused */
+		list_add(&op->list, &freeing_list);
+		/*
+		 * Remove unused probes from the hash list. After waiting
+		 * for synchronization, this probe is reclaimed.
+		 * (reclaiming is done by do_free_cleaned_kprobes().)
+		 */
+		hlist_del_rcu(&op->kp.hlist);
+	}
+
 	/* Don't touch the code, because it is already freed. */
 	arch_remove_optimized_kprobe(op);
 }
diff --git a/kernel/printk.c b/kernel/printk.c
index fa36e1494420..8212c1aef125 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -363,6 +363,53 @@ static void log_store(int facility, int level,
 	log_next_seq++;
 }
 
+#ifdef CONFIG_SECURITY_DMESG_RESTRICT
+int dmesg_restrict = 1;
+#else
+int dmesg_restrict;
+#endif
+
+static int syslog_action_restricted(int type)
+{
+	if (dmesg_restrict)
+		return 1;
+	/*
+	 * Unless restricted, we allow "read all" and "get buffer size"
+	 * for everybody.
+	 */
+	return type != SYSLOG_ACTION_READ_ALL &&
+	       type != SYSLOG_ACTION_SIZE_BUFFER;
+}
+
+static int check_syslog_permissions(int type, bool from_file)
+{
+	/*
+	 * If this is from /proc/kmsg and we've already opened it, then we've
+	 * already done the capabilities checks at open time.
+	 */
+	if (from_file && type != SYSLOG_ACTION_OPEN)
+		return 0;
+
+	if (syslog_action_restricted(type)) {
+		if (capable(CAP_SYSLOG))
+			return 0;
+		/*
+		 * For historical reasons, accept CAP_SYS_ADMIN too, with
+		 * a warning.
+		 */
+		if (capable(CAP_SYS_ADMIN)) {
+			pr_warn_once("%s (%d): Attempt to access syslog with "
+				     "CAP_SYS_ADMIN but no CAP_SYSLOG "
+				     "(deprecated).\n",
+				 current->comm, task_pid_nr(current));
+			return 0;
+		}
+		return -EPERM;
+	}
+	return security_syslog(type);
+}
+
+
 /* /dev/kmsg - userspace message inject/listen interface */
 struct devkmsg_user {
 	u64 seq;
@@ -620,7 +667,8 @@ static int devkmsg_open(struct inode *inode, struct file *file)
 	if ((file->f_flags & O_ACCMODE) == O_WRONLY)
 		return 0;
 
-	err = security_syslog(SYSLOG_ACTION_READ_ALL);
+	err = check_syslog_permissions(SYSLOG_ACTION_READ_ALL,
+				       SYSLOG_FROM_READER);
 	if (err)
 		return err;
 
@@ -813,45 +861,6 @@ static inline void boot_delay_msec(int level)
 }
 #endif
 
-#ifdef CONFIG_SECURITY_DMESG_RESTRICT
-int dmesg_restrict = 1;
-#else
-int dmesg_restrict;
-#endif
-
-static int syslog_action_restricted(int type)
-{
-	if (dmesg_restrict)
-		return 1;
-	/* Unless restricted, we allow "read all" and "get buffer size" for everybody */
-	return type != SYSLOG_ACTION_READ_ALL && type != SYSLOG_ACTION_SIZE_BUFFER;
-}
-
-static int check_syslog_permissions(int type, bool from_file)
-{
-	/*
-	 * If this is from /proc/kmsg and we've already opened it, then we've
-	 * already done the capabilities checks at open time.
-	 */
-	if (from_file && type != SYSLOG_ACTION_OPEN)
-		return 0;
-
-	if (syslog_action_restricted(type)) {
-		if (capable(CAP_SYSLOG))
-			return 0;
-		/* For historical reasons, accept CAP_SYS_ADMIN too, with a warning */
-		if (capable(CAP_SYS_ADMIN)) {
-			printk_once(KERN_WARNING "%s (%d): "
-				 "Attempt to access syslog with CAP_SYS_ADMIN "
-				 "but no CAP_SYSLOG (deprecated).\n",
-				 current->comm, task_pid_nr(current));
-			return 0;
-		}
-		return -EPERM;
-	}
-	return 0;
-}
-
 #if defined(CONFIG_PRINTK_TIME)
 static bool printk_time = 1;
 #else
@@ -1249,7 +1258,7 @@ out:
 
 SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
 {
-	return do_syslog(type, buf, len, SYSLOG_FROM_CALL);
+	return do_syslog(type, buf, len, SYSLOG_FROM_READER);
 }
 
 /*
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index aed981a3f69c..335a7ae697f5 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -665,20 +665,22 @@ static int ptrace_peek_siginfo(struct task_struct *child,
 		if (unlikely(is_compat_task())) {
 			compat_siginfo_t __user *uinfo = compat_ptr(data);
 
-			ret = copy_siginfo_to_user32(uinfo, &info);
-			ret |= __put_user(info.si_code, &uinfo->si_code);
+			if (copy_siginfo_to_user32(uinfo, &info) ||
+			    __put_user(info.si_code, &uinfo->si_code)) {
+				ret = -EFAULT;
+				break;
+			}
+
 		} else
 #endif
 		{
 			siginfo_t __user *uinfo = (siginfo_t __user *) data;
 
-			ret = copy_siginfo_to_user(uinfo, &info);
-			ret |= __put_user(info.si_code, &uinfo->si_code);
-		}
-
-		if (ret) {
-			ret = -EFAULT;
-			break;
+			if (copy_siginfo_to_user(uinfo, &info) ||
+			    __put_user(info.si_code, &uinfo->si_code)) {
+				ret = -EFAULT;
+				break;
+			}
 		}
 
 		data += sizeof(siginfo_t);
diff --git a/kernel/range.c b/kernel/range.c
index 071b0ab455cb..322ea8e93e4b 100644
--- a/kernel/range.c
+++ b/kernel/range.c
@@ -4,7 +4,7 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/sort.h>
-
+#include <linux/string.h>
 #include <linux/range.h>
 
 int add_range(struct range *range, int az, int nr_range, u64 start, u64 end)
@@ -32,9 +32,8 @@ int add_range_with_merge(struct range *range, int az, int nr_range,
 	if (start >= end)
 		return nr_range;
 
-	/* Try to merge it with old one: */
+	/* get new start/end: */
 	for (i = 0; i < nr_range; i++) {
-		u64 final_start, final_end;
 		u64 common_start, common_end;
 
 		if (!range[i].end)
@@ -45,12 +44,16 @@ int add_range_with_merge(struct range *range, int az, int nr_range,
 		if (common_start > common_end)
 			continue;
 
-		final_start = min(range[i].start, start);
-		final_end = max(range[i].end, end);
+		/* new start/end, will add it back at last */
+		start = min(range[i].start, start);
+		end = max(range[i].end, end);
 
-		range[i].start = final_start;
-		range[i].end =  final_end;
-		return nr_range;
+		memmove(&range[i], &range[i + 1],
+			(nr_range - (i + 1)) * sizeof(range[i]));
+		range[nr_range - 1].start = 0;
+		range[nr_range - 1].end   = 0;
+		nr_range--;
+		i--;
 	}
 
 	/* Need to add it: */
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 16ea67925015..35380019f0fc 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -1451,9 +1451,9 @@ static int rcu_gp_init(struct rcu_state *rsp)
 					    rnp->grphi, rnp->qsmask);
 		raw_spin_unlock_irq(&rnp->lock);
 #ifdef CONFIG_PROVE_RCU_DELAY
-		if ((prandom_u32() % (rcu_num_nodes * 8)) == 0 &&
+		if ((prandom_u32() % (rcu_num_nodes + 1)) == 0 &&
 		    system_state == SYSTEM_RUNNING)
-			schedule_timeout_uninterruptible(2);
+			udelay(200);
 #endif /* #ifdef CONFIG_PROVE_RCU_DELAY */
 		cond_resched();
 	}
@@ -1613,6 +1613,14 @@ static int __noreturn rcu_gp_kthread(void *arg)
 	}
 }
 
+static void rsp_wakeup(struct irq_work *work)
+{
+	struct rcu_state *rsp = container_of(work, struct rcu_state, wakeup_work);
+
+	/* Wake up rcu_gp_kthread() to start the grace period. */
+	wake_up(&rsp->gp_wq);
+}
+
 /*
  * Start a new RCU grace period if warranted, re-initializing the hierarchy
  * in preparation for detecting the next grace period.  The caller must hold
@@ -1637,8 +1645,12 @@ rcu_start_gp_advanced(struct rcu_state *rsp, struct rcu_node *rnp,
 	}
 	rsp->gp_flags = RCU_GP_FLAG_INIT;
 
-	/* Wake up rcu_gp_kthread() to start the grace period. */
-	wake_up(&rsp->gp_wq);
+	/*
+	 * We can't do wakeups while holding the rnp->lock, as that
+	 * could cause possible deadlocks with the rq->lock. Deter
+	 * the wakeup to interrupt context.
+	 */
+	irq_work_queue(&rsp->wakeup_work);
 }
 
 /*
@@ -3235,6 +3247,7 @@ static void __init rcu_init_one(struct rcu_state *rsp,
 
 	rsp->rda = rda;
 	init_waitqueue_head(&rsp->gp_wq);
+	init_irq_work(&rsp->wakeup_work, rsp_wakeup);
 	rnp = rsp->level[rcu_num_lvls - 1];
 	for_each_possible_cpu(i) {
 		while (i > rnp->grphi)
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index da77a8f57ff9..4df503470e42 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -27,6 +27,7 @@
 #include <linux/threads.h>
 #include <linux/cpumask.h>
 #include <linux/seqlock.h>
+#include <linux/irq_work.h>
 
 /*
  * Define shape of hierarchy based on NR_CPUS, CONFIG_RCU_FANOUT, and
@@ -442,6 +443,7 @@ struct rcu_state {
 	char *name;				/* Name of structure. */
 	char abbr;				/* Abbreviated name. */
 	struct list_head flavors;		/* List of RCU flavors. */
+	struct irq_work wakeup_work;		/* Postponed wakeups */
 };
 
 /* Values for rcu_state structure's gp_flags field. */
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 08746cc12370..9b1f2e533b95 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4184,7 +4184,7 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
 	 */
 	idle->sched_class = &idle_sched_class;
 	ftrace_graph_init_idle_task(idle, cpu);
-	vtime_init_idle(idle);
+	vtime_init_idle(idle, cpu);
 #if defined(CONFIG_SMP)
 	sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu);
 #endif
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 94691bcd7364..a7959e05a9d5 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -746,17 +746,17 @@ void arch_vtime_task_switch(struct task_struct *prev)
 
 	write_seqlock(&current->vtime_seqlock);
 	current->vtime_snap_whence = VTIME_SYS;
-	current->vtime_snap = sched_clock();
+	current->vtime_snap = sched_clock_cpu(smp_processor_id());
 	write_sequnlock(&current->vtime_seqlock);
 }
 
-void vtime_init_idle(struct task_struct *t)
+void vtime_init_idle(struct task_struct *t, int cpu)
 {
 	unsigned long flags;
 
 	write_seqlock_irqsave(&t->vtime_seqlock, flags);
 	t->vtime_snap_whence = VTIME_SYS;
-	t->vtime_snap = sched_clock();
+	t->vtime_snap = sched_clock_cpu(cpu);
 	write_sequnlock_irqrestore(&t->vtime_seqlock, flags);
 }
 
diff --git a/kernel/softirq.c b/kernel/softirq.c
index b5197dcb0dad..3d6833f125d3 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -195,8 +195,12 @@ void local_bh_enable_ip(unsigned long ip)
 EXPORT_SYMBOL(local_bh_enable_ip);
 
 /*
- * We restart softirq processing for at most 2 ms,
- * and if need_resched() is not set.
+ * We restart softirq processing for at most MAX_SOFTIRQ_RESTART times,
+ * but break the loop if need_resched() is set or after 2 ms.
+ * The MAX_SOFTIRQ_TIME provides a nice upper bound in most cases, but in
+ * certain cases, such as stop_machine(), jiffies may cease to
+ * increment and so we need the MAX_SOFTIRQ_RESTART limit as
+ * well to make sure we eventually return from this method.
  *
  * These limits have been established via experimentation.
  * The two things to balance is latency against fairness -
@@ -204,6 +208,7 @@ EXPORT_SYMBOL(local_bh_enable_ip);
  * should not be able to lock up the box.
  */
 #define MAX_SOFTIRQ_TIME  msecs_to_jiffies(2)
+#define MAX_SOFTIRQ_RESTART 10
 
 asmlinkage void __do_softirq(void)
 {
@@ -212,6 +217,7 @@ asmlinkage void __do_softirq(void)
 	unsigned long end = jiffies + MAX_SOFTIRQ_TIME;
 	int cpu;
 	unsigned long old_flags = current->flags;
+	int max_restart = MAX_SOFTIRQ_RESTART;
 
 	/*
 	 * Mask out PF_MEMALLOC s current task context is borrowed for the
@@ -265,7 +271,8 @@ restart:
 
 	pending = local_softirq_pending();
 	if (pending) {
-		if (time_before(jiffies, end) && !need_resched())
+		if (time_before(jiffies, end) && !need_resched() &&
+		    --max_restart)
 			goto restart;
 
 		wakeup_softirqd();
diff --git a/kernel/sys.c b/kernel/sys.c
index b95d3c72ba21..2bbd9a73b54c 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -362,6 +362,29 @@ int unregister_reboot_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL(unregister_reboot_notifier);
 
+/* Add backwards compatibility for stable trees. */
+#ifndef PF_NO_SETAFFINITY
+#define PF_NO_SETAFFINITY		PF_THREAD_BOUND
+#endif
+
+static void migrate_to_reboot_cpu(void)
+{
+	/* The boot cpu is always logical cpu 0 */
+	int cpu = 0;
+
+	cpu_hotplug_disable();
+
+	/* Make certain the cpu I'm about to reboot on is online */
+	if (!cpu_online(cpu))
+		cpu = cpumask_first(cpu_online_mask);
+
+	/* Prevent races with other tasks migrating this task */
+	current->flags |= PF_NO_SETAFFINITY;
+
+	/* Make certain I only run on the appropriate processor */
+	set_cpus_allowed_ptr(current, cpumask_of(cpu));
+}
+
 /**
  *	kernel_restart - reboot the system
  *	@cmd: pointer to buffer containing command to execute for restart
@@ -373,7 +396,7 @@ EXPORT_SYMBOL(unregister_reboot_notifier);
 void kernel_restart(char *cmd)
 {
 	kernel_restart_prepare(cmd);
-	disable_nonboot_cpus();
+	migrate_to_reboot_cpu();
 	syscore_shutdown();
 	if (!cmd)
 		printk(KERN_EMERG "Restarting system.\n");
@@ -400,7 +423,7 @@ static void kernel_shutdown_prepare(enum system_states state)
 void kernel_halt(void)
 {
 	kernel_shutdown_prepare(SYSTEM_HALT);
-	disable_nonboot_cpus();
+	migrate_to_reboot_cpu();
 	syscore_shutdown();
 	printk(KERN_EMERG "System halted.\n");
 	kmsg_dump(KMSG_DUMP_HALT);
@@ -419,7 +442,7 @@ void kernel_power_off(void)
 	kernel_shutdown_prepare(SYSTEM_POWER_OFF);
 	if (pm_power_off_prepare)
 		pm_power_off_prepare();
-	disable_nonboot_cpus();
+	migrate_to_reboot_cpu();
 	syscore_shutdown();
 	printk(KERN_EMERG "Power down.\n");
 	kmsg_dump(KMSG_DUMP_POWEROFF);
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 12ff13a838c6..8f5b3b98577b 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -874,7 +874,6 @@ static void hardpps_update_phase(long error)
 void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
 {
 	struct pps_normtime pts_norm, freq_norm;
-	unsigned long flags;
 
 	pts_norm = pps_normalize_ts(*phase_ts);
 
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 24938d577669..20d6fba70652 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -511,6 +511,12 @@ again:
 		}
 	}
 
+	/*
+	 * Remove the current cpu from the pending mask. The event is
+	 * delivered immediately in tick_do_broadcast() !
+	 */
+	cpumask_clear_cpu(smp_processor_id(), tick_broadcast_pending_mask);
+
 	/* Take care of enforced broadcast requests */
 	cpumask_or(tmpmask, tmpmask, tick_broadcast_force_mask);
 	cpumask_clear(tick_broadcast_force_mask);
@@ -575,8 +581,8 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 
 	raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
 	if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) {
-		WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask));
 		if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_oneshot_mask)) {
+			WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask));
 			clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
 			/*
 			 * We only reprogram the broadcast timer if we
@@ -593,8 +599,6 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 	} else {
 		if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_oneshot_mask)) {
 			clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT);
-			if (dev->next_event.tv64 == KTIME_MAX)
-				goto out;
 			/*
 			 * The cpu which was handling the broadcast
 			 * timer marked this cpu in the broadcast
@@ -609,6 +613,11 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 				goto out;
 
 			/*
+			 * Bail out if there is no next event.
+			 */
+			if (dev->next_event.tv64 == KTIME_MAX)
+				goto out;
+			/*
 			 * If the pending bit is not set, then we are
 			 * either the CPU handling the broadcast
 			 * interrupt or we got woken by something else.
@@ -692,10 +701,6 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
 
 		bc->event_handler = tick_handle_oneshot_broadcast;
 
-		/* Take the do_timer update */
-		if (!tick_nohz_full_cpu(cpu))
-			tick_do_timer_cpu = cpu;
-
 		/*
 		 * We must be careful here. There might be other CPUs
 		 * waiting for periodic broadcast. We need to set the
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index f4208138fbf4..0cf1c1453181 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -306,7 +306,7 @@ static int __cpuinit tick_nohz_cpu_down_callback(struct notifier_block *nfb,
 		 * we can't safely shutdown that CPU.
 		 */
 		if (have_nohz_full_mask && tick_do_timer_cpu == cpu)
-			return -EINVAL;
+			return NOTIFY_BAD;
 		break;
 	}
 	return NOTIFY_OK;
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 98cd470bbe49..baeeb5c87cf1 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -975,6 +975,14 @@ static int timekeeping_suspend(void)
 
 	read_persistent_clock(&timekeeping_suspend_time);
 
+	/*
+	 * On some systems the persistent_clock can not be detected at
+	 * timekeeping_init by its return value, so if we see a valid
+	 * value returned, update the persistent_clock_exists flag.
+	 */
+	if (timekeeping_suspend_time.tv_sec || timekeeping_suspend_time.tv_nsec)
+		persistent_clock_exist = true;
+
 	raw_spin_lock_irqsave(&timekeeper_lock, flags);
 	write_seqcount_begin(&timekeeper_seq);
 	timekeeping_forward_now(tk);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b549b0f5b977..6c508ff33c62 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -120,22 +120,22 @@ static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip);
 
 /*
  * Traverse the ftrace_global_list, invoking all entries.  The reason that we
- * can use rcu_dereference_raw() is that elements removed from this list
+ * can use rcu_dereference_raw_notrace() is that elements removed from this list
  * are simply leaked, so there is no need to interact with a grace-period
- * mechanism.  The rcu_dereference_raw() calls are needed to handle
+ * mechanism.  The rcu_dereference_raw_notrace() calls are needed to handle
  * concurrent insertions into the ftrace_global_list.
  *
  * Silly Alpha and silly pointer-speculation compiler optimizations!
  */
 #define do_for_each_ftrace_op(op, list)			\
-	op = rcu_dereference_raw(list);			\
+	op = rcu_dereference_raw_notrace(list);			\
 	do
 
 /*
  * Optimized for just a single item in the list (as that is the normal case).
  */
 #define while_for_each_ftrace_op(op)				\
-	while (likely(op = rcu_dereference_raw((op)->next)) &&	\
+	while (likely(op = rcu_dereference_raw_notrace((op)->next)) &&	\
 	       unlikely((op) != &ftrace_list_end))
 
 static inline void ftrace_ops_init(struct ftrace_ops *ops)
@@ -779,7 +779,7 @@ ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip)
 	if (hlist_empty(hhd))
 		return NULL;
 
-	hlist_for_each_entry_rcu(rec, hhd, node) {
+	hlist_for_each_entry_rcu_notrace(rec, hhd, node) {
 		if (rec->ip == ip)
 			return rec;
 	}
@@ -1165,7 +1165,7 @@ ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip)
 
 	hhd = &hash->buckets[key];
 
-	hlist_for_each_entry_rcu(entry, hhd, hlist) {
+	hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) {
 		if (entry->ip == ip)
 			return entry;
 	}
@@ -1422,8 +1422,8 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip)
 	struct ftrace_hash *notrace_hash;
 	int ret;
 
-	filter_hash = rcu_dereference_raw(ops->filter_hash);
-	notrace_hash = rcu_dereference_raw(ops->notrace_hash);
+	filter_hash = rcu_dereference_raw_notrace(ops->filter_hash);
+	notrace_hash = rcu_dereference_raw_notrace(ops->notrace_hash);
 
 	if ((ftrace_hash_empty(filter_hash) ||
 	     ftrace_lookup_ip(filter_hash, ip)) &&
@@ -2920,7 +2920,7 @@ static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
 	 * on the hash. rcu_read_lock is too dangerous here.
 	 */
 	preempt_disable_notrace();
-	hlist_for_each_entry_rcu(entry, hhd, node) {
+	hlist_for_each_entry_rcu_notrace(entry, hhd, node) {
 		if (entry->ip == ip)
 			entry->ops->func(ip, parent_ip, &entry->data);
 	}
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4d79485b3237..e71a8be4a6ee 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -652,8 +652,6 @@ static struct {
 	ARCH_TRACE_CLOCKS
 };
 
-int trace_clock_id;
-
 /*
  * trace_parser_get_init - gets the buffer for trace parser
  */
@@ -843,7 +841,15 @@ __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;
@@ -2818,7 +2824,7 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
 		iter->iter_flags |= TRACE_FILE_ANNOTATE;
 
 	/* Output in nanoseconds only if we are using a clock in nanoseconds. */
-	if (trace_clocks[trace_clock_id].in_ns)
+	if (trace_clocks[tr->clock_id].in_ns)
 		iter->iter_flags |= TRACE_FILE_TIME_IN_NS;
 
 	/* stop the trace while dumping if we are not opening "snapshot" */
@@ -3817,7 +3823,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
 		iter->iter_flags |= TRACE_FILE_LAT_FMT;
 
 	/* Output in nanoseconds only if we are using a clock in nanoseconds. */
-	if (trace_clocks[trace_clock_id].in_ns)
+	if (trace_clocks[tr->clock_id].in_ns)
 		iter->iter_flags |= TRACE_FILE_TIME_IN_NS;
 
 	iter->cpu_file = tc->cpu;
@@ -5087,7 +5093,7 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
 	cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu);
 	trace_seq_printf(s, "bytes: %ld\n", cnt);
 
-	if (trace_clocks[trace_clock_id].in_ns) {
+	if (trace_clocks[tr->clock_id].in_ns) {
 		/* local or global for trace_clock */
 		t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu));
 		usec_rem = do_div(t, USEC_PER_SEC);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 711ca7d3e7f1..20572ed88c5c 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -700,8 +700,6 @@ enum print_line_t print_trace_line(struct trace_iterator *iter);
 
 extern unsigned long trace_flags;
 
-extern int trace_clock_id;
-
 /* Standard output formatting function used for function return traces */
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 55e2cf66967b..2901e3b88590 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -1159,7 +1159,7 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
 	/* stop the tracing. */
 	tracing_stop();
 	/* check the trace buffer */
-	ret = trace_test_buffer(tr, &count);
+	ret = trace_test_buffer(&tr->trace_buffer, &count);
 	trace->reset(tr);
 	tracing_start();