Merge branch 'fixes-v3.0-rc3' into devel-fixes

12 files changed, 113 insertions, 65 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index d863b3c057bb..9efe7108ccaf 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7402,26 +7402,12 @@ static int __perf_cgroup_move(void *info)
 	return 0;
 }
 
-static void perf_cgroup_move(struct task_struct *task)
+static void
+perf_cgroup_attach_task(struct cgroup *cgrp, struct task_struct *task)
 {
 	task_function_call(task, __perf_cgroup_move, task);
 }
 
-static void perf_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
-		struct cgroup *old_cgrp, struct task_struct *task,
-		bool threadgroup)
-{
-	perf_cgroup_move(task);
-	if (threadgroup) {
-		struct task_struct *c;
-		rcu_read_lock();
-		list_for_each_entry_rcu(c, &task->thread_group, thread_group) {
-			perf_cgroup_move(c);
-		}
-		rcu_read_unlock();
-	}
-}
-
 static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
 		struct cgroup *old_cgrp, struct task_struct *task)
 {
@@ -7433,7 +7419,7 @@ static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
 	if (!(task->flags & PF_EXITING))
 		return;
 
-	perf_cgroup_move(task);
+	perf_cgroup_attach_task(cgrp, task);
 }
 
 struct cgroup_subsys perf_subsys = {
@@ -7442,6 +7428,6 @@ struct cgroup_subsys perf_subsys = {
 	.create		= perf_cgroup_create,
 	.destroy	= perf_cgroup_destroy,
 	.exit		= perf_cgroup_exit,
-	.attach		= perf_cgroup_attach,
+	.attach_task	= perf_cgroup_attach_task,
 };
 #endif /* CONFIG_CGROUP_PERF */
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 90cb55f6d7eb..470d08c82bbe 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -133,12 +133,6 @@ handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
 		switch (res) {
 		case IRQ_WAKE_THREAD:
 			/*
-			 * Set result to handled so the spurious check
-			 * does not trigger.
-			 */
-			res = IRQ_HANDLED;
-
-			/*
 			 * Catch drivers which return WAKE_THREAD but
 			 * did not set up a thread function
 			 */
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 886e80347b32..4c60a50e66b2 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -257,13 +257,11 @@ int __init early_irq_init(void)
 	count = ARRAY_SIZE(irq_desc);
 
 	for (i = 0; i < count; i++) {
-		desc[i].irq_data.irq = i;
-		desc[i].irq_data.chip = &no_irq_chip;
 		desc[i].kstat_irqs = alloc_percpu(unsigned int);
-		irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
-		alloc_masks(desc + i, GFP_KERNEL, node);
-		desc_smp_init(desc + i, node);
+		alloc_masks(&desc[i], GFP_KERNEL, node);
+		raw_spin_lock_init(&desc[i].lock);
 		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
+		desc_set_defaults(i, &desc[i], node);
 	}
 	return arch_early_irq_init();
 }
@@ -346,6 +344,12 @@ irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node)
 	if (!cnt)
 		return -EINVAL;
 
+	if (irq >= 0) {
+		if (from > irq)
+			return -EINVAL;
+		from = irq;
+	}
+
 	mutex_lock(&sparse_irq_lock);
 
 	start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index f7ce0021e1c4..0a7840aeb0fb 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -491,6 +491,9 @@ int irq_set_irq_wake(unsigned int irq, unsigned int on)
 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags);
 	int ret = 0;
 
+	if (!desc)
+		return -EINVAL;
+
 	/* wakeup-capable irqs can be shared between drivers that
 	 * don't need to have the same sleep mode behaviors.
 	 */
@@ -723,13 +726,16 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
  * context. So we need to disable bh here to avoid deadlocks and other
  * side effects.
  */
-static void
+static irqreturn_t
 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
 {
+	irqreturn_t ret;
+
 	local_bh_disable();
-	action->thread_fn(action->irq, action->dev_id);
+	ret = action->thread_fn(action->irq, action->dev_id);
 	irq_finalize_oneshot(desc, action, false);
 	local_bh_enable();
+	return ret;
 }
 
 /*
@@ -737,10 +743,14 @@ irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
  * preemtible - many of them need to sleep and wait for slow busses to
  * complete.
  */
-static void irq_thread_fn(struct irq_desc *desc, struct irqaction *action)
+static irqreturn_t irq_thread_fn(struct irq_desc *desc,
+		struct irqaction *action)
 {
-	action->thread_fn(action->irq, action->dev_id);
+	irqreturn_t ret;
+
+	ret = action->thread_fn(action->irq, action->dev_id);
 	irq_finalize_oneshot(desc, action, false);
+	return ret;
 }
 
 /*
@@ -753,7 +763,8 @@ static int irq_thread(void *data)
 	};
 	struct irqaction *action = data;
 	struct irq_desc *desc = irq_to_desc(action->irq);
-	void (*handler_fn)(struct irq_desc *desc, struct irqaction *action);
+	irqreturn_t (*handler_fn)(struct irq_desc *desc,
+			struct irqaction *action);
 	int wake;
 
 	if (force_irqthreads & test_bit(IRQTF_FORCED_THREAD,
@@ -783,8 +794,12 @@ static int irq_thread(void *data)
 			desc->istate |= IRQS_PENDING;
 			raw_spin_unlock_irq(&desc->lock);
 		} else {
+			irqreturn_t action_ret;
+
 			raw_spin_unlock_irq(&desc->lock);
-			handler_fn(desc, action);
+			action_ret = handler_fn(desc, action);
+			if (!noirqdebug)
+				note_interrupt(action->irq, desc, action_ret);
 		}
 
 		wake = atomic_dec_and_test(&desc->threads_active);
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index dfbd550401b2..aa57d5da18c1 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -167,6 +167,13 @@ out:
 		  jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
 }
 
+static inline int bad_action_ret(irqreturn_t action_ret)
+{
+	if (likely(action_ret <= (IRQ_HANDLED | IRQ_WAKE_THREAD)))
+		return 0;
+	return 1;
+}
+
 /*
  * If 99,900 of the previous 100,000 interrupts have not been handled
  * then assume that the IRQ is stuck in some manner. Drop a diagnostic
@@ -182,7 +189,7 @@ __report_bad_irq(unsigned int irq, struct irq_desc *desc,
 	struct irqaction *action;
 	unsigned long flags;
 
-	if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) {
+	if (bad_action_ret(action_ret)) {
 		printk(KERN_ERR "irq event %d: bogus return value %x\n",
 				irq, action_ret);
 	} else {
@@ -201,10 +208,11 @@ __report_bad_irq(unsigned int irq, struct irq_desc *desc,
 	raw_spin_lock_irqsave(&desc->lock, flags);
 	action = desc->action;
 	while (action) {
-		printk(KERN_ERR "[<%p>]", action->handler);
-		print_symbol(" (%s)",
-			(unsigned long)action->handler);
-		printk("\n");
+		printk(KERN_ERR "[<%p>] %pf", action->handler, action->handler);
+		if (action->thread_fn)
+			printk(KERN_CONT " threaded [<%p>] %pf",
+					action->thread_fn, action->thread_fn);
+		printk(KERN_CONT "\n");
 		action = action->next;
 	}
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
@@ -262,7 +270,16 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
 	if (desc->istate & IRQS_POLL_INPROGRESS)
 		return;
 
-	if (unlikely(action_ret != IRQ_HANDLED)) {
+	/* we get here again via the threaded handler */
+	if (action_ret == IRQ_WAKE_THREAD)
+		return;
+
+	if (bad_action_ret(action_ret)) {
+		report_bad_irq(irq, desc, action_ret);
+		return;
+	}
+
+	if (unlikely(action_ret == IRQ_NONE)) {
 		/*
 		 * If we are seeing only the odd spurious IRQ caused by
 		 * bus asynchronicity then don't eventually trigger an error,
@@ -274,8 +291,6 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
 		else
 			desc->irqs_unhandled++;
 		desc->last_unhandled = jiffies;
-		if (unlikely(action_ret != IRQ_NONE))
-			report_bad_irq(irq, desc, action_ret);
 	}
 
 	if (unlikely(try_misrouted_irq(irq, desc, action_ret))) {
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 63437d065ac8..298c9276dfdb 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -3426,7 +3426,7 @@ int lock_is_held(struct lockdep_map *lock)
 	int ret = 0;
 
 	if (unlikely(current->lockdep_recursion))
-		return ret;
+		return 1; /* avoid false negative lockdep_assert_held() */
 
 	raw_local_irq_save(flags);
 	check_flags(flags);
diff --git a/kernel/sched.c b/kernel/sched.c
index cbb3a0eee58e..3f2e502d609b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -605,10 +605,10 @@ static inline int cpu_of(struct rq *rq)
 /*
  * Return the group to which this tasks belongs.
  *
- * We use task_subsys_state_check() and extend the RCU verification
- * with lockdep_is_held(&p->pi_lock) because cpu_cgroup_attach()
- * holds that lock for each task it moves into the cgroup. Therefore
- * by holding that lock, we pin the task to the current cgroup.
+ * We use task_subsys_state_check() and extend the RCU verification with
+ * pi->lock and rq->lock because cpu_cgroup_attach() holds those locks for each
+ * task it moves into the cgroup. Therefore by holding either of those locks,
+ * we pin the task to the current cgroup.
  */
 static inline struct task_group *task_group(struct task_struct *p)
 {
@@ -616,7 +616,8 @@ static inline struct task_group *task_group(struct task_struct *p)
 	struct cgroup_subsys_state *css;
 
 	css = task_subsys_state_check(p, cpu_cgroup_subsys_id,
-			lockdep_is_held(&p->pi_lock));
+			lockdep_is_held(&p->pi_lock) ||
+			lockdep_is_held(&task_rq(p)->lock));
 	tg = container_of(css, struct task_group, css);
 
 	return autogroup_task_group(p, tg);
@@ -2200,6 +2201,16 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
 			!(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE));
 
 #ifdef CONFIG_LOCKDEP
+	/*
+	 * The caller should hold either p->pi_lock or rq->lock, when changing
+	 * a task's CPU. ->pi_lock for waking tasks, rq->lock for runnable tasks.
+	 *
+	 * sched_move_task() holds both and thus holding either pins the cgroup,
+	 * see set_task_rq().
+	 *
+	 * Furthermore, all task_rq users should acquire both locks, see
+	 * task_rq_lock().
+	 */
 	WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) ||
 				      lockdep_is_held(&task_rq(p)->lock)));
 #endif
@@ -2447,6 +2458,10 @@ ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
 		}
 		rcu_read_unlock();
 	}
+
+	if (wake_flags & WF_MIGRATED)
+		schedstat_inc(p, se.statistics.nr_wakeups_migrate);
+
 #endif /* CONFIG_SMP */
 
 	schedstat_inc(rq, ttwu_count);
@@ -2455,9 +2470,6 @@ ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
 	if (wake_flags & WF_SYNC)
 		schedstat_inc(p, se.statistics.nr_wakeups_sync);
 
-	if (cpu != task_cpu(p))
-		schedstat_inc(p, se.statistics.nr_wakeups_migrate);
-
 #endif /* CONFIG_SCHEDSTATS */
 }
 
@@ -2600,6 +2612,7 @@ static void ttwu_queue(struct task_struct *p, int cpu)
 
 #if defined(CONFIG_SMP)
 	if (sched_feat(TTWU_QUEUE) && cpu != smp_processor_id()) {
+		sched_clock_cpu(cpu); /* sync clocks x-cpu */
 		ttwu_queue_remote(p, cpu);
 		return;
 	}
@@ -2674,8 +2687,10 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
 		p->sched_class->task_waking(p);
 
 	cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
-	if (task_cpu(p) != cpu)
+	if (task_cpu(p) != cpu) {
+		wake_flags |= WF_MIGRATED;
 		set_task_cpu(p, cpu);
+	}
 #endif /* CONFIG_SMP */
 
 	ttwu_queue(p, cpu);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 4fc92445a29c..f175d98bd355 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -938,6 +938,12 @@ static struct ctl_table kern_table[] = {
 	},
 #endif
 #ifdef CONFIG_PERF_EVENTS
+	/*
+	 * User-space scripts rely on the existence of this file
+	 * as a feature check for perf_events being enabled.
+	 *
+	 * So it's an ABI, do not remove!
+	 */
 	{
 		.procname	= "perf_event_paranoid",
 		.data		= &sysctl_perf_event_paranoid,
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index c027d4f602f1..e4c699dfa4e8 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -182,7 +182,10 @@ void clockevents_register_device(struct clock_event_device *dev)
 	unsigned long flags;
 
 	BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED);
-	BUG_ON(!dev->cpumask);
+	if (!dev->cpumask) {
+		WARN_ON(num_possible_cpus() > 1);
+		dev->cpumask = cpumask_of(smp_processor_id());
+	}
 
 	raw_spin_lock_irqsave(&clockevents_lock, flags);
 
diff --git a/kernel/timer.c b/kernel/timer.c
index fd6198692b57..8cff36119e4d 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -749,16 +749,15 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
 	unsigned long expires_limit, mask;
 	int bit;
 
-	expires_limit = expires;
-
 	if (timer->slack >= 0) {
 		expires_limit = expires + timer->slack;
 	} else {
-		unsigned long now = jiffies;
+		long delta = expires - jiffies;
+
+		if (delta < 256)
+			return expires;
 
-		/* No slack, if already expired else auto slack 0.4% */
-		if (time_after(expires, now))
-			expires_limit = expires + (expires - now)/256;
+		expires_limit = expires + delta / 256;
 	}
 	mask = expires ^ expires_limit;
 	if (mask == 0)
@@ -795,6 +794,8 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
  */
 int mod_timer(struct timer_list *timer, unsigned long expires)
 {
+	expires = apply_slack(timer, expires);
+
 	/*
 	 * This is a common optimization triggered by the
 	 * networking code - if the timer is re-modified
@@ -803,8 +804,6 @@ int mod_timer(struct timer_list *timer, unsigned long expires)
 	if (timer_pending(timer) && timer->expires == expires)
 		return 1;
 
-	expires = apply_slack(timer, expires);
-
 	return __mod_timer(timer, expires, false, TIMER_NOT_PINNED);
 }
 EXPORT_SYMBOL(mod_timer);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 1ee417fcbfa5..908038f57440 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2740,7 +2740,7 @@ static int ftrace_process_regex(struct ftrace_hash *hash,
 {
 	char *func, *command, *next = buff;
 	struct ftrace_func_command *p;
-	int ret;
+	int ret = -EINVAL;
 
 	func = strsep(&next, ":");
 
@@ -3330,6 +3330,7 @@ static int ftrace_process_locs(struct module *mod,
 {
 	unsigned long *p;
 	unsigned long addr;
+	unsigned long flags;
 
 	mutex_lock(&ftrace_lock);
 	p = start;
@@ -3346,7 +3347,13 @@ static int ftrace_process_locs(struct module *mod,
 		ftrace_record_ip(addr);
 	}
 
+	/*
+	 * Disable interrupts to prevent interrupts from executing
+	 * code that is being modified.
+	 */
+	local_irq_save(flags);
 	ftrace_update_code(mod);
+	local_irq_restore(flags);
 	mutex_unlock(&ftrace_lock);
 
 	return 0;
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index f925c45f0afa..27d13b36b8be 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1870,8 +1870,12 @@ fs_initcall(init_kprobe_trace);
 
 #ifdef CONFIG_FTRACE_STARTUP_TEST
 
-static int kprobe_trace_selftest_target(int a1, int a2, int a3,
-					int a4, int a5, int a6)
+/*
+ * The "__used" keeps gcc from removing the function symbol
+ * from the kallsyms table.
+ */
+static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
+					       int a4, int a5, int a6)
 {
 	return a1 + a2 + a3 + a4 + a5 + a6;
 }