Merge branch 'master'

7 files changed, 75 insertions, 61 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index d61ba88f34e5..e882c6babf41 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -16,47 +16,76 @@
 #include <asm/semaphore.h>
 
 /* This protects CPUs going up and down... */
-DECLARE_MUTEX(cpucontrol);
-EXPORT_SYMBOL_GPL(cpucontrol);
+static DECLARE_MUTEX(cpucontrol);
 
 static struct notifier_block *cpu_chain;
 
-/*
- * Used to check by callers if they need to acquire the cpucontrol
- * or not to protect a cpu from being removed. Its sometimes required to
- * call these functions both for normal operations, and in response to
- * a cpu being added/removed. If the context of the call is in the same
- * thread context as a CPU hotplug thread, we dont need to take the lock
- * since its already protected
- * check drivers/cpufreq/cpufreq.c for its usage - Ashok Raj
- */
+#ifdef CONFIG_HOTPLUG_CPU
+static struct task_struct *lock_cpu_hotplug_owner;
+static int lock_cpu_hotplug_depth;
 
-int current_in_cpu_hotplug(void)
+static int __lock_cpu_hotplug(int interruptible)
 {
-	return (current->flags & PF_HOTPLUG_CPU);
+	int ret = 0;
+
+	if (lock_cpu_hotplug_owner != current) {
+		if (interruptible)
+			ret = down_interruptible(&cpucontrol);
+		else
+			down(&cpucontrol);
+	}
+
+	/*
+	 * Set only if we succeed in locking
+	 */
+	if (!ret) {
+		lock_cpu_hotplug_depth++;
+		lock_cpu_hotplug_owner = current;
+	}
+
+	return ret;
 }
 
-EXPORT_SYMBOL_GPL(current_in_cpu_hotplug);
+void lock_cpu_hotplug(void)
+{
+	__lock_cpu_hotplug(0);
+}
+EXPORT_SYMBOL_GPL(lock_cpu_hotplug);
 
+void unlock_cpu_hotplug(void)
+{
+	if (--lock_cpu_hotplug_depth == 0) {
+		lock_cpu_hotplug_owner = NULL;
+		up(&cpucontrol);
+	}
+}
+EXPORT_SYMBOL_GPL(unlock_cpu_hotplug);
+
+int lock_cpu_hotplug_interruptible(void)
+{
+	return __lock_cpu_hotplug(1);
+}
+EXPORT_SYMBOL_GPL(lock_cpu_hotplug_interruptible);
+#endif	/* CONFIG_HOTPLUG_CPU */
 
 /* Need to know about CPUs going up/down? */
 int register_cpu_notifier(struct notifier_block *nb)
 {
 	int ret;
 
-	if ((ret = down_interruptible(&cpucontrol)) != 0)
+	if ((ret = lock_cpu_hotplug_interruptible()) != 0)
 		return ret;
 	ret = notifier_chain_register(&cpu_chain, nb);
-	up(&cpucontrol);
+	unlock_cpu_hotplug();
 	return ret;
 }
 EXPORT_SYMBOL(register_cpu_notifier);
 
 void unregister_cpu_notifier(struct notifier_block *nb)
 {
-	down(&cpucontrol);
+	lock_cpu_hotplug();
 	notifier_chain_unregister(&cpu_chain, nb);
-	up(&cpucontrol);
+	unlock_cpu_hotplug();
 }
 EXPORT_SYMBOL(unregister_cpu_notifier);
 
@@ -112,13 +141,6 @@ int cpu_down(unsigned int cpu)
 		goto out;
 	}
 
-	/*
-	 * Leave a trace in current->flags indicating we are already in
-	 * process of performing CPU hotplug. Callers can check if cpucontrol
-	 * is already acquired by current thread, and if so not cause
-	 * a dead lock by not acquiring the lock
-	 */
-	current->flags |= PF_HOTPLUG_CPU;
 	err = notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE,
 						(void *)(long)cpu);
 	if (err == NOTIFY_BAD) {
@@ -171,7 +193,6 @@ out_thread:
 out_allowed:
 	set_cpus_allowed(current, old_allowed);
 out:
-	current->flags &= ~PF_HOTPLUG_CPU;
 	unlock_cpu_hotplug();
 	return err;
 }
@@ -182,7 +203,7 @@ int __devinit cpu_up(unsigned int cpu)
 	int ret;
 	void *hcpu = (void *)(long)cpu;
 
-	if ((ret = down_interruptible(&cpucontrol)) != 0)
+	if ((ret = lock_cpu_hotplug_interruptible()) != 0)
 		return ret;
 
 	if (cpu_online(cpu) || !cpu_present(cpu)) {
@@ -190,11 +211,6 @@ int __devinit cpu_up(unsigned int cpu)
 		goto out;
 	}
 
-	/*
-	 * Leave a trace in current->flags indicating we are already in
-	 * process of performing CPU hotplug.
-	 */
-	current->flags |= PF_HOTPLUG_CPU;
 	ret = notifier_call_chain(&cpu_chain, CPU_UP_PREPARE, hcpu);
 	if (ret == NOTIFY_BAD) {
 		printk("%s: attempt to bring up CPU %u failed\n",
@@ -217,7 +233,6 @@ out_notify:
 	if (ret != 0)
 		notifier_call_chain(&cpu_chain, CPU_UP_CANCELED, hcpu);
 out:
-	current->flags &= ~PF_HOTPLUG_CPU;
-	up(&cpucontrol);
+	unlock_cpu_hotplug();
 	return ret;
 }
diff --git a/kernel/fork.c b/kernel/fork.c
index e0d0b77343f8..fb8572a42297 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -263,7 +263,7 @@ static inline int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 		rb_parent = &tmp->vm_rb;
 
 		mm->map_count++;
-		retval = copy_page_range(mm, oldmm, tmp);
+		retval = copy_page_range(mm, oldmm, mpnt);
 
 		if (tmp->vm_ops && tmp->vm_ops->open)
 			tmp->vm_ops->open(tmp);
@@ -1124,8 +1124,6 @@ static task_t *copy_process(unsigned long clone_flags,
 	if (unlikely(p->ptrace & PT_PTRACED))
 		__ptrace_link(p, current->parent);
 
-	cpuset_fork(p);
-
 	attach_pid(p, PIDTYPE_PID, p->pid);
 	attach_pid(p, PIDTYPE_TGID, p->tgid);
 	if (thread_group_leader(p)) {
@@ -1135,13 +1133,14 @@ static task_t *copy_process(unsigned long clone_flags,
 			__get_cpu_var(process_counts)++;
 	}
 
-	proc_fork_connector(p);
 	if (!current->signal->tty && p->signal->tty)
 		p->signal->tty = NULL;
 
 	nr_threads++;
 	total_forks++;
 	write_unlock_irq(&tasklist_lock);
+	proc_fork_connector(p);
+	cpuset_fork(p);
 	retval = 0;
 
 fork_out:
diff --git a/kernel/futex.c b/kernel/futex.c
index aca8d10704f6..5872e3507f35 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -201,21 +201,6 @@ static int get_futex_key(unsigned long uaddr, union futex_key *key)
 	 * from swap.  But that's a lot of code to duplicate here
 	 * for a rare case, so we simply fetch the page.
 	 */
-
-	/*
-	 * Do a quick atomic lookup first - this is the fastpath.
-	 */
-	page = follow_page(mm, uaddr, FOLL_TOUCH|FOLL_GET);
-	if (likely(page != NULL)) {
-		key->shared.pgoff =
-			page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
-		put_page(page);
-		return 0;
-	}
-
-	/*
-	 * Do it the general way.
-	 */
 	err = get_user_pages(current, mm, uaddr, 1, 0, 0, &page, NULL);
 	if (err >= 0) {
 		key->shared.pgoff =
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 3bd7226d15fa..81c49a4d679e 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -36,6 +36,9 @@ void synchronize_irq(unsigned int irq)
 {
 	struct irq_desc *desc = irq_desc + irq;
 
+	if (irq >= NR_IRQS)
+		return;
+
 	while (desc->status & IRQ_INPROGRESS)
 		cpu_relax();
 }
@@ -60,6 +63,9 @@ void disable_irq_nosync(unsigned int irq)
 	irq_desc_t *desc = irq_desc + irq;
 	unsigned long flags;
 
+	if (irq >= NR_IRQS)
+		return;
+
 	spin_lock_irqsave(&desc->lock, flags);
 	if (!desc->depth++) {
 		desc->status |= IRQ_DISABLED;
@@ -86,6 +92,9 @@ void disable_irq(unsigned int irq)
 {
 	irq_desc_t *desc = irq_desc + irq;
 
+	if (irq >= NR_IRQS)
+		return;
+
 	disable_irq_nosync(irq);
 	if (desc->action)
 		synchronize_irq(irq);
@@ -108,6 +117,9 @@ void enable_irq(unsigned int irq)
 	irq_desc_t *desc = irq_desc + irq;
 	unsigned long flags;
 
+	if (irq >= NR_IRQS)
+		return;
+
 	spin_lock_irqsave(&desc->lock, flags);
 	switch (desc->depth) {
 	case 0:
@@ -163,6 +175,9 @@ int setup_irq(unsigned int irq, struct irqaction * new)
 	unsigned long flags;
 	int shared = 0;
 
+	if (irq >= NR_IRQS)
+		return -EINVAL;
+
 	if (desc->handler == &no_irq_type)
 		return -ENOSYS;
 	/*
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 84af54c39e1b..cae4f5728997 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -36,7 +36,7 @@ timespec_to_sample(clockid_t which_clock, const struct timespec *tp)
 	union cpu_time_count ret;
 	ret.sched = 0;		/* high half always zero when .cpu used */
 	if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) {
-		ret.sched = tp->tv_sec * NSEC_PER_SEC + tp->tv_nsec;
+		ret.sched = (unsigned long long)tp->tv_sec * NSEC_PER_SEC + tp->tv_nsec;
 	} else {
 		ret.cpu = timespec_to_cputime(tp);
 	}
diff --git a/kernel/printk.c b/kernel/printk.c
index ac8a08f36207..5287be83e3e7 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -956,7 +956,7 @@ int unregister_console(struct console *console)
 	if (console_drivers == console) {
 		console_drivers=console->next;
 		res = 0;
-	} else {
+	} else if (console_drivers) {
 		for (a=console_drivers->next, b=console_drivers ;
 		     a; b=a, a=b->next) {
 			if (a == console) {
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 42df83d7fad2..2bd5aee1c736 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -102,7 +102,7 @@ int fastcall queue_work(struct workqueue_struct *wq, struct work_struct *work)
 
 	if (!test_and_set_bit(0, &work->pending)) {
 		if (unlikely(is_single_threaded(wq)))
-			cpu = 0;
+			cpu = any_online_cpu(cpu_online_map);
 		BUG_ON(!list_empty(&work->entry));
 		__queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work);
 		ret = 1;
@@ -118,7 +118,7 @@ static void delayed_work_timer_fn(unsigned long __data)
 	int cpu = smp_processor_id();
 
 	if (unlikely(is_single_threaded(wq)))
-		cpu = 0;
+		cpu = any_online_cpu(cpu_online_map);
 
 	__queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work);
 }
@@ -266,8 +266,8 @@ void fastcall flush_workqueue(struct workqueue_struct *wq)
 	might_sleep();
 
 	if (is_single_threaded(wq)) {
-		/* Always use cpu 0's area. */
-		flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, 0));
+		/* Always use first cpu's area. */
+		flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, any_online_cpu(cpu_online_map)));
 	} else {
 		int cpu;
 
@@ -320,7 +320,7 @@ struct workqueue_struct *__create_workqueue(const char *name,
 	lock_cpu_hotplug();
 	if (singlethread) {
 		INIT_LIST_HEAD(&wq->list);
-		p = create_workqueue_thread(wq, 0);
+		p = create_workqueue_thread(wq, any_online_cpu(cpu_online_map));
 		if (!p)
 			destroy = 1;
 		else
@@ -374,7 +374,7 @@ void destroy_workqueue(struct workqueue_struct *wq)
 	/* We don't need the distraction of CPUs appearing and vanishing. */
 	lock_cpu_hotplug();
 	if (is_single_threaded(wq))
-		cleanup_workqueue_thread(wq, 0);
+		cleanup_workqueue_thread(wq, any_online_cpu(cpu_online_map));
 	else {
 		for_each_online_cpu(cpu)
 			cleanup_workqueue_thread(wq, cpu);