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Diffstat (limited to 'kernel')
-rw-r--r--kernel/irq/manage.c3
-rw-r--r--kernel/profile.c3
-rw-r--r--kernel/sys.c15
3 files changed, 16 insertions, 5 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index b385878c6e80..8b961adc3bd2 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -315,6 +315,9 @@ int setup_irq(unsigned int irq, struct irqaction *new)
/* Undo nested disables: */
desc->depth = 1;
}
+ /* Reset broken irq detection when installing new handler */
+ desc->irq_count = 0;
+ desc->irqs_unhandled = 0;
spin_unlock_irqrestore(&desc->lock, flags);
new->irq = irq;
diff --git a/kernel/profile.c b/kernel/profile.c
index a6574a18514e..d6579d511069 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -331,7 +331,6 @@ out:
local_irq_restore(flags);
put_cpu();
}
-EXPORT_SYMBOL_GPL(profile_hits);
static int __devinit profile_cpu_callback(struct notifier_block *info,
unsigned long action, void *__cpu)
@@ -401,6 +400,8 @@ void profile_hits(int type, void *__pc, unsigned int nr_hits)
}
#endif /* !CONFIG_SMP */
+EXPORT_SYMBOL_GPL(profile_hits);
+
void profile_tick(int type)
{
struct pt_regs *regs = get_irq_regs();
diff --git a/kernel/sys.c b/kernel/sys.c
index c7675c1bfdf2..6e2101dec0fc 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -323,11 +323,18 @@ EXPORT_SYMBOL_GPL(blocking_notifier_chain_unregister);
int blocking_notifier_call_chain(struct blocking_notifier_head *nh,
unsigned long val, void *v)
{
- int ret;
+ int ret = NOTIFY_DONE;
- down_read(&nh->rwsem);
- ret = notifier_call_chain(&nh->head, val, v);
- up_read(&nh->rwsem);
+ /*
+ * We check the head outside the lock, but if this access is
+ * racy then it does not matter what the result of the test
+ * is, we re-check the list after having taken the lock anyway:
+ */
+ if (rcu_dereference(nh->head)) {
+ down_read(&nh->rwsem);
+ ret = notifier_call_chain(&nh->head, val, v);
+ up_read(&nh->rwsem);
+ }
return ret;
}