From d63a5a74dee87883fda6b7d170244acaac5b05e8 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Fri, 8 Dec 2006 02:36:17 -0800 Subject: [PATCH] lockdep: avoid lockdep warning in md md_open takes ->reconfig_mutex which causes lockdep to complain. This (normally) doesn't have deadlock potential as the possible conflict is with a reconfig_mutex in a different device. I say "normally" because if a loop were created in the array->member hierarchy a deadlock could happen. However that causes bigger problems than a deadlock and should be fixed independently. So we flag the lock in md_open as a nested lock. This requires defining mutex_lock_interruptible_nested. Cc: Ingo Molnar Acked-by: Peter Zijlstra Acked-by: Ingo Molnar Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/mutex.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'kernel') diff --git a/kernel/mutex.c b/kernel/mutex.c index 8c71cf72a49..e7cbbb82765 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -206,6 +206,15 @@ mutex_lock_nested(struct mutex *lock, unsigned int subclass) } EXPORT_SYMBOL_GPL(mutex_lock_nested); + +int __sched +mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass) +{ + might_sleep(); + return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, subclass); +} + +EXPORT_SYMBOL_GPL(mutex_lock_interruptible_nested); #endif /* -- cgit v1.2.3