lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[PATCH] lockdep: avoid lockdep warning in md

Browse Source 
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 <mingo@elte.hu>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
NeilBrown
2006-12-08 02:36:17 -08:00
committed by Linus Torvalds
parent 6796bf54a6
commit d63a5a74de
3 changed files with 12 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
kernel/mutex.c
View File

@@ -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
/*