tree 8b12bc626b8f1507b7b550865c5f8282bcac6c27
parent 6796bf54a64df36f96a42ae222423fffe36c58a5
author NeilBrown <neilb@suse.de> 1165574177 -0800
committer Linus Torvalds <torvalds@woody.osdl.org> 1165595319 -0800

[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 <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>