Atomic underflow debugging in this kernel exposed a bug in the AVC RCU
code, fix below.  The effect of this bug would be delayed node reclamation.
Signed-off-by: James Morris <jmorris@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>