tree f1d1043d7d02ad6bde3b158807b28bcfdafa21f6
parent ba02508248e90a9d696aebd18b48a3290235b53c
author Ingo Molnar <mingo@elte.hu> 1123275927 +0200
committer Linus Torvalds <torvalds@g5.osdl.org> 1123282601 -0700

[PATCH] Fix semundo lock leakage

semundo->lock can leak if semundo->refcount goes from 2 to 1 while
another thread has it locked.  This causes major problems for PREEMPT
kernels.

The simplest fix for now is to undo the single-thread optimization.

This bug was found via relentless testing by Dominik Karall.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>