From: Tejun Heo Date: Tue, 4 Dec 2012 15:40:39 +0000 (-0800) Subject: workqueue: convert BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s X-Git-Tag: upstream/snapshot3+hdmi~6167^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fc4b514f2727f74a4587c31db87e0e93465518c3;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git workqueue: convert BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s 8852aac25e ("workqueue: mod_delayed_work_on() shouldn't queue timer on 0 delay") unexpectedly uncovered a very nasty abuse of delayed_work in megaraid - it allocated work_struct, casted it to delayed_work and then pass that into queue_delayed_work(). Previously, this was okay because 0 @delay short-circuited to queue_work() before doing anything with delayed_work. 8852aac25e moved 0 @delay test into __queue_delayed_work() after sanity check on delayed_work making megaraid trigger BUG_ON(). Although megaraid is already fixed by c1d390d8e6 ("megaraid: fix BUG_ON() from incorrect use of delayed work"), this patch converts BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s so that such abusers, if there are more, trigger warning but don't crash the machine. Signed-off-by: Tejun Heo Cc: Xiaotian Feng --- diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 084aa47..1dae900 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1361,8 +1361,8 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq, WARN_ON_ONCE(timer->function != delayed_work_timer_fn || timer->data != (unsigned long)dwork); - BUG_ON(timer_pending(timer)); - BUG_ON(!list_empty(&work->entry)); + WARN_ON_ONCE(timer_pending(timer)); + WARN_ON_ONCE(!list_empty(&work->entry)); /* * If @delay is 0, queue @dwork->work immediately. This is for