| From fc4b514f2727f74a4587c31db87e0e93465518c3 Mon Sep 17 00:00:00 2001 |
| From: Tejun Heo <tj@kernel.org> |
| Date: Tue, 4 Dec 2012 07:40:39 -0800 |
| Subject: workqueue: convert BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s |
| |
| From: Tejun Heo <tj@kernel.org> |
| |
| commit fc4b514f2727f74a4587c31db87e0e93465518c3 upstream. |
| |
| 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 <tj@kernel.org> |
| Cc: Xiaotian Feng <xtfeng@gmail.com> |
| Signed-off-by: Shuah Khan <shuah.khan@hp.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| kernel/workqueue.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/kernel/workqueue.c |
| +++ b/kernel/workqueue.c |
| @@ -1141,8 +1141,8 @@ int queue_delayed_work_on(int cpu, struc |
| if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) { |
| unsigned int lcpu; |
| |
| - BUG_ON(timer_pending(timer)); |
| - BUG_ON(!list_empty(&work->entry)); |
| + WARN_ON_ONCE(timer_pending(timer)); |
| + WARN_ON_ONCE(!list_empty(&work->entry)); |
| |
| timer_stats_timer_set_start_info(&dwork->timer); |
| |