workqueue: trigger WARN if queue_delayed_work() is called with NULL @wq
authorTejun Heo <tj@kernel.org>
Mon, 6 Mar 2017 20:33:42 +0000 (15:33 -0500)
committerTejun Heo <tj@kernel.org>
Mon, 6 Mar 2017 20:33:42 +0000 (15:33 -0500)
commit637fdbae60d6cb9f6e963c1079d7e0445c86ff7d
tree3b785d958b7c02d45d3ce9e4076af530d0a34885
parentc1ae3cfa0e89fa1a7ecc4c99031f5e9ae99d9201
workqueue: trigger WARN if queue_delayed_work() is called with NULL @wq

If queue_delayed_work() gets called with NULL @wq, the kernel will
oops asynchronuosly on timer expiration which isn't too helpful in
tracking down the offender.  This actually happened with smc.

__queue_delayed_work() already does several input sanity checks
synchronously.  Add NULL @wq check.

Reported-by: Dave Jones <davej@codemonkey.org.uk>
Link: http://lkml.kernel.org/r/20170227171439.jshx3qplflyrgcv7@codemonkey.org.uk
Signed-off-by: Tejun Heo <tj@kernel.org>
kernel/workqueue.c