Commit 288eceb0 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: cec-adap.c: don't use flush_scheduled_work() 



For some inexplicable reason I decided to call flush_scheduled_work()
instead of cancel_delayed_work_sync(). The problem with that is that
flush_scheduled_work() waits for *all* queued scheduled work to be
completed instead of just the work itself.

This can cause a deadlock if a CEC driver also schedules work that
takes the same lock. See the comments for flush_scheduled_work() in
linux/workqueue.h.

This is exactly what has been observed a few times.

This patch simply replaces flush_scheduled_work() by
cancel_delayed_work_sync().

Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: <stable@vger.kernel.org>      # for v5.8 and up
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent ddecfc76

drivers/media/cec/core/cec-adap.c

+1 −1
Original line number Diff line number Diff line
@@ -1199,7 +1199,7 @@ void cec_received_msg_ts(struct cec_adapter *adap, 
			/* Cancel the pending timeout work */

			if (!cancel_delayed_work(&data->work)) {

				mutex_unlock(&adap->lock);

				flush_scheduled_work();

				cancel_delayed_work_sync(&data->work);

				mutex_lock(&adap->lock);

			}

			/*