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: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # for v5.8 and up
Fixes: 9881fe0ca187 ("[media] cec: add HDMI CEC framework (adapter)")
---
drivers/media/cec/core/cec-adap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/cec/core/cec-adap.c b/drivers/media/cec/core/cec-adap.c
index 80fd5165f658..3153c401cb65 100644
--- a/drivers/media/cec/core/cec-adap.c
+++ b/drivers/media/cec/core/cec-adap.c
@@ -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);
}
/*
--
2.27.0
