6.8-stable review patch. If anyone has any objections, please let me know.
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From: Joel Colledge joel.colledge@linbit.com
[ Upstream commit d14646f23300a5fc85be867bafdc0702c2002789 ]
If the worker thread is not woken due to a bio, then it is not woken at all. This causes the hung task check to trigger. This occurs, for instance, when no bios are submitted. Also when a delay of 0 is configured, delay_bio() returns without waking the worker.
Prevent the hung task check from triggering by creating the thread with kthread_run() instead of using kthread_create() directly.
Fixes: 70bbeb29fab0 ("dm delay: for short delays, use kthread instead of timers and wq") Signed-off-by: Joel Colledge joel.colledge@linbit.com Reviewed-by: Benjamin Marzinski bmarzins@redhat.com Signed-off-by: Mike Snitzer snitzer@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/dm-delay.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/md/dm-delay.c b/drivers/md/dm-delay.c index eec0daa4b227a..4ba12d5369949 100644 --- a/drivers/md/dm-delay.c +++ b/drivers/md/dm-delay.c @@ -269,8 +269,7 @@ static int delay_ctr(struct dm_target *ti, unsigned int argc, char **argv) * In case of small requested delays, use kthread instead of * timers and workqueue to achieve better latency. */ - dc->worker = kthread_create(&flush_worker_fn, dc, - "dm-delay-flush-worker"); + dc->worker = kthread_run(&flush_worker_fn, dc, "dm-delay-flush-worker"); if (IS_ERR(dc->worker)) { ret = PTR_ERR(dc->worker); dc->worker = NULL;