On Tue, Mar 08, 2022 at 05:09:15PM +0900, Shin'ichiro Kawasaki wrote:
> Commit 9d497e2941c3 ("block: don't protect submit_bio_checks by
> q_usage_counter") moved blk_mq_attempt_bio_merge and rq_qos_throttle
> calls out of q_usage_counter protection. However, these functions require
> q_usage_counter protection. The blk_mq_attempt_bio_merge call without
> the protection resulted in blktests block/005 failure with KASAN null-
> ptr-deref or use-after-free at bio merge. The rq_qos_throttle call
> without the protection caused kernel hang at qos throttle.
>
> To fix the failures, move the blk_mq_attempt_bio_merge and
> rq_qos_throttle calls back to q_usage_counter protection.
>
> Fixes: 9d497e2941c3 ("block: don't protect submit_bio_checks by q_usage_counter")
> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
Looks fine,
Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
Thanks,
Ming
