bfq_setup_cooperator() can mark bic as stably merged even though it decides to not merge its bfqqs (when bfq_setup_merge() returns NULL). Make sure to mark bic as stably merged only if we are really going to merge bfqqs. CC: stable@xxxxxxxxxxxxxxx Tested-by: "yukuai (C)" <yukuai3@xxxxxxxxxx> Fixes: 430a67f9d616 ("block, bfq: merge bursts of newly-created queues") Signed-off-by: Jan Kara <jack@xxxxxxx> --- block/bfq-iosched.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 2e0dd68a3cbe..6d122c28086e 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -2895,9 +2895,12 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq, struct bfq_queue *new_bfqq = bfq_setup_merge(bfqq, stable_merge_bfqq); - bic->stably_merged = true; - if (new_bfqq && new_bfqq->bic) - new_bfqq->bic->stably_merged = true; + if (new_bfqq) { + bic->stably_merged = true; + if (new_bfqq->bic) + new_bfqq->bic->stably_merged = + true; + } return new_bfqq; } else return NULL; -- 2.34.1