From d639a4c0df2b1efc9db84d88c9803d8478427752 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Fri, 1 Apr 2022 12:27:42 +0200 Subject: [PATCH] bfq: Avoid false marking of bic as stably merged commit 70456e5210f40ffdb8f6d905acfdcec5bd5fad9e upstream. 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@vger.kernel.org Tested-by: "yukuai (C)" Fixes: 430a67f9d616 ("block, bfq: merge bursts of newly-created queues") Signed-off-by: Jan Kara Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20220401102752.8599-1-jack@suse.cz Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- 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 343ca55..95420e1 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -2773,9 +2773,12 @@ 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; -- 2.7.4