diff mbox series

[1/9] bfq: Avoid false marking of bic as stably merged

Message ID 20220401102752.8599-1-jack@suse.cz (mailing list archive)
State New, archived
Headers show
Series bfq: Avoid use-after-free when moving processes between cgroups | expand

Commit Message

Jan Kara April 1, 2022, 10:27 a.m. UTC 
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)" <yukuai3@huawei.com>
Fixes: 430a67f9d616 ("block, bfq: merge bursts of newly-created queues")
Signed-off-by: Jan Kara <jack@suse.cz>
---
 block/bfq-iosched.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Jens Axboe April 18, 2022, 1:34 a.m. UTC | #1 
On Fri, 1 Apr 2022 12:27:42 +0200, Jan Kara wrote:
> 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.
> 
> 

Applied, thanks!

[1/9] bfq: Avoid false marking of bic as stably merged
      commit: 70456e5210f40ffdb8f6d905acfdcec5bd5fad9e
[2/9] bfq: Avoid merging queues with different parents
      commit: c1cee4ab36acef271be9101590756ed0c0c374d9
[3/9] bfq: Split shared queues on move between cgroups
      commit: 3bc5e683c67d94bd839a1da2e796c15847b51b69
[4/9] bfq: Update cgroup information before merging bio
      commit: ea591cd4eb270393810e7be01feb8fde6a34fbbe
[5/9] bfq: Drop pointless unlock-lock pair
      commit: fc84e1f941b91221092da5b3102ec82da24c5673
[6/9] bfq: Remove pointless bfq_init_rq() calls
      commit: 5f550ede5edf846ecc0067be1ba80514e6fe7f8e
[7/9] bfq: Track whether bfq_group is still online
      commit: 09f871868080c33992cd6a9b72a5ca49582578fa
[8/9] bfq: Get rid of __bio_blkcg() usage
      commit: 4e54a2493e582361adc3bfbf06c7d50d19d18837
[9/9] bfq: Make sure bfqg for which we are queueing requests is online
      commit: 075a53b78b815301f8d3dd1ee2cd99554e34f0dd

Best regards,
diff mbox series

Patch

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;