FAILED: patch "[PATCH] blk-mq: end the request if getting a keyslot fails" failed to apply to 6.6-stable tree

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x e67cb6ed40e7f45912b63d7d575f18dfd2ebc98a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '[email protected]' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From e67cb6ed40e7f45912b63d7d575f18dfd2ebc98a Mon Sep 17 00:00:00 2001
From: Josef Bacik <[email protected]>
Date: Thu, 29 Oct 2026 20:01:10 +0000
Subject: [PATCH] blk-mq: end the request if getting a keyslot fails

When blk_crypto_rq_get_keyslot() fails, blk_mq_submit_bio() ends the bio by hand and frees the request. By then blk_mq_bio_to_request() has done the IO accounting, which blk_mq_free_request() doesn't undo, so the in_flight counter never drops and iostat shows a device that is 100% busy. If the bio went through zone write plugging the zone stays plugged as well, and every later write to it waits forever.

Use blk_mq_end_request() like the dispatch path does for a request the driver rejected, after marking it for zone write plugging.

Move the call to blk_zone_write_plug_init_request() before blk_crypto_rq_get_keyslot() so that it doesn't need to be duplicated. It doesn't depend on the keyslot.

---
 block/blk-mq.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

index d9ab295be4d92..e5b9898cede98 100644
@@ -3209,16 +3209,15 @@ void blk_mq_submit_bio(struct bio *bio)
 
 	blk_mq_bio_to_request(rq, bio, nr_segs);
 
+	if (bio_zone_write_plugging(bio))
+		blk_zone_write_plug_init_request(rq);
+
 	ret = blk_crypto_rq_get_keyslot(rq);
 	if (ret != BLK_STS_OK) {
-		bio_endio_status(bio, ret);
-		blk_mq_free_request(rq);
+		blk_mq_end_request(rq, ret);
 		return;
 	}
 
-	if (bio_zone_write_plugging(bio))
-		blk_zone_write_plug_init_request(rq);
-
 	if (op_is_flush(bio->bi_opf) && blk_insert_flush(rq))
 		return;
 

2.53.0