[PATCH 6.18 052/122] bcache: fix I/O accounting leak in detached_dev_do_request

Greg Kroah-Hartman
2026-02-04T15:30:54Z

From: Shida Zhang <zhangshida@kylinos.cn>

[ Upstream commit 4da7c5c3ec34d839bba6e035c3d05c447a2f9d4f ]

When a bcache device is detached, discard requests are completed
immediately. However, the I/O accounting started in
cached_dev_make_request() is not ended, leading to 100% disk
utilization reports in iostat. Add the missing bio_end_io_acct() call.

Fixes: cafe56359144 ("bcache: A block layer cache")
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Acked-by: Coly Li <colyli@fnnas.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/md/bcache/request.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index a02aecac05cdf..6cba1180be8aa 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1107,6 +1107,7 @@ static void detached_dev_do_request(struct bcache_device *d,

if (bio_op(orig_bio) == REQ_OP_DISCARD &&
!bdev_max_discard_sectors(dc->bdev)) {
+ bio_end_io_acct(orig_bio, start_time);
bio_endio(orig_bio);
return;
}
--
2.51.0