Re: [PATCH] md: fix bi_status reporting in md_end_clone_io
From: Yu Kuai <hidden>
Date: 2023-11-20 01:05:18
在 2023/11/18 8:39, Song Liu 写道:
md_end_clone_io() may overwrite error status in orig_bio->bi_status with BLK_STS_OK. This could happen when orig_bio has BIO_CHAIN (split by md_submit_bio => bio_split_to_limits, for example). As a result, upper layer may miss error reported from md (or the device) and consider the failed IO was successful. Fix this by only update orig_bio->bi_status when current bio reports error and orig_bio is BLK_STS_OK. This is the same behavior as __bio_chain_endio().
LGTM Reviewed-by: Yu Kuai <redacted>
quoted hunk ↗ jump to hunk
Fixes: 10764815ff47 ("md: add io accounting for raid0 and raid5") Reported-by: Bhanu Victor DiCara <redacted> Closes: https://lore.kernel.org/regressions/5727380.DvuYhMxLoT@bvd0/ (local) Signed-off-by: Song Liu <song@kernel.org> Tested-by: Xiao Ni <redacted> Cc: Guoqing Jiang <redacted> --- drivers/md/md.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)diff --git a/drivers/md/md.c b/drivers/md/md.c index 4ee4593c874a..c94373d64f2c 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c@@ -8666,7 +8666,8 @@ static void md_end_clone_io(struct bio *bio) struct bio *orig_bio = md_io_clone->orig_bio; struct mddev *mddev = md_io_clone->mddev; - orig_bio->bi_status = bio->bi_status; + if (bio->bi_status && !orig_bio->bi_status) + orig_bio->bi_status = bio->bi_status; if (md_io_clone->start_time) bio_end_io_acct(orig_bio, md_io_clone->start_time);