dm raid: fix false positive for requeue needed during reshape

[ Upstream commit b25b8f4b8ecef0f48c05f0c3572daeabefe16526 ]

An empty flush doesn't have a payload, so it should never be looked at
when considering to possibly requeue a bio for the case when a reshape
is in progress.

Fixes: 9dbd1aa3a81c ("dm raid: add reshaping support to the target")
Reported-by: Patrick Plenefisch <simonpatp@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 140bdf2a6ee118309db1245ff70f31e28f79da13..e523ecdf947f4ef2a2037283f08998d866542453 100644 (file)
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3329,14 +3329,14 @@ static int raid_map(struct dm_target *ti, struct bio *bio)
        struct mddev *mddev = &rs->md;
 
        /*
-        * If we're reshaping to add disk(s)), ti->len and
+        * If we're reshaping to add disk(s), ti->len and
         * mddev->array_sectors will differ during the process
         * (ti->len > mddev->array_sectors), so we have to requeue
         * bios with addresses > mddev->array_sectors here or
         * there will occur accesses past EOD of the component
         * data images thus erroring the raid set.
         */
-       if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
+       if (unlikely(bio_has_data(bio) && bio_end_sector(bio) > mddev->array_sectors))
                return DM_MAPIO_REQUEUE;
 
        md_handle_request(mddev, bio);