md: prevent incorrect update of resync/recovery offset

[ Upstream commit 7202082b7b7a256d04ec96131c7f859df0a79f64 ]

In md_do_sync(), when md_sync_action returns ACTION_FROZEN, subsequent
call to md_sync_position() will return MaxSector. This causes
'curr_resync' (and later 'recovery_offset') to be set to MaxSector too,
which incorrectly signals that recovery/resync has completed, even though
disk data has not actually been updated.

To fix this issue, skip updating any offset values when the sync action
is FROZEN. The same holds true for IDLE.

Fixes: 7d9f107a4e94 ("md: use new helpers in md_do_sync()")
Signed-off-by: Li Nan <linan122@huawei.com>
Link: https://lore.kernel.org/linux-raid/20250904073452.3408516-1-linan666@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 4b32917236703ef3ac08c236f34a838182c74f98..d2630764429247b78d69cd86b73244b87a195f56 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8996,6 +8996,11 @@ void md_do_sync(struct md_thread *thread)
        }
 
        action = md_sync_action(mddev);
+       if (action == ACTION_FROZEN || action == ACTION_IDLE) {
+               set_bit(MD_RECOVERY_INTR, &mddev->recovery);
+               goto skip;
+       }
+
        desc = md_sync_action_name(action);
        mddev->last_sync_action = action;