md: prevent incorrect update of resync/recovery offset

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>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 1baaf52c603c1c229331771749a69bec6101e5ef..4e033c26fdd461c9aea2a2eb460f699e6839d984 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -9125,6 +9125,11 @@ 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;