From: Guoqing Jiang <jgq516@xxxxxxxxx> [ Upstream commit 062f5b2ae12a153644c765e7ba3b0f825427be1d ] When a disk is added to array, the following path is called in mdadm. Manage_subdevs -> sysfs_freeze_array -> Manage_add -> sysfs_set_str(&info, NULL, "sync_action","idle") Then from kernel side, Manage_add invokes the path (add_new_disk -> validate_super = super_1_validate) to set In_sync flag. Since In_sync means "device is in_sync with rest of array", and the new added disk need to resync thread to help the synchronization of data. And md_reap_sync_thread would call spare_active to set In_sync for the new added disk finally. So don't set In_sync if array is in frozen. Signed-off-by: Guoqing Jiang <guoqing.jiang@xxxxxxxxxxxxxxx> Signed-off-by: Song Liu <songliubraving@xxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/md/md.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index c1c514792457a..da8708b65356e 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1662,8 +1662,15 @@ static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev) if (!(le32_to_cpu(sb->feature_map) & MD_FEATURE_RECOVERY_BITMAP)) rdev->saved_raid_disk = -1; - } else - set_bit(In_sync, &rdev->flags); + } else { + /* + * If the array is FROZEN, then the device can't + * be in_sync with rest of array. + */ + if (!test_bit(MD_RECOVERY_FROZEN, + &mddev->recovery)) + set_bit(In_sync, &rdev->flags); + } rdev->raid_disk = role; break; } -- 2.20.1