On 9/29/18 9:26 AM, Shaohua Li wrote:
On Tue, Sep 25, 2018 at 11:06:54AM +0800, Guoqing Jiang wrote:
If we change the number of array's device after device
is removed from array, then add the device back to array,
we can see that device is added as active role instead of
spare which we expected.
Please see the below link for details:
https://marc.info/?l=linux-raid&m=153736982015076&w=2
This is caused by that we prefer to use device's previous
role which is recorded by saved_raid_disk, but we should
respect the new number of conf->raid_disks since it could
be changed after device is removed.
Fixes: 70bcecdb1534 (md-cluster: Improve md_reload_sb to be less error prone")
Reported-by: Gioh Kim <gi-oh.kim@xxxxxxxxxxxxxxxx>
Tested-by: Gioh Kim <gi-oh.kim@xxxxxxxxxxxxxxxx>
Signed-off-by: Guoqing Jiang <gqjiang@xxxxxxxx>
raid10 has similar code, I think we should fix it in generic code. does below
code work for you?
Yes, it is a better way.
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 63ceabb4e020..a25ebf81b266 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1774,6 +1774,10 @@ static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
} else
set_bit(In_sync, &rdev->flags);
rdev->raid_disk = role;
+ if (role >= mddev->raid_disks) {
+ rdev->saved_raid_disk = -1;
+ rdev->raid_disk = -1;
+ }
break;
}
if (sb->devflags & WriteMostly1)
Acked-by: Guoqing Jiang <gqjiang@xxxxxxxx>
Thanks,
Guoqing
