From: NeilBrown Date: Sat, 31 Oct 2015 00:00:56 +0000 (+1100) Subject: Revert "md: allow a partially recovered device to be hot-added to an array." X-Git-Tag: v4.3~7^2 X-Git-Url: https://git.kernelconcepts.de/?p=karo-tx-linux.git;a=commitdiff_plain;h=d01552a76d71f9879af448e9142389ee9be6e95b Revert "md: allow a partially recovered device to be hot-added to an array." This reverts commit 7eb418851f3278de67126ea0c427641ab4792c57. This commit is poorly justified, I can find not discusison in email, and it clearly causes a problem. If a device which is being recovered fails and is subsequently re-added to an array, there could easily have been changes to the array *before* the point where the recovery was up to. So the recovery must start again from the beginning. If a spare is being recovered and fails, then when it is re-added we really should do a bitmap-based recovery up to the recovery-offset, and then a full recovery from there. Before this reversion, we only did the "full recovery from there" which is not corect. After this reversion with will do a full recovery from the start, which is safer but not ideal. It will be left to a future patch to arrange the two different styles of recovery. Reported-and-tested-by: Nate Dailey Signed-off-by: NeilBrown Cc: stable@vger.kernel.org (3.14+) Fixes: 7eb418851f32 ("md: allow a partially recovered device to be hot-added to an array.") --- diff --git a/drivers/md/md.c b/drivers/md/md.c index c702de18207a..3fe3d04a968a 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -8040,8 +8040,7 @@ static int remove_and_add_spares(struct mddev *mddev, !test_bit(Bitmap_sync, &rdev->flags))) continue; - if (rdev->saved_raid_disk < 0) - rdev->recovery_offset = 0; + rdev->recovery_offset = 0; if (mddev->pers-> hot_add_disk(mddev, rdev) == 0) { if (sysfs_link_rdev(mddev, rdev))