From: NeilBrown Date: Mon, 31 Oct 2011 01:59:44 +0000 (+1100) Subject: md/raid10: Fix bug when activating a hot-spare. X-Git-Tag: v3.2-rc1~115^2 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=7fcc7c8acf0fba44d19a713207af7e58267c1179;p=linux.git md/raid10: Fix bug when activating a hot-spare. This is a fairly serious bug in RAID10. When a RAID10 array is degraded and a hot-spare is activated, the spare does not take up the empty slot, but rather replaces the first working device. This is likely to make the array non-functional. It would normally be possible to recover the data, but that would need care and is not guaranteed. This bug was introduced in commit 2bb77736ae5dca0a189829fbb7379d43364a9dac which first appeared in 3.1. Cc: stable@kernel.org Signed-off-by: NeilBrown --- diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 132c18ef8665..c025a8276dc1 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1355,7 +1355,7 @@ static int raid10_add_disk(struct mddev *mddev, struct md_rdev *rdev) struct mirror_info *p = &conf->mirrors[mirror]; if (p->recovery_disabled == mddev->recovery_disabled) continue; - if (!p->rdev) + if (p->rdev) continue; disk_stack_limits(mddev->gendisk, rdev->bdev,