[3.8.y.z extended stable] Patch "md: Fix skipping recovery for read-only arrays." has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    md: Fix skipping recovery for read-only arrays.

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.13.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 854eded51db42a759868c732449a5b55bb12b0ac Mon Sep 17 00:00:00 2001
From: Lukasz Dorau <lukasz.dorau at intel.com>
Date: Thu, 24 Oct 2013 12:55:17 +1100
Subject: md: Fix skipping recovery for read-only arrays.

commit 61e4947c99c4494336254ec540c50186d186150b upstream.

Since:
        commit 7ceb17e87bde79d285a8b988cfed9eaeebe60b86
        md: Allow devices to be re-added to a read-only array.

spares are activated on a read-only array. In case of raid1 and raid10
personalities it causes that not-in-sync devices are marked in-sync
without checking if recovery has been finished.

If a read-only array is degraded and one of its devices is not in-sync
(because the array has been only partially recovered) recovery will be skipped.

This patch adds checking if recovery has been finished before marking a device
in-sync for raid1 and raid10 personalities. In case of raid5 personality
such condition is already present (at raid5.c:6029).

Bug was introduced in 3.10 and causes data corruption.

Signed-off-by: Pawel Baldysiak <pawel.baldysiak at intel.com>
Signed-off-by: Lukasz Dorau <lukasz.dorau at intel.com>
Signed-off-by: NeilBrown <neilb at suse.de>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/md/raid1.c  | 1 +
 drivers/md/raid10.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index a382d84..21f0c3f 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1493,6 +1493,7 @@ static int raid1_spare_active(struct mddev *mddev)
 			}
 		}
 		if (rdev
+		    && rdev->recovery_offset == MaxSector
 		    && !test_bit(Faulty, &rdev->flags)
 		    && !test_and_set_bit(In_sync, &rdev->flags)) {
 			count++;
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 92858ab..b8f5688 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1718,6 +1718,7 @@ static int raid10_spare_active(struct mddev *mddev)
 			}
 			sysfs_notify_dirent_safe(tmp->replacement->sysfs_state);
 		} else if (tmp->rdev
+			   && tmp->rdev->recovery_offset == MaxSector
 			   && !test_bit(Faulty, &tmp->rdev->flags)
 			   && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
 			count++;
--
1.8.1.2