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

[Luis Henriques]

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-3.5.y-queue branch of the 3.5.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-3.5.y-queue

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

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From b4060b52e683444388898d68ef824e710561cb2d 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: Luis Henriques <luis.henriques 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 aa58c02..0d15abe 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1354,6 +1354,7 @@ 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 5ad042c..2070e9c 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1630,6 +1630,7 @@ 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++;
--
1.8.3.2