md/raid1,raid10: always abort recover on write error.

commit 2446dba03f9dabe0b477a126cbeb377854785b47 upstream.

Currently we don't abort recovery on a write error if the write error
to the recovering device was triggerd by normal IO (as opposed to
recovery IO).

This means that for one bitmap region, the recovery might write to the
recovering device for a few sectors, then not bother for subsequent
sectors (as it never writes to failed devices).  In this case
the bitmap bit will be cleared, but it really shouldn't.

The result is that if the recovering device fails and is then re-added
(after fixing whatever hardware problem triggerred the failure),
the second recovery won't redo the region it was in the middle of,
so some of the device will not be recovered properly.

If we abort the recovery, the region being processes will be cancelled
(bit not cleared) and the whole region will be retried.

As the bug can result in data corruption the patch is suitable for
-stable.  For kernels prior to 3.11 there is a conflict in raid10.c
which will require care.

Original-from: jiao hui <jiaohui@bwstor.com.cn>
Reported-and-tested-by: jiao hui <jiaohui@bwstor.com.cn>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 75771b2077c00f28950169956f9ac4baf21cbe4d..a176791509f62bc842cf855f75a787f83fb280de 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1406,12 +1406,12 @@ static void error(struct mddev *mddev, struct md_rdev *rdev)
                mddev->degraded++;
                set_bit(Faulty, &rdev->flags);
                spin_unlock_irqrestore(&conf->device_lock, flags);
-               /*
-                * if recovery is running, make sure it aborts.
-                */
-               set_bit(MD_RECOVERY_INTR, &mddev->recovery);
        } else
                set_bit(Faulty, &rdev->flags);
+       /*
+        * if recovery is running, make sure it aborts.
+        */
+       set_bit(MD_RECOVERY_INTR, &mddev->recovery);
        set_bit(MD_CHANGE_DEVS, &mddev->flags);
        printk(KERN_ALERT
               "md/raid1:%s: Disk failure on %s, disabling device.\n"

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 353c2b3926521751b8cf9517356b7416fdd09012..a1ea2a75391240548b5283c74dd8314745d9649d 100644 (file)
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1681,11 +1681,11 @@ static void error(struct mddev *mddev, struct md_rdev *rdev)
                spin_lock_irqsave(&conf->device_lock, flags);
                mddev->degraded++;
                spin_unlock_irqrestore(&conf->device_lock, flags);
-               /*
-                * if recovery is running, make sure it aborts.
-                */
-               set_bit(MD_RECOVERY_INTR, &mddev->recovery);
        }
+       /*
+        * If recovery is running, make sure it aborts.
+        */
+       set_bit(MD_RECOVERY_INTR, &mddev->recovery);
        set_bit(Blocked, &rdev->flags);
        set_bit(Faulty, &rdev->flags);
        set_bit(MD_CHANGE_DEVS, &mddev->flags);