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

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>
Cc: stable@vger.kernel.org

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 56e24c072b629324ec382037ab17fd43310ec3ef..d7690f86fdb9a6202edfa6d8fa5f95517fe8e75b 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1501,12 +1501,12 @@ 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 cb882aae9e20d4f7032a400884f45f50de57528f..b08c18871323c904f3964e9c8b650366ad2979ef 100644 (file)
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1684,13 +1684,12 @@ static void error(struct mddev *mddev, struct md_rdev *rdev)
                spin_unlock_irqrestore(&conf->device_lock, flags);
                return;
        }
-       if (test_and_clear_bit(In_sync, &rdev->flags)) {
+       if (test_and_clear_bit(In_sync, &rdev->flags))
                mddev->degraded++;
-                       /*
-                * 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);