md: raid1/raid10: fix problem with merge_bvec_fn
commit aba336bd1d46d6b0404b06f6915ed76150739057 upstream.
The new merge_bvec_fn which calls the corresponding function
in subsidiary devices requires that mddev->merge_check_needed
be set if any child has a merge_bvec_fn.
However were were only setting that when a device was hot-added,
not when a device was present from the start.
This bug was introduced in 3.4 so patch is suitable for 3.4.y
kernels. However that are conflicts in raid10.c so a separate
patch will be needed for 3.4.y.
Reported-by: Sebastian Riemer <sebastian.riemer@profitbricks.com>
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 15dd59b..d7e9577 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2548,6 +2548,7 @@
err = -EINVAL;
spin_lock_init(&conf->device_lock);
rdev_for_each(rdev, mddev) {
+ struct request_queue *q;
int disk_idx = rdev->raid_disk;
if (disk_idx >= mddev->raid_disks
|| disk_idx < 0)
@@ -2560,6 +2561,9 @@
if (disk->rdev)
goto abort;
disk->rdev = rdev;
+ q = bdev_get_queue(rdev->bdev);
+ if (q->merge_bvec_fn)
+ mddev->merge_check_needed = 1;
disk->head_position = 0;
}