md: handle writes to broken raid10 arrays gracefully
When writing to a broken array, raid10 currently happily emits empty bio
lists. IOW, the master bio will never be completed, sending writers to
UNINTERRUPTIBLE_SLEEP forever.
Signed-off-by: Arne Redlich <agr@powerkom-dd.de>
Acked-by: Neil Brown <neilb@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 0c97bf4..4e53792 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -917,6 +917,13 @@
bio_list_add(&bl, mbio);
}
+ if (unlikely(!atomic_read(&r10_bio->remaining))) {
+ /* the array is dead */
+ md_write_end(mddev);
+ raid_end_bio_io(r10_bio);
+ return 0;
+ }
+
bitmap_startwrite(mddev->bitmap, bio->bi_sector, r10_bio->sectors, 0);
spin_lock_irqsave(&conf->device_lock, flags);
bio_list_merge(&conf->pending_bio_list, &bl);