summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorNeilBrown <neilb@suse.de>2012-04-12 10:05:06 +0400
committerNeilBrown <neilb@suse.de>2012-04-12 10:05:06 +0400
commitafbaa90b80b1ec66e5137cc3824746bfdf559b18 (patch)
tree8c0307e41849eef28146343efc4fed75f83a30f1
parentf4380a915823dbed0bf8e3cf502ebcf2b7c7f833 (diff)
downloadlinux-afbaa90b80b1ec66e5137cc3824746bfdf559b18.tar.xz
md/bitmap: prevent bitmap_daemon_work running while initialising bitmap
If a bitmap is added while the array is active, it is possible for bitmap_daemon_work to run while the bitmap is being initialised. This is particularly a problem if bitmap_daemon_work sees bitmap->filemap as non-NULL before it has been filled in properly. So hold bitmap_info.mutex while filling in ->filemap to prevent problems. This patch is suitable for any -stable kernel, though it might not apply cleanly before about 3.1. Cc: stable@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
-rw-r--r--drivers/md/bitmap.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 1c264a701e70..97e73e555d11 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1785,7 +1785,9 @@ int bitmap_load(struct mddev *mddev)
* re-add of a missing device */
start = mddev->recovery_cp;
+ mutex_lock(&mddev->bitmap_info.mutex);
err = bitmap_init_from_disk(bitmap, start);
+ mutex_unlock(&mddev->bitmap_info.mutex);
if (err)
goto out;