When commit 
69e51b449d383e (md/bitmap:  separate out loading a bitmap...)
created bitmap_load, it missed calling it after bitmap_create when a
bitmap is created through the sysfs interface.
So if a bitmap is added this way, we don't allocate memory properly
and can crash.
This is suitable for any -stable release since 2.6.35.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
                        if (mddev->pers) {
                                mddev->pers->quiesce(mddev, 1);
                                rv = bitmap_create(mddev);
+                               if (!rv)
+                                       rv = bitmap_load(mddev);
                                if (rv) {
                                        bitmap_destroy(mddev);
                                        mddev->bitmap_info.offset = 0;