commit 
99994cd btrfs: dev delete should remove sysfs entry
added a btrfs_kobj_rm_device, which dereferences device->bdev...
right after we check whether device->bdev might be NULL.
I don't honestly know if it's possible to have a NULL device->bdev
here, but assuming that it is (given the test), we need to move
the kobject removal to be under that test.
(Coverity spotted this)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
        if (device->bdev == root->fs_info->fs_devices->latest_bdev)
                root->fs_info->fs_devices->latest_bdev = next_device->bdev;
 
-       if (device->bdev)
+       if (device->bdev) {
                device->fs_devices->open_devices--;
-
-       /* remove sysfs entry */
-       btrfs_kobj_rm_device(root->fs_info, device);
+               /* remove sysfs entry */
+               btrfs_kobj_rm_device(root->fs_info, device);
+       }
 
        call_rcu(&device->rcu, free_device);