virtio_blk: fix race at module removal
If a device appears while module is being removed,
driver will get a callback after we've given up
on the major number.
In theory this means this major number can get reused
by something else, resulting in a conflict.
To fix, cleanup in reverse order of initialization.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index c6a27d5..ce848ac 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -871,8 +871,8 @@
static void __exit fini(void)
{
- unregister_blkdev(major, "virtblk");
unregister_virtio_driver(&virtio_blk);
+ unregister_blkdev(major, "virtblk");
destroy_workqueue(virtblk_wq);
}
module_init(init);