loop: reorder loop_exit

Unregister the misc and blockdevice first to prevent further access,
and only then iterate to remove the devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210623145908.92973-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index cc0e8c3..0e96f8c 100644 (file)
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -2550,14 +2550,11 @@ static int loop_exit_cb(int id, void *ptr, void *data)
 static void __exit loop_exit(void)
 {
        mutex_lock(&loop_ctl_mutex);
-
-       idr_for_each(&loop_index_idr, &loop_exit_cb, NULL);
-       idr_destroy(&loop_index_idr);
-
        unregister_blkdev(LOOP_MAJOR, "loop");
-
        misc_deregister(&loop_misc);
 
+       idr_for_each(&loop_index_idr, &loop_exit_cb, NULL);
+       idr_destroy(&loop_index_idr);
        mutex_unlock(&loop_ctl_mutex);
 }