[PATCH v7 5/8] loop: be paranoid on exit and prevent new additions / removals
From: Luis Chamberlain <mcgrof@kernel.org>
Date: 2020-06-19 20:48:11
Also in:
linux-fsdevel, linux-mm, lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
Be pedantic on removal as well and hold the mutex. This should prevent uses of addition while we exit. Reviewed-by: Ming Lei <redacted> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> --- drivers/block/loop.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index c33bbbfd1bd9..d55e1b52f076 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c@@ -2402,6 +2402,8 @@ static void __exit loop_exit(void) range = max_loop ? max_loop << part_shift : 1UL << MINORBITS; + mutex_lock(&loop_ctl_mutex); + idr_for_each(&loop_index_idr, &loop_exit_cb, NULL); idr_destroy(&loop_index_idr);
@@ -2409,6 +2411,8 @@ static void __exit loop_exit(void) unregister_blkdev(LOOP_MAJOR, "loop"); misc_deregister(&loop_misc); + + mutex_unlock(&loop_ctl_mutex); } module_init(loop_init);
--
2.26.2