Commit e91455ba authored Aug 07, 2019 by Jan Kara Committed by Jens Axboe Aug 08, 2019

bdev: Fixup error handling in blkdev_get()



Commit 89e524c0 ("loop: Fix mount(2) failure due to race with
LOOP_SET_FD") converted blkdev_get() to use the new helpers for
finishing claiming of a block device. However the conversion botched the
error handling in blkdev_get() and thus the bdev has been marked as held
even in case __blkdev_get() returned error. This led to occasional
warnings with block/001 test from blktests like:

kernel: WARNING: CPU: 5 PID: 907 at fs/block_dev.c:1899 __blkdev_put+0x396/0x3a0

Correct the error handling.

CC: stable@vger.kernel.org
Fixes: 89e524c0 ("loop: Fix mount(2) failure due to race with LOOP_SET_FD")
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent fd03177c

fs/block_dev.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1750,7 +1750,10 @@ int blkdev_get(struct block_device bdev, fmode_t mode, void holder)

		/* finish claiming */
		mutex_lock(&bdev->bd_mutex);
		if (!res)
		bd_finish_claiming(bdev, whole, holder);
		else
		bd_abort_claiming(bdev, whole, holder);
		/*
		* Block event polling for write claims if requested. Any
		* write holder makes the write_holder state stick until

Admin message