Commit a514379b authored Feb 11, 2016 by Matias Bjørling Committed by Jens Axboe Feb 11, 2016

null_blk: oops when initializing without lightnvm



If the LightNVM subsystem is not compiled into the kernel, and the
null_blk device driver requests lightnvm to be initialized. The call to
nvm_register fails and the null_add_dev function cleans up the
initialization. However, at this point the null block device has
already been added to the nullb_list and thus a second cleanup will
occur when the function has returned, that leads to a double call to
blk_cleanup_queue.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

parent 39a169b6

drivers/block/null_blk.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -707,9 +707,7 @@ static int null_add_dev(void)
		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, nullb->q);
		queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, nullb->q);


		mutex_lock(&lock);
		list_add_tail(&nullb->list, &nullb_list);
		nullb->index = nullb_indexes++;
		mutex_unlock(&lock);

		@@ -743,6 +741,10 @@ static int null_add_dev(void)
		strncpy(disk->disk_name, nullb->disk_name, DISK_NAME_LEN);

		add_disk(disk);

		mutex_lock(&lock);
		list_add_tail(&nullb->list, &nullb_list);
		mutex_unlock(&lock);
		done:
		return 0;