block: Make del_gendisk() safer for disks without queues
authorJan Kara <jack@suse.cz>
Wed, 8 Mar 2017 16:48:33 +0000 (17:48 +0100)
committerJens Axboe <axboe@fb.com>
Wed, 8 Mar 2017 17:55:17 +0000 (10:55 -0700)
commit90f16fddcc2802726142b8386c65ccb89f044613
treeda1c8d56ab62dd362dc94fab542ba43a5144f67d
parentdf23de55615fa7a190a85f49a950ccecdd9102f3
block: Make del_gendisk() safer for disks without queues

Commit 165a5e22fafb "block: Move bdi_unregister() to del_gendisk()"
added disk->queue dereference to del_gendisk(). Although del_gendisk()
is not supposed to be called without disk->queue valid and
blk_unregister_queue() warns in that case, this change will make it oops
instead. Return to the old more robust behavior of just warning when
del_gendisk() gets called for gendisk with disk->queue being NULL.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Tested-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
block/genhd.c