4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche <bart.vanassche@xxxxxxx> commit 5a0ec388ef0f6e33841aeb810d7fa23f049ec4cd upstream. Commit 523e1d399ce0 ("block: make gendisk hold a reference to its queue") modified add_disk() and disk_release() but did not update any of the error paths that trigger a put_disk() call after disk->queue has been assigned. That introduced the following behavior in the pktcdvd driver if pkt_new_dev() fails: Kernel BUG at 00000000e98fd882 [verbose debug info unavailable] Since disk_release() calls blk_put_queue() anyway if disk->queue != NULL, fix this by removing the blk_cleanup_queue() call from the pkt_setup_dev() error path. Fixes: commit 523e1d399ce0 ("block: make gendisk hold a reference to its queue") Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Cc: Maciej S. Szmigiero <mail@xxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/block/pktcdvd.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -2779,7 +2779,7 @@ static int pkt_setup_dev(dev_t dev, dev_ pd->pkt_dev = MKDEV(pktdev_major, idx); ret = pkt_new_dev(pd, dev); if (ret) - goto out_new_dev; + goto out_mem2; /* inherit events of the host device */ disk->events = pd->bdev->bd_disk->events; @@ -2797,8 +2797,6 @@ static int pkt_setup_dev(dev_t dev, dev_ mutex_unlock(&ctl_mutex); return 0; -out_new_dev: - blk_cleanup_queue(disk->queue); out_mem2: put_disk(disk); out_mem: