On Thu, Jul 15, 2021 at 08:11:57AM +0100, Christoph Hellwig wrote:

On Wed, Jul 14, 2021 at 09:55:31PM -0700, Luis Chamberlain wrote:

quoted

Now that error handling for add_disk*() calls is added, we must
accept a common form for when errors are detected on the the
add_disk*() calls, and that is to call blk_cleanup_disk() on
error always. One of the corner cases possible is a driver bug
where the queue is already gone and we cannot blk_get_queue(),
and so may be NULL. When blk_cleanup_disk() is called in this
case blk_cleanup_queue() will crash with a null dereference.

Make this an accepted condition and just skip it. This allows us
to also test for it safely with error injection.

So you plan to call blk_cleanup_disk when add_disk fails?

Yes, they can open code things if they wish as well, but when possible yes.

For all drivers using blk_alloc_disk/blk_mq_alloc_disk there should
always be a queue.  The others ones aren't ready to handle errors
from add_disk yet in any way I think (and I plan to fix this up
ASAP).

Have an example in mind?

  Luis