On 23.02.21 10:48, Halil Pasic wrote:

On Mon, 15 Feb 2021 20:15:47 -0500
Tony Krowiak [off-list ref] wrote:

quoted

This patch fixes a circular locking dependency in the CI introduced by
commit f21916ec4826 ("s390/vfio-ap: clean up vfio_ap resources when KVM
pointer invalidated"). The lockdep only occurs when starting a Secure
Execution guest. Crypto virtualization (vfio_ap) is not yet supported for
SE guests; however, in order to avoid CI errors, this fix is being
provided.

The circular lockdep was introduced when the masks in the guest's APCB
were taken under the matrix_dev->lock. While the lock is definitely
needed to protect the setting/unsetting of the KVM pointer, it is not
necessarily critical for setting the masks, so this will not be done under
protection of the matrix_dev->lock.

With the one little thing I commented on below addressed: 
Acked-by: Halil Pasic <pasic@linux.ibm.com>  

Tony, can you comment on Halils comment or send a v3 right away?