Re: [PATCH v9 22/22] s390: doc: detailed specifications for AP virtualization

[Harald Freudenberger]

... about control domains

Talked with the s390 firmware guys. The convention that the control domain
mask is a superset of the usage domain mask is only true for 1st level guests.

It is absolutely valid to run a kvm guest with restricted control domain
mask bitmap in the CRYCB. It is valid to have an empty control domain mask
and the guest should be able to run crypto CPRBs on the usage domain(s) without
any problems. However, nobody has tried this.

regards
Harald Freudenberger