On 26.06.19 16:30, Collin Walling wrote: > On 6/26/19 6:28 AM, Christian Borntraeger wrote: >> >> >> On 26.06.19 11:45, David Hildenbrand wrote: >> >>> >>> BTW. there is currently no mechanism to fake absence of diag318. Should >>> we have one? (in contrast, for CMMA we have, which is also a CPU feature) >> >> Yes, we want to be able to disable diag318 via a CPU model feature. That actually >> means that the kernel must not answer this if we disable it. >> > Correct. If the guest specifies diag318=off, then the instruction > shouldn't be executed (it is fenced off in the kernel by checking the > Read SCP Info bit). But the guest *could* execute it and not get an exception. -- Thanks, David / dhildenb