Re: [Qemu-devel] [PULL 37/40] s390x/kvm: Enable KSS facility for nested virtualization

[Christian Borntraeger <borntraeger@de.ibm.com>]

On 07/17/2017 07:35 PM, David Hildenbrand wrote:
> On 14.07.2017 12:41, Christian Borntraeger wrote:
>> From: Farhan Ali <alifm@linux.vnet.ibm.com>
>>
>> If the host supports keyless subset (KSS) then first level
>> guest (G2) should enable KSS facility as well.
>>
>> Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
>> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
>> Acked-by: Cornelia Huck <cohuck@redhat.com>
>> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
>> ---
>>  target/s390x/kvm.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
>> index 8c6cc0a..c773bd6 100644
>> --- a/target/s390x/kvm.c
>> +++ b/target/s390x/kvm.c
>> @@ -2508,6 +2508,7 @@ static int kvm_to_feat[][2] = {
>>      { KVM_S390_VM_CPU_FEAT_CMMA, S390_FEAT_SIE_CMMA },
>>      { KVM_S390_VM_CPU_FEAT_PFMFI, S390_FEAT_SIE_PFMFI},
>>      { KVM_S390_VM_CPU_FEAT_SIGPIF, S390_FEAT_SIE_SIGPIF},
>> +    { KVM_S390_VM_CPU_FEAT_KSS, S390_FEAT_SIE_KSS},
>>  };
>>  
>>  static int query_cpu_feat(S390FeatBitmap features)
>>
> 
> This bit is not part of any cpu model, so how is this helpful?
> (AFAIK it will simply be dropped from the host model)

See the new patch for z14. ( i had to defer that part till
todays announcement)