Re: [PATCH v2] s390: vsie: Use effective CRYCBD.31 to check CRYCBD validity

[Pierre Morel <pmorel@linux.ibm.com>]

On 11/02/2019 10:47, Cornelia Huck wrote:
> On Mon, 11 Feb 2019 10:20:49 +0100
> Pierre Morel <pmorel@linux.ibm.com> wrote:
> 
>> When facility.76 MSAX3 is present for the guest we must issue a validity
>> interception if the CRYCBD is not valid.
>>
>> The bit CRYCBD.31 is an effective field and tested at each guest
>> level and has for effect to mask the facility.76
>>
>> It follows that if CRYCBD.31 is clear and AP is not in use  we do not
>> have to test the CRYCBD validatity even facility.76 is present in the
> 
> s/even/even if/

yes

> 
>> host.
>>
>> Fixes: 6ee74098201b ("KVM: s390: vsie: allow CRYCB FORMAT-0")
>> Cc: stable@vger.kernel.org
>>
>> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
>> Reported-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
>> Acked-by: David Hildenbrand <david@redhat.com>
>> ---
>>   arch/s390/kvm/vsie.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
>> index a153257..d62fa14 100644
>> --- a/arch/s390/kvm/vsie.c
>> +++ b/arch/s390/kvm/vsie.c
>> @@ -297,7 +297,7 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
>>   	scb_s->crycbd = 0;
>>   
>>   	apie_h = vcpu->arch.sie_block->eca & ECA_APIE;
>> -	if (!apie_h && !key_msk)
>> +	if (!apie_h && (!key_msk || fmt_o == CRYCB_FORMAT0))
>>   		return 0;
>>   
>>   	if (!crycb_addr)
> 
> Acked-by: Cornelia Huck <cohuck@redhat.com>
> 

Thanks Pierre

-- 
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany