Re: [PATCH] s390x: pv: Fix diag318 PV fencing

[David Hildenbrand]

On 22.10.20 10:39, Janosch Frank wrote:
> On 10/22/20 10:32 AM, David Hildenbrand wrote:
>> On 22.10.20 10:23, Janosch Frank wrote:
>>> Diag318 fencing needs to be determined on the current VM PV state and
>>> not on the state that the VM has when we create the CPU model.
>>>
>>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>>> Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
>>> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
>>> Fixes: fabdada935 ("s390: guest support for diagnose 0x318")
>>> ---
>>>
>>> If you're sure that this is what you want, then I'll send a v2 of the
>>> patch set.
>>
>> So that's going to be the first CPU feature that gets suppressed in PC
>> mode - which seems to be what we want.
>>
>> diag318_needed() will return false, resulting in vmstate_diag318() not
>> being included in the migration stream (I know, we don't support
>> migration yet for PV).
> 
> Well either you have it and need to migrate it or you don't.
> As it doesn't persist over IPLs, that should not be a problem, no?

Okay, was confused by no finding a proper reset from our central reset
handler. So this feels like the right thing to do.


-- 
Thanks,

David / dhildenb