Re: [Qemu-devel] [PATCH v3] s390x/cpumodel: Set up CPU model for AQIC interception

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

On 15/02/2019 10:58, Christian Borntraeger wrote:
> 
> 
> On 15.02.2019 10:53, Pierre Morel wrote:
>> On 14/02/2019 13:14, Pierre Morel wrote:
>>> A new CPU model facilities is introduced to support AP devices
>>> interruption interception for a KVM guest.
>>>
>>> "APQI" for "AP-Queue Interruption" facility
>>>
>>> The S390_FEAT_AP_QUEUE_INTERRUPT_CONTROL, CPU facility indicates
>>> whether the PQAP instruction with the AQIC command is available
>>> to the guest.
>>> This feature will be enabled only if the AP instructions are
>>> available on the linux host and AQIC facility is installed on
>>> the host.
>>>
>>> This feature must be turned on from userspace to intercept AP
>>> instructions on the KVM guest. The QEMU command line to turn
>>> this feature on looks something like this:
>>>
>>>       qemu-system-s390x ... -cpu xxx,apqi=on ...
>>
>>
>>
>> Hi,
>>
>> I suddenly have a very big doubt on this QEMU patch.
>>
>> Older Linux advertise PQAP/AQIC feature (65)
> 
> Which Linuxes advertise PQAP/AQIC (stfle.65)?
> This was never advertised by any previous Linux as far as I can tell.
> 

OK, very sorry, you are right, I checked on a different machine and it 
is not.
I must have left something in my system.

Sorry for the panic.
I will look at what made me experience this.

Regards,
Pierre

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