Re: [PATCH v1] KVM: s390: use defines for execution controls

From: David Hildenbrand
Date: Tue Mar 14 2017 - 09:55:13 EST


Am 14.03.2017 um 14:51 schrieb Christian Borntraeger:
> On 03/13/2017 11:48 AM, David Hildenbrand wrote:
>> Let's replace the bitmasks by defines. Reconstructed from code, comments
>> and commit messages.
>>
>> Tried to keep the defines short and map them to feature names. In case
>> they don't completely map to features, keep them in the stye of ICTL
>> defines.
>>
>> This effectively drops all "U" from the existing numbers. I think this
>> should be fine (as similarly done for e.g. ICTL defines).
>
> The patch does change the binary result and this seems to be related to the
> U removal. But as far as I can tell this is fine, its just some subtle
> undefined behaviour change between unsigned/signed which we do not care
> about.
>
>
>>
>> I am not 100% sure about the ECA_MVPGI and ECA_PROTEXCI bits as they are
>> always used in pairs.
>
> Just historic baggage, e.g. in 3.10 we set eca to 0xC1002001 and over
> time we split those out piece by piece. Those two are just the last men
> standing.
>
> I think I am going to apply this with some minor changes (EC* names). Ok
> when I do the changes?
>

Sure, feel free to modify!

Thanks!

--
Thanks,

David