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Subject: Re: [PATCH v9 12/22] s390: vfio-ap: sysfs interfaces to configure
 control domains
To:     Cornelia Huck <cohuck@redhat.com>
Cc:     Tony Krowiak <akrowiak@linux.ibm.com>,
        Halil Pasic <pasic@linux.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
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From:   Pierre Morel <pmorel@linux.ibm.com>
Date:   Thu, 23 Aug 2018 13:44:40 +0200
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On 23/08/2018 13:31, Cornelia Huck wrote:
> On Thu, 23 Aug 2018 12:43:42 +0200
> Pierre Morel <pmorel@linux.ibm.com> wrote:
> 
>> On 23/08/2018 12:25, Cornelia Huck wrote:
>>> On Wed, 22 Aug 2018 15:16:19 -0400
>>> Tony Krowiak <akrowiak@linux.ibm.com> wrote:
>>>    
>>>> One of the things I suggested in a private conversation with Christian
>>>> earlier
>>>> today was to provide an additional rw sysfs attribute - a boolean - that
>>>> indicates
>>>> whether all usage domains should also be control domains. The default
>>>> could be
>>>> true. This would allow one to configure guests with usage-only domains
>>>> as well
>>>> as satisfy the convention.
>>>
>>> Would this additional attribute then control "add usage domains to the
>>> list of control domains automatically", or "don't allow to add a usage
>>> domain if it has not already been added as a control domain"?
>>>
>>> One thing I'm still unsure about is how libvirt comes into the picture
>>> here. Will it consume the setting, or actively manipulate it?
>>>
>>> [In general, I'm not very clear about how libvirt will interact with the
>>> whole infrastructure...]
>>>    
>>
>> When I read you it convince me that it is not wise to change anything
>> that has been already discuss and could impact the Libvirt.
> 
> My main point basically was that we should get feedback from a libvirt
> POV :) The new attribute may make sense, or not; but I'm really feeling
> a bit in the dark with regard to libvirt.
> 

Me too, this explains my conservative approach ;)


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