Re: device compatibility interface for live migration with assigned devices

[Cornelia Huck]

On Tue, 18 Aug 2020 09:55:27 +0100
Daniel P. Berrangé <berrange@redhat.com> wrote:

> On Tue, Aug 18, 2020 at 11:24:30AM +0800, Jason Wang wrote:
> > Another point, as we discussed in another thread, it's really hard to make
> > sure the above API work for all types of devices and frameworks. So having a
> > vendor specific API looks much better.  
> 
> From the POV of userspace mgmt apps doing device compat checking / migration,
> we certainly do NOT want to use different vendor specific APIs. We want to
> have an API that can be used / controlled in a standard manner across vendors.

As we certainly will need to have different things to check for
different device types and vendor drivers, would it still be fine to
have differing (say) attributes, as long as they are presented (and can
be discovered) in a standardized way?

(See e.g. what I came up with for vfio-ccw in a different branch of
this thread.)

E.g.
version=
<type>.type_specific_value0=
<type>.type_specific_value1=
<vendor_driver>.vendor_driver_specific_value0=

with a type or vendor driver having some kind of
get_supported_attributes method?