Re: VFIO Migration

[Michael S. Tsirkin]

On Thu, Nov 05, 2020 at 11:40:37AM +0000, Stefan Hajnoczi wrote:
> On Wed, Nov 04, 2020 at 05:32:02PM +0000, Dr. David Alan Gilbert wrote:
> > * Stefan Hajnoczi (stefanha@redhat.com) wrote:
> > > Michael replied in another sub-thread wondering if versions are really
> > > necessary since tools do the migration checks. Let's try dropping
> > > versions to simplify things. We can bring them back if needed later.
> > 
> > What does a user facing tool do?  If I say I want one of these NICs
> > and I'm on the latest QEMU machine type, who sets all these parameters?
> 
> The machine type is orthogonal since QEMU doesn't know about every
> possible VFIO device. The device is like a PCI adapter that is added to
> a physical machine aftermarket, it's not part of the base machine's
> specs.

I think at least at the first stage, it is a smart thing to do
to have a list of allowed devices in QEMU. This way we can ask
for a spec of the migration format, include it in qemu
(or a subtree? I don't mind ...) and check it is sane.
And we can be reasonably sure we can make changes
without breaking the world - we will know whom to
contact if we change the protocol.

-- 
MST