RE: [virtio-comment] [PATCH v1 1/8] admin: Add theory of operation for device migration

[Parav Pandit <parav@nvidia.com>]

> From: Michael S. Tsirkin <mst@redhat.com>
> Sent: Friday, November 24, 2023 5:40 PM
> 
> On Fri, Nov 24, 2023 at 07:51:06PM +0800, Jason Wang wrote:
> > On Fri, Nov 24, 2023 at 7:38âPM Michael S. Tsirkin <mst@redhat.com>
> wrote:
> > >
> > > On Fri, Nov 24, 2023 at 11:07:53AM +0800, Jason Wang wrote:
> > > > How TDISP/attestation is related to a specific device driver? How
> > > > can a legacy DPDK driver break things like attestation here?
> > > >
> > > > > Hence it is not applicable.
> > > >
> > > > Wow. The legacy tunnel was just invented by you for just several
> > > > months and soon became a second-class citizen in the proposal here?
> > >
> > > Legacy is not going to be a 1st class citizen and that was a
> > > concious decision the TC made.
> > > In particular we know straight
> > > away that there is no way to make them safely work while preserving
> > > assumptions confidential computing guests make (which I guess is
> > > what you mean here).
> >
> > Probably, but I think we need to support its migration without TD.
> 
> Ah, migration of legacy guests is an interesting point.
> Bringing up TD was just confusing.
> 
> I expect this to be rather painless to add precisely because this proposal does
> not reply on either modern or legacy pci layout. But details need to be
> thought through, I agree. I don't see why this is not applicable - definitely
> people are used to be able to migrate these guests.
>
The current layout in device context is for the modern.
The legacy one will be just another enum and struct that will be added subsequently.
 
> 
> > > The whole point of isolating legacy mess in the special commands was
> > > so we don't try to support them going forward, don't try to add new
> > > features for legacy interfaces please.
> >
> > Thanks
> >
> >
> > >
> > > --
> > > MST
> > >