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

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Oct 19, 2023 at 05:53:29AM -0400, Michael S. Tsirkin wrote:
> On Thu, Oct 19, 2023 at 09:41:46AM +0000, Parav Pandit wrote:
> > 
> > > From: Michael S. Tsirkin <mst@redhat.com>
> > > Sent: Thursday, October 19, 2023 3:03 PM
> > > > > > With a capability you can discover it without poking at features.
> > > > > >
> > > > > It is discouraged by pci spec.
> > > > > Pci caps for mostly doing very small init time sort of config.
> > > > > Not to run frequent commands.
> > > >
> > > > Interesting. where in the spec exactly?
> > > 
> > > And the reason I ask is because I'd like to understand the exact limitation.
> > > 
> > > In any case, we should still maybe look for ways to separate it from config.
> > > Maybe a capability points at a BAR and that is where we have this stuff?
> > > 
> > Yes, I replied in your previous email, a similar suggestion.
> > Lets first agree that it is drafted for non-passthrough mode.
> 
> I could see passthrough use it too if there, why not.

The big limitation of such a hack is dependence on PASID.
So it's more of a long term option when PASID becomes more
widespread.

-- 
MST