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

[Parav Pandit <parav@nvidia.com>]

> From: virtio-comment@lists.oasis-open.org <virtio-comment@lists.oasis-
> open.org> On Behalf Of Jason Wang
> Sent: Thursday, October 19, 2023 10:15 AM
> 
> > > Again, if you don't want to talk about transport virtqueue, that's
> > > fine. But let's leave the scalability issue aside as well.
> > >
> > Registers are related for functionality and scale.
> >
> > Lets first agree on use case before the design, that I asked above.
> >
> > I will wait to respond to any other emails until we agree on use case
> requirements.
> 
> There are more than just me who want you to define "passthrough" first where
> you refuse to respond.
> 
Totally disagree.
In the previous email itself, I wrote what passthrough is.
So let's try yet one more time.
Either you can re-read last email or for better read below and see if it is understood or not.

> How could we make any agreement without an accurate the definition of
> "passthrough" who is a key to understand each other?

I replied few times in past emails but since those email threads are so long, it is easy to miss out.

Passthrough definition:
a. virtio member device mapped to the guest vm
b. only pci config space and msix of a member device is intercepted by hypervisor.
c. virtio config space, virtio cvqs, data vqs of a member device is directly accessed by the guest vm without intercepted by the hypervisor.

(Why b?, no grand reason, it is how the hypervisors are working where to integrate the virtio member device to).