Re: [RFC PATCH 0/4] Implement multiqueue virtio-net

Krishna Kumar2
2010-09-09T13:19:26Z

Arnd Bergmann <arnd@arndb.de> wrote on 09/09/2010 04:10:27 PM:

> > > Can you live migrate a new guest from new-qemu/new-kernel
> > > to old-qemu/old-kernel, new-qemu/old-kernel and old-qemu/new-kernel?
> > > If not, do we need to support all those cases?
> >
> > I have not tried this, though I added some minimal code in
> > virtio_net_load and virtio_net_save. I don't know what needs
> > to be done exactly at this time. I forgot to put this in the
> > "Next steps" list of things to do.
>
> I was mostly trying to find out if you think it should work
> or if there are specific reasons why it would not.
> E.g. when migrating to a machine that has an old qemu, the guest
> gets reduced to a single queue, but it's not clear to me how
> it can learn about this, or if it can get hidden by the outbound
> qemu.

I agree, I am also not sure how the old guest will handle this.
Sorry about my ignorance on migration :(

Regards,

- KK