Re: [Qemu-devel] [Xen-devel] [RFC QEMU PATCH v3 00/10] Implement vNVDIMM for Xen HVM guest

[Konrad Rzeszutek Wilk]

On Sun, Oct 15, 2017 at 03:31:15AM +0300, Michael S. Tsirkin wrote:
> On Fri, Oct 13, 2017 at 03:46:39PM -0700, Stefano Stabellini wrote:
> > On Fri, 13 Oct 2017, Jan Beulich wrote:
> > > >>> On 13.10.17 at 13:13, <address@hidden> wrote:
> > > > To Jan, Andrew, Stefano and Anthony,
> > > > 
> > > > what do you think about allowing QEMU to build the entire guest ACPI
> > > > and letting SeaBIOS to load it? ACPI builder code in hvmloader is
> > > > still there and just bypassed in this case.
> > > 
> > > Well, if that can be made work in a non-quirky way and without
> > > loss of functionality, I'd probably be fine. I do think, however,
> > > that there's a reason this is being handled in hvmloader right now.
> > 
> > And not to discourage you, just as a clarification, you'll also need to
> > consider backward compatibility: unless the tables are identical, I
> > imagine we'll have to keep using the old tables for already installed
> > virtual machines.
> 
> Maybe you can handle this using machine type versioning.

<nods> And the type could be v2 if nvdimm was provided (which is
something that the toolstack would figure out).

The toolstack could also have a seperate 'v2' config flag if somebody
wanted to play with this _outside_ of having NVDIMM in the guest?


> Installed guests would use the old type.

<nods>