Re: [RFC] kvm tools: Add support for virtio-mmio

[Sasha Levin <levinsasha928@gmail.com>]

On Wed, 2011-11-16 at 13:21 +0000, Pawel Moll wrote:
> On Tue, 2011-11-15 at 17:56 +0000, Sasha Levin wrote:
> > Hmm... If thats the plan, it should probably be a virtio thing (not
> > virtio-mmio specific).
> > 
> > Either way, it could also use some clarification in the spec.
> 
> Well, the spec (p. 2.1) says: "The Subsystem Vendor ID should reflect
> the PCI Vendor ID of the environment (it's currently only used for
> informational purposes by the guest).". The fact is that all the current
> virtio drivers simply ignore this field. So unless this changes I simply
> have no idea how to describe that register. "Put anything there, no one
> cares"? "Write zero now, may change in future"? Any ideas welcomed.
> 
> Cheers!
> 
> Paweł
> 
> PS. Thanks for defending my honour in the delayed-explosive-device
> thread ;-)

We can add an appendix to the virtio spec with known virtio subsystem
vendors, patch QEMU & KVM tool to pass that, and possibly modify the
QEMU related workarounds in the kernel to only do the workaround thing
if QEMU is set as the vendor.

-- 

Sasha.