RE: [Intel-gfx] [ANNOUNCE][RFC] KVMGT - the implementation of Intel GVT-g(full GPU virtualization) for KVM

From: Tian, Kevin
Date: Mon Dec 08 2014 - 21:52:06 EST


> From: Daniel Vetter
> Sent: Monday, December 08, 2014 6:21 PM
>
> On Mon, Dec 08, 2014 at 10:55:01AM +0100, Gerd Hoffmann wrote:
> > On Sa, 2014-12-06 at 12:17 +0800, Jike Song wrote:
> > > I don't know that is exactly needed, we also need to have Windows
> > > driver considered. However, I'm quite confident that, if things gonna
> > > work for IGD passthrough, it gonna work for GVT-g.
> >
> > I'd suggest to focus on q35 emulation. q35 is new enough that a version
> > with integrated graphics exists, so the gap we have to close is *much*
> > smaller.
> >
> > In case guests expect a northbridge matching the chipset generation of
> > the graphics device (which I'd expect is the case, after digging a bit
> > in the igd and agpgart linux driver code) I think we should add proper
> > device emulation for them, i.e. comply q35-pcihost with
> > sandybridge-pcihost + ivybridge-pcihost + haswell-pcihost instead of
> > just copying over the pci ids from the host. Most likely all those
> > variants can share most of the emulation code.
>
> I don't think i915.ko should care about either northbridge nor pch on
> para-virtualized platforms. We do noodle around in there for the oddball
> memory controller setting and for some display stuff. But neither of that
> really applies to paravirtualized hw. And if there's any case like that we
> should patch it out (like we do with some of the runtime pm code
> already).

Agree. Now Allen is working on how to avoid those tricky platform
stickiness in Windows gfx driver. We should do same thing in Linux
part too.

Thanks
Kevin