Re: [Xen-devel] vga passthrough with qemu-xen (or qemu upstream)

[Gordan Bobic <gordan@xxxxxxxxxx>]

On 2014-01-21 17:36, Shakeel Butt wrote:
> On Tue, Jan 21, 2014 at 4:55 AM, Pasi KÃrkkÃinen <pasik@xxxxxx> wrote:
> > Hello,
> >
> > On Mon, Jan 20, 2014 at 01:24:23PM +0000, Wu, Feng wrote:
> > > > >>> >
> > > > >>> > Hi all,
> > > > >>> >
> > > > >>> > Is it possible to do vga passthrough on xen-unstable with qemu-xen as
> > > > >>> > device model? I tried but I am getting error 'gfx_passthru' invalid
> > > > >>> > parameter for qemu-xen. I am able to do passthrough with qemu
> > > > >>> > traditional i.e. qemu-dm.
> > > > >>>
> > > > >>> As far as I know, only qemu-traditional supports vga pass-through
> > > > >>> right now.
> > > > >>
> > > > >> Right.
> > > > >> It is not possible to assign your primary VGA card to a VM with
> > > > >> qemu-xen. You should be able to assign your secondary VGA card though.
> > > > >
> > > > > Let me understand this correctly. If I have two VGA cards then I can
> > > > > passthrough
> > > > > secondary VGA card (in Dom0) to HVM as its primary VGA card. Is this
> > > > > right and
> > > > > if yes how can I do it?
> > > >
> > > > Passing any VGA card as a primary-in-domU has always been problematic.
> > >
> > > I think passing VGA card as a primary-in-domU works well in 
> > > Qemu-traditional, right?
> > primary-in-domU requires vendor specific hacks in Xen qemu.
> > qemu-traditional includes many patches for Intel IGD primary passthru 
> > support,
> > but patches for AMD/ATI and Nvidia GPUs aren't merged to 
> > qemu-traditional.
> > There unapplied patches for qemu-traditional (AMD/Nvidia) GPU passthru 
> > are in
> > various source trees, mailinglist archives, and on some blogs around 
> > the internet.
> > Also for Intel IGD I think there's at least one outstanding patch/fix 
> > that
> > hasn't been merged to qemu-traditional yet, see:
> >
> > http://lists.xenproject.org/archives/html/xen-devel/2013-02/msg00538.html
> > http://lists.xen.org/archives/html/xen-devel/2013-07/msg01385.html
> >
> > The patch in question probably needs some work before it is suitable 
> > for being applied to qemu-traditional.
> Thanks for sharing. Just for the information, I was able to make
> Nvidia K2000 work
> in passthrough mode without any patch to qemu traditional.
All Quadro x000 and Kx000 cards, both genuine and modified GeForces
are known to work fine with VGA passthrough.

Gordan

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel