libvirt users - Aug 2020 - Re: pass-though Intel gpu int o a vm

Greetings,

I have a server that run a vm with several nic pcie cards as pass-though.
the board has an intel gpu and the hdmi output is not used.
I thought of booting up another vm and pass the gpu into it.
I found several discussions on the subject stating that it isn't possible
but all of them are several years old.
I wonder if that has changed? is there a way to pt the vga to a vm?

Thanks,

Dagg.

On Sat, Aug 08, 2020 at 06:44:26PM +0200, daggs wrote:
> Greetings,
>
> I have a server that run a vm with several nic pcie cards as pass-though.
> the board has an intel gpu and the hdmi output is not used.
> I thought of booting up another vm and pass the gpu into it.
> I found several discussions on the subject stating that it isn't
possible but all of them are several years old.
> I wonder if that has changed? is there a way to pt the vga to a vm?
>
> Thanks,
>
> Dagg.
>
Hi,
libvirt has supported host device assignment for quite some time, so from that
perspective, you can follow [1] and see if your card works in the VM. The GPU
assignment involves the userspace VFIO driver and there are a few factors in
play which may render the assignment either not work at all or work with
limitations. In any case, this question would be better asked at
vfio-users@redhat.com mailing list should you experience any issues with [1].

Regards,
Erik

[1] https://libvirt.org/formatdomain.html#host-device-assignment

PS: You can even try assigning the GPU from within virt-manager which produces
the right XML bits for libvirt. I've never tried assigning an integrated
Intel
GPU on my laptop (for obvious reasons), so I can't give you the kind of
answer
guaranteeing this would work 100%.

Greetings Erik,
> Sent: Tuesday, August 11, 2020 at 10:11 AM
> From: "Erik Skultety" <eskultet@redhat.com>
> To: "daggs" <daggs@gmx.com>
> Cc: libvirt-users@redhat.com
> Subject: Re: pass-though Intel gpu int o a vm
>
> On Sat, Aug 08, 2020 at 06:44:26PM +0200, daggs wrote:
> > Greetings,
> >
> > I have a server that run a vm with several nic pcie cards as
pass-though.
> > the board has an intel gpu and the hdmi output is not used.
> > I thought of booting up another vm and pass the gpu into it.
> > I found several discussions on the subject stating that it isn't
possible but all of them are several years old.
> > I wonder if that has changed? is there a way to pt the vga to a vm?
> >
> > Thanks,
> >
> > Dagg.
> >
>
> Hi,
> libvirt has supported host device assignment for quite some time, so from
that
> perspective, you can follow [1] and see if your card works in the VM. The
GPU
> assignment involves the userspace VFIO driver and there are a few factors
in
> play which may render the assignment either not work at all or work with
> limitations. In any case, this question would be better asked at
> vfio-users@redhat.com mailing list should you experience any issues with
[1].
I'll try ask them, thanks.
>
> Regards,
> Erik
>
> [1] https://libvirt.org/formatdomain.html#host-device-assignment
>
> PS: You can even try assigning the GPU from within virt-manager which
produces
> the right XML bits for libvirt. I've never tried assigning an
integrated Intel
> GPU on my laptop (for obvious reasons), so I can't give you the kind of
answer
> guaranteeing this would work 100%.
>
>
the system in question is a headless server so virt-manager is nto an option.
thanks for the suggestion thought.

Dagg.