Set passthrough GPU as a primary graphics card for a VM

[acebmxer]

I was able to get nvidia rtx 4070 passed through to a windows VM and Ubuntu server. Need to make sure you passing all the devices associated with the GPU, specifically the Audio controller on the GPU.

These were on AMD systems.

[miltador]

Good to see some successes here, no luck for me with Intel N100 iGPU though
Both Linux and Windows.

[kubuntu-newbie]

@acebmxer in my case it appears to be a Wayland issue, using the wrong card. I was hoping that I could disable virtual gpu all together

curious though that disabling virtual GPU just changes the device id in the vm from 1234:1111 to "cirrus" - that seems to be a bug in XCP-ng

[acebmxer]

@kubuntu-newbie

Yeah i didnt do anything with disabling the vgpu. Just a standard Win 11 or ubuntu VM and attached the nivdia gpu.

[olivierlambert]

IIRC, Intel iGPU is very different than a discrete GPU from a system perspective, that might explain your problem.

[kubuntu-newbie]

@olivierlambert
it is still not clear to me how changing vga: std to vga: cirrus in platform parameter of a vm constitute turning off vga (this is what happens when you turn off vga in Xen Orchestra)

manually setting vga to off in platform produces the same result as vga: cirrus, VM still sees "VGA compatible controller [0300]: Cirrus Logic GD 5446 [1013:00b8]"

is there a way to completely turn off creating this virtual VGA in the VM?

[kubuntu-newbie]

@olivierlambert

and removing key vga from platform all together has the same result as switching to cirrus, there is still a virtual vga Cirrus Logic in the VM

[olivierlambert]

Because it's the default you cannot bypass. @Team-XAPI-Network could confirm

[kubuntu-newbie]

@olivierlambert

thank you! I did a little digging, but I could be looking at the wrong place, according to:

https://github.com/xcp-ng/qemu-dp/blob/master/qemu-options.hx

there is an option vga: none

DEF("vga", HAS_ARG, QEMU_OPTION_vga,
"-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
" select video card type\n", QEMU_ARCH_ALL)
SRST
-vga type
...
none
Disable VGA card.

I tried setting this manually via "xe vm-param-set platform:vga=none " and I still get Cirrus PCI device created in the VM

Is there something else that needs to be done to have no virtual VGA in the VM at all?

[psafont]

@kubuntu-newbie I've looked at the code. The intel passthrough seems to not care about the value of the vga key in platform, and instead it expects the key igd_passthrough to be set to true.

https://github.com/xapi-project/xen-api/blob/9eb5f9f9f3c742c0c0b691098e1dafc02e40c856/ocaml/xapi/xapi_xenops.ml#L390