IGVT-g

Intel GVT-g is a full GPU virtualization solution with mediated pass-through which allows host and multiple guests to share same Intel integrated videocard. Guest gets a near-native graphics peformance.

Win7-32 / Win7-64 / Win8.1-64 /Win10-RS1-64 are validated.

Hardware Requirements

For client platforms, 5th, 6th or 7th Generation IntelÂ® Core Processor Graphics is required. For server platforms, E3_v4, E3_v5 or E3_v6 Xeon Processor Graphics is required.

Select VGPU devices

Enable iGVT-g with

/etc/nixos/configuration.nix

  boot.kernelPackages = pkgs.linuxPackages_4_19;
  virtualisation.kvmgt.enable = true;

then rebuild and reboot. Choose virtual GPU

$ ls /sys/bus/pci/devices/0000:00:02.0/mdev_supported_types/
i915-GVTg_V5_4/  i915-GVTg_V5_8/

$ cat /sys/bus/pci/devices/0000:00:02.0/mdev_supported_types/i915-GVTg_V5_8/description 
low_gm_size: 64MB
high_gm_size: 384MB
fence: 4
resolution: 1024x768
weight: 2

Generate UUID

$ nix run nixpkgs.libossp_uuid -c uuid
a297db4a-f4c2-11e6-90f6-d3b88d6c9525

NixOS configuration

/etc/nixos/configuration.nix

  boot.kernelPackages = pkgs.linuxPackages_4_19;
  virtualisation.kvmgt.enable = true; 
  virtualisation.kvmgt.vgpus = {
    "i915-GVTg_V5_8" = {
      uuid = "a297db4a-f4c2-11e6-90f6-d3b88d6c9525";
    };
  };
  environment.systemPackages = with pkgs; [
  virtmanager
  virt-viewer
  ];
  virtualisation.libvirtd.enable = true;
  users.extraUsers.user.extraGroups = [ "libvirtd" ];

Configure KVM

Bare Qemu

  qemu-system-x86_64 \
     -enable-kvm \
     -m 1G \
     -nodefaults \
     -M graphics=off \
     -serial stdio \
     -display gtk,gl=on \
     -device vfio-pci,sysfsdev=/sys/bus/mdev/devices/a297db4a-f4c2-11e6-90f6-d3b88d6c9525,display=on,x-igd-opregion=on

libvirtd

If using virt-manager, create new or open existing VM.

sudo -E virsh edit win10

 <domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
 <devices>
 <graphics type='spice'>
  <listen type='none'/>
  <gl enable='yes'/>
 </graphics>
 <hostdev mode='subsystem' type='mdev' managed='no' model='vfio-pci'>
  <source>
    <address uuid='a297db4a-f4c2-11e6-90f6-d3b88d6c9525'/>
  </source>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>
 </hostdev>
 </devices>
  <qemu:commandline>
   <qemu:arg value='-set'/>
   <qemu:arg value='device.hostdev0.x-igd-opregion=on'/>
   <qemu:arg value='-set'/>
   <qemu:arg value='device.hostdev0.display=on'/>
  </qemu:commandline>
 </domain>

Finally use sudo virt-viewer --attach win10

FAQ

No video output

Possible solutions

(libvirtd) Change main adapter type from QXL to say Cirrus

(libvirtd) Connect via `virt-viewer --attach` to see igvt-g display, virt-manager console will not show it

use BIOS (SeaBIOS) machine, UEFI (OVMF) is not supported https://bugzilla.tianocore.org/show_bug.cgi?id=935 As a workaround you may create qcow boot image that is capable of booting UEFI disk with windows on BIOS machine http://winitpro.ru/index.php/2014/03/11/zagruzka-windows-7-s-gpt-na-bios-bez-uefi-2/#h2_5

ensure that the recent Intel graphics driver is installed in the guest

(libvirtd) "Element domain has extra content: qemu:commandline" error after editing via virsh

you forgot to add xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'

(libvirtd) "no drm render node available" error in virt-manager

in virt-manager change SPICE display render node from auto to available one

"write_loop: No space left on device" error when creating mdev device

check whether available instances are left

$ cat /sys/bus/pci/devices/0000\:00\:02.0/mdev_supported_types/i915-GVTg_V5_4/available_instances 
1

also check dmesg output for gvt related error, most likely there is not enough VRAM

There is no VGPU device that has resolution of my screen

Choose device that has higher resolution than yours than use this program in guest https://www.monitortests.com/forum/Thread-Custom-Resolution-Utility-CRU to set resolution you need

VM stops immediately with no error other than "internal error: process exited while connecting to monitor"

qemu might be exiting due to SIGSYS, which may be related to this bug: https://github.com/intel/gvt-linux/issues/47

Try disabling seccomp sandboxing in qemu like so:

virtualisation.libvirtd = {
  qemuVerbatimConfig = ''
    seccomp_sandbox = 0
  '';
};

Used sources

vgpu display support on a contributor (kraxel)'s blog - this guide misses info that Windows guest requires x-igd-opregion=on parameter and also that QXL may go into conflict
https://github.com/intel/gvt-linux/wiki/GVTg_Setup_Guide - obsoleted guide, but some parts are useful
https://github.com/intel/gvt-linux/wiki/Dma_Buf_User_Guide - obsoleted guide, but some parts are useful