id = 1891
title = "qemu 8.1.0 breaks gvt-g + qemu-ui-gtk w gl=on (black screen, qemu: eglCreateImageKHR failed)"
state = "closed"
created_at = "2023-09-15T10:25:40.593Z"
closed_at = "2023-10-10T01:28:04.205Z"
labels = ["GUI::GTK", "Stable::to backport", "VFIO", "host: x86", "workflow::Patch available"]
url = "https://gitlab.com/qemu-project/qemu/-/issues/1891"
host-os = "Manjaro latest, Artix latest"
host-arch = "x86_64"
qemu-version = "QEMU emulator version 8.1.0"
guest-os = "Windows 10 21H1"
guest-arch = "x86_64"
description = """As of 8.1.0, qemu-ui-gtk renders a black window with the error `qemu: eglCreateImageKHR failed` repeatedly appearing in the command line.


#"""
reproduce = """1. enable kernel modules, set parameters etc.
2. create vgpu
     `echo "$GVT_GUID" > "/sys/devices/pci0000:00/0000:00:02.0/mdev_supported_types/i915-GVTg_V4_2/create"`
3. launch VM
4. wait

Instructions (a small part of which I wrote by trial and error) for the setup are on the [Arch Wiki](https://wiki.archlinux.org/title/Intel_GVT-g).

#"""
additional = """Windows is installed directly to a second SSD, I dual-boot it.  
I've been using this exact VM, from libvirt, for almost two years.  
relevant sections:
```
    <hostdev mode="subsystem" type="mdev" managed="no" model="vfio-pci" display="off">
      <source>
        <address uuid="$GVT_GUID"/>
      </source>
    </hostdev>
  </devices>
  <qemu:commandline>
    <qemu:arg value="-display"/>
    <qemu:arg value="gtk,gl=on,zoom-to-fit=off"/>
    <qemu:env name="DISPLAY" value=":0.0"/>
  </qemu:commandline>
  <qemu:override>
    <qemu:device alias="hostdev0">
      <qemu:frontend>
        <qemu:property name="x-igd-opregion" type="bool" value="true"/>
        <qemu:property name="driver" type="string" value="vfio-pci-nohotplug"/>
        <qemu:property name="ramfb" type="bool" value="true"/>
        <qemu:property name="display" type="string" value="on"/>
        <qemu:property name="romfile" type="string" value="/home/user/VM/vbios_gvt_uefi.rom"/>
      </qemu:frontend>
    </qemu:device>
  </qemu:override>
```

The patched vBIOS necessary to use DMA-BUF with OVMF is linked there too, but its [successors](https://github.com/patmagauran/i915ovmfPkg) doesn't work either.

#"""