3D acceleration for Kicksecure VMs

Development
1

Creating this so I have something to reference for documentation on the wiki.

While attempting to update the glmark2 instructions for Kicksecure 18, I discovered that 3d acceleration under VirtualBox is a mess, at least when using VMSVGA graphics. So far:

  • With 3d accel disabled, everything seems OK, glmark2-wayland runs without problems, but naturally it uses the CPU for everything.
  • With 3d accel enabled, glmark2-wayland still uses CPU rendering by default, because labwc is started with WLR_RENDERER=pixman set by default. One has to unset this environment variable before starting labwc to get 3d acceleration capabilities to be recognized. Technically this is a Kicksecure limitation that could be fixed.
  • If you are running with low memory (in my case 768 MB, I had left the VM with this amount of memory on accident), 3d accel is enabled, and glmark2-wayland is NOT using 3d accel (i.e. WLR_RENDERER=pixman is set), the VM will spontaneously hang or reboot during the glmark2-wayland test. This is because something (didn’t have the presence of mind to record what) in the kernel ends up doing the equivalent of a segfault, which results in a kernel oops, which results in a kernel panic, which results in an instant reboot..
  • If you attempt to run glmark2 (just plain glmark2, which will go through Xwayland) without using CPU rendering (WLR_RENDERER=pixman), the glmark2 window will briefly flash on-screen and then vanish.
  • If you attempt to run glmark2 (the X11 version) with GPU rendering (WLR_RENDERER unset when labwc is started), it will immediately crash labwc itself when launched.
  • If you attempt to run glmark2-wayland with GPU rendering (WLR_RENDERER unset when labwc is started), it will immediately error out:
=======================================================
    glmark2 2023.01
=======================================================
    OpenGL Information
    GL_VENDOR:      VMware, Inc.
    GL_RENDERER:    SVGA3D; build: RELEASE;  LLVM;
    GL_VERSION:     4.1 (Compatibility Profile) Mesa 25.0.7-2
    Surface Config: buf=32 r=8 g=8 b=8 a=8 depth=24 stencil=0 samples=0
    Surface Size:   800x600 windowed
=======================================================
[build] use-vbo=false:[destroyed object]: error 7: importing the supplied dmabufs failed
 FPS: 1037 FrameTime: 0.965 ms
=======================================================
                                  glmark2 Score: 1036 
=======================================================

At this point I’m pretty sure 3d rendering in VirtualBox is just broken. It might work better if using VBoxSVGA graphics, but as I understand it, the 3d acceleration code for that graphics emulator is insecure and can be used for a VM escape.

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