GPU / render support only kind of working (permissions?)

[happy-dirac]

Hi,

I ran into some kind of issue regarding GPU support.

image: kasmweb/ubuntu-focal-desktop:1.11.0 and anything built on kasmweb/core-ubuntu-focal:1.11.0 Host-OS: ubuntu-server 22.04 LTS

Expected behavior:

• Images for kasm, regardless of being executed standalone or through kasm, should have access to /dev/dri/card0 and and /dev/dri/renderD128, after reboot "old" kasm-sessions should work as before

Observed behavior:

• after reboot, standalone execution does not have access. glxinfo -B shows software/MESA rendering, no process in nvidia-smi
• launching the same image through kasm will make it work, glxinfo -B shows my NVIDIA card, nvidia-smi shows xfce4-session
• any subsequently launched standalone image works, glxinfo -B shows NVDIA card and nvidia-smi shows additional xfce4-session
• after reboot, reentering the old kasm session: glxinfo -B shows software/MESA rendering, no processes in nvidia-smi
• launching an additional kasm-session does not work due to lack of resources, which would be expected provided the old session still occupies them
• launching standalone reverts back software/MESA
• deleting the old session and starting a new one will again "fix" it, until reboot.

Other observations:

• kasm-session after reboot "looses" access to NVENC, standalone sessions will always have NVENC in OBS, regardless of access to gpu-rendering
• vglrun -d /dev/dri/card0 glxinfo -B will show normal NVIDIA info in all working instaces/sessions, on non-working sessions it outputs "libEGL warning: failed to open /dev/dri/renderD128: Permission denied"

I assume this is some kind of permissions issue, however I could not find a fix/solution. I believe the kasm-agent somehow fixes it when initially launching a gpu-accelerated session, but handles it differently after reboot while still believing that the ressources are allocated. Main concern is that in case of a reboot of the host/server-OS, the user on the GPU-accelerated session is forced to delete the session and create a new one to regain hardware acceleration. However, for testing/development purposes it would also come in handy if it is possible to launch an image without having to "preinitialize" the host by launching a gpu-accelerated image through kasm.

I am not that much of a linux/permissions guru, therefore any idea for a fix or workaround is highly appreciated.

Best,

H.

[happy-dirac]

wrong place, i guess, please see: https://github.com/kasmtech/workspaces-issues/issues/272