ddterm/gnome-shell-pod

X11 session on Fedora 37 only shows a black screen

Schneegans opened this issue · 4 comments

Schneegans commented

I recently tried to create a Fedora-37-based container for https://github.com/Schneegans/gnome-shell-pod and failed to properly start GNOME Shell under X11. I then looked into your fork to see if you managed to find a solution for this issue - and AFAIK your Fedora 37 image suffers from the same issue. Here's what I did:

podman run --rm --cap-add=SYS_NICE,SYS_PTRACE,SETPCAP,NET_RAW,NET_BIND_SERVICE,DAC_READ_SEARCH -ti ghcr.io/ddterm/gnome-shell-pod/fedora-37:2022.11.03.0

And then inside the container:

systemctl --user start "gnome-xsession@:99"

If I then inspect the virtual xvfb screen (podman cp $(podman ps -q -n 1):/run/Xvfb_screen0 . && convert xwd:Xvfb_screen0 capture.jpg && eog capture.jpg), I only get this:

capture

If I start the wayland session instead (systemctl --user start "gnome-wayland-nested@:99"), I can see GNOME Shell properly:

capture

With your Fedora-36-based image, both sessions do work.

Can you reproduce this? Do you have an idea what could be causing this? I inspected the output of GNOME Shell and did not find anything suspicious.

Thank you!

amezin commented

And exactly the same issue on Ubuntu 22.10.

Also, while the screen is blank, all my tests are passing - from window manager's point of view, there are windows on the screen, and everything is working...

amezin commented

Actually, it's not always black screen. For some tests, I get correct screenshots. For some - black screen. It's likely a bug in GNOME Shell + Xvfb.

Schneegans commented

I tested it again and it works now! So whatever caused the issue, it seems to have been fixed.

amezin commented

Recently I:

  • Enabled TCP access to Xorg - I doubt it changed anything for rendering

  • Modified the set of installed packages multiple times - which caused updates and rebuilds

So I guess it's fixed by package updates in Fedora