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Created attachment 1930369[details]
journal log
Description of problem:
When using Xephyr to access local session via xdmcp, nothing happens, only black screen.
Version-Release number of selected component (if applicable):
gdm-40.0-25.el8.x86_64
gnome-shell-3.32.2-50.el8.x86_64
xorg-x11-server-Xephyr-1.20.11-10.el8.x86_64
How reproducible:
100%
Steps to Reproduce:
1. Xephyr :99 -query localhost -fullscreen
2.
3.
Actual results:
Black screen.
Expected results:
Login screen loads.
Additional info:
$ cat /etc/gdm/custom.conf
[daemon]
WaylandEnable=false
AutomaticLoginEnable = true
AutomaticLogin = test
[security]
[xdmcp]
Enable=true
[chooser]
[debug]
Enable=true
What jumps out to me is the line: "Cannot use session '/usr/share/gdm/greeter/gnome-session/sessions/gnome-login.session': non-existing or invalid file" which might be relevant since the login screen does not load.
Comment 3Ray Strode [halfline]
2022-12-06 15:15:26 UTC
this seems to be a mesa regression of some sort following a rebase.
The login screen is there, it's just not painting. The mouse cursor even changes when hovering over where the password field should be.
It happens when going from mesa-22.1.5-2.el8 to mesa-22.3.0-0.4.rc4.el8
Comment 4Ray Strode [halfline]
2022-12-06 15:29:53 UTC
hmm it's not a problem with software rendering apparently. Xephyr works fine with glxgears and with mutter even, so it seems like it's a problem specific to remote x servers. maybe some sort of shm issue?
(In reply to Ray Strode [halfline] from comment #4)
> hmm it's not a problem with software rendering apparently. Xephyr works fine
> with glxgears and with mutter even, so it seems like it's a problem specific
> to remote x servers. maybe some sort of shm issue?
See if the patch I posted in bug 2092450 helps here.
Comment 6Ray Strode [halfline]
2022-12-06 16:37:36 UTC
it seems to a problem with shm detection.
Xephyr -extension mit-shm -query localhost :123
makes it work. So I guess it's trying to use XShmPutImage over a tcp display connection.
Comment 7Ray Strode [halfline]
2022-12-06 17:36:54 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory (mesa bug fix and enhancement update), and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://access.redhat.com/errata/RHBA-2023:2824
Created attachment 1930369 [details] journal log Description of problem: When using Xephyr to access local session via xdmcp, nothing happens, only black screen. Version-Release number of selected component (if applicable): gdm-40.0-25.el8.x86_64 gnome-shell-3.32.2-50.el8.x86_64 xorg-x11-server-Xephyr-1.20.11-10.el8.x86_64 How reproducible: 100% Steps to Reproduce: 1. Xephyr :99 -query localhost -fullscreen 2. 3. Actual results: Black screen. Expected results: Login screen loads. Additional info: $ cat /etc/gdm/custom.conf [daemon] WaylandEnable=false AutomaticLoginEnable = true AutomaticLogin = test [security] [xdmcp] Enable=true [chooser] [debug] Enable=true What jumps out to me is the line: "Cannot use session '/usr/share/gdm/greeter/gnome-session/sessions/gnome-login.session': non-existing or invalid file" which might be relevant since the login screen does not load.