Dear Maintainer,

After a fresh install of Debian 11 on this machine (Kaveri A10-7850K), OpenGL
only worked for root, not for users.
Same for Radeon and amdgpu drivers.
Thinking this might be an issue of an old firmware and an old kernel, I
installed Debian 12.
But the problem still persists: OpenGL works for root (Firefox, FreeCAD,
glxheads), but not for other users.

When started as a normal user, OpenGL windows just seem to show garbled parts
of the memory. These bitmaps change when moving or resizing the Window, but
they don't show any changes related to the program.

I already checked the permissions:

 wolf-dieter@CSL6001:/dev/dri$ groups
 wolf-dieter adm dialout fax cdrom floppy tape sudo audio dip video plugdev
users render netdev bluetooth lpadmin scanner
 wolf-dieter@CSL6001:/dev/dri$ ls -l
 insgesamt 0
 drwxr-xr-x  2 root root         80 28. Dez 14:33 by-path
 crw-rw-rw-+ 1 root video  226,   0 28. Dez 14:33 card0
 crw-rw-rw-+ 1 root render 226, 128 28. Dez 14:33 renderD128
 wolf-dieter@CSL6001:/dev/dri$ glxheads :0
 Name: :0
   Display:     0x562aa03dbd10
   Window:      0x4000002
   Context:     0x562aa03fd1a0
   GL_VERSION:  4.6 (Compatibility Profile) Mesa 22.2.4
   GL_VENDOR:   AMD
   GL_RENDERER: AMD Radeon R7 Graphics (kaveri, LLVM 15.0.5, DRM 3.48,
6.0.0-6-amd64)

As OpenGL works for root, it looks like a permission problem. But which and
where?


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In order to get the PC usable, I have tried to disable the part of the
system causing the error.

Disabling GLX made no difference (Option "GLX" "Disable"),
but disabling the 2D hardware acceleration did it (Option "AccelMethod"
"none").

So with the latter setting, the PC is usable until there is a solution
to the hardware acceleration problem.

BTW:
A test with 2D acceleration and the ' Option "ShadowPrimary" "on" '
crashed the x-server, showing a backtrace on the console.
Possibly caused by the same issue.

In searching for the cause, I found that the failure of 2D acceleration
must be due to a user configuration problem rather than a permissions
problem.

The system partition and thus the roots folder were newly created, the
/home/ partition was taken over from the previous installation. This was
created years ago with Debian 9 (at that time with a radeon driver).

The 2D acceleration does not work for any of the old users. But it does
for  a completely new user or the new root-account created during the
installation.
So there must be a problem with the old user settings that prevents
access to the hardware acceleration memory or puts it on a wrong address.
No idea which one this should be and where to find it.
My solution now is to recreate the user directories and move the data
from the old directories there. Users will then have to redo their
settings, which is less tragic than not having 2D acceleration.