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kocsv

Member

Registered: 2011-10-10

Posts: 22

Multiple X Servers on one nVidia card

Hello,

I have a problem and was trying to fix this for quite some time now:

Only the first X Server gets 3D acceleration through the binary nvidia driver.

$ DISPLAY=:0 glxinfo | grep OpenGL

OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce GTX 960/PCIe/SSE2
OpenGL core profile version string: 4.5.0 NVIDIA 378.13
OpenGL core profile shading language version string: 4.50 NVIDIA
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.5.0 NVIDIA 378.13
OpenGL shading language version string: 4.50 NVIDIA
OpenGL context flags: (none)
OpenGL profile mask: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.2 NVIDIA 378.13
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.20
OpenGL ES profile extensions:

$ DISPLAY=:1 glxinfo | grep OpenGL

OpenGL vendor string: VMware, Inc.
OpenGL renderer string: Gallium 0.4 on llvmpipe (LLVM 4.0, 256 bits)
OpenGL core profile version string: 3.3 (Core Profile) Mesa 17.0.5
OpenGL core profile shading language version string: 3.30
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 3.0 Mesa 17.0.5
OpenGL shading language version string: 1.30
OpenGL context flags: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.0 Mesa 17.0.5
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.00
OpenGL ES profile extensions:

I'm mostly sure this has worked at some point.

This is what the Xorg.1.log says:

$ grep -i -e '(WW)' -e '(EE)' /var/log/Xorg.1.log

        (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[  6680.017] (WW) `fonts.dir' not found (or not valid) in "/usr/share/fonts/100dpi/".
[  6680.017] (WW) `fonts.dir' not found (or not valid) in "/usr/share/fonts/75dpi/".
[  6680.017] (WW) Hotplugging is on, devices using drivers 'kbd', 'mouse' or 'vmmouse' will be disabled.
[  6680.017] (WW) Disabling Keyboard0
[  6680.017] (WW) Disabling Mouse0
[  6680.018] (EE) /dev/dri/card0: failed to set DRM interface version 1.4: Permission denied
[  6680.083] (EE) NVIDIA(0): Failed to initialize the GLX module; please check in your X
[  6680.083] (EE) NVIDIA(0):     log file that the GLX module has been loaded in your X
[  6680.083] (EE) NVIDIA(0):     server, and that the module is the NVIDIA GLX module.  If
[  6680.083] (EE) NVIDIA(0):     you continue to encounter problems, Please try
[  6680.083] (EE) NVIDIA(0):     reinstalling the NVIDIA driver.
[  6680.301] (WW) NVIDIA(0): Option "TwinView" is not used
[  6680.303] (EE) AIGLX: reverting to software rendering
[  6680.469] (EE) /dev/dri/card0: failed to set DRM interface version 1.4: Permission denied

The xorg.xonf was generated using the nvidia-xconfig program:

Can anyone give me a hint what is missing?

Greetings
Sven

kocsv

Member

Registered: 2011-10-10

Posts: 22

Re: Multiple X Servers on one nVidia card

OK, libglx.so is loaded from wrong path:

There is already a bug for this:
https://bugs.archlinux.org/task/53090

Adding the modulepath fixes this.

Last edited by kocsv (2017-05-10 12:15:17)

Lone_Wolf

Forum Moderator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 11,922

Re: Multiple X Servers on one nVidia card

The xorg.xonf was generated using the nvidia-xconfig program:

AL uses /usr/share/X11/xorg.conf.d/10-nvidia-drm-outputclass.conf to setup the modulepath and a few other things, using an xorg.conf file overrides those settings.

You'll have to merge the 10-nvidia-drm-outputclass.conf into the one created by nvidia-xconfig.
Even then you may have problems, nvidia-xconfig doesn't exactly have a good reputation wrt creating working setups.

It's best to treat the files it creates as a guideline about what to add to your own custom conf-file.

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

(A works at time B)  && (time C > time B ) ≠  (A works at time C)

kocsv

Member

Registered: 2011-10-10

Posts: 22

Re: Multiple X Servers on one nVidia card

Thanks for your response, Lone_Wolf.

Actually everything works now, simply added the modulepath in the (empty) Files section of the nvidia-xconfig config.
But you're right - I should have never trusted the output of this tool

Greetings
Sven