Bug#900248: nvidia-driver: update to 390.59 breaks direct rendering

[floris]

> 
> What about the following 
> /etc/nvidia/current/nvidia-drm-outputclass.conf
> 
> ---------------------------------------------------
> Section "Files"
>     ModulePath     "/usr/lib/xorg/modules/linux"
>     ModulePath     "/usr/lib/xorg/modules"
> EndSection
> 
> Section "OutputClass"
>     Identifier     "nvidia"
>     MatchDriver    "nvidia-drm"
>     Driver         "nvidia"
> EndSection
> ---------------------------------------------------
> 
> That seems to work for stable ... what about sid?
> 
> 
> Andreas

Hmmm, this should work, but the NVidia glx module will always be loaded 
for all screens by the xserver. This will break a multiseat system with 
multiple gpu vendors and maybe other glvnd dispatch goodness.

Is the following situation a possibility?

Stable -> nvidia-driver (up to version 390.xx in backports), compatible 
with all versions of the xserver
  This version is shipped with a separate Files section in 
nvidia-drm-outputclass.conf
  If xserver 1.20 is in backports, this version can be upgraded to match 
the new Testing/Sid version

Testing and Sid -> nvidia-legacy-390xx-driver, xserver > 1.20
                 -> nvidia-driver (version > 396.xx), xserver > 1.20
  These versions will have the ModulePath option in the OutputClass 
section. (and we can drop the glx-alternative system)
---
Floris