Re: linux-c7 and opengl apps?

On 10/3/18 5:36 AM, Johannes Lundberg wrote:
> Hi
>
> Have anyone successfully run opengl apps with linux-c7?
>
> Linux opengl apps works great with linux-c6 on gpu < kabylake but
> linux-c6-dri does not include support for kabylake gpus.
> Linux glxinfo in c7 show support for hardware rendering on kabylake but any
> attempt to run an opengl app results in application seg fault or other
> crash (I believe this is also the case with skylake gpus on linux-c7).
>
> Is there any way to run gdb on linux apps/core dumps?
>
> /Johannes
> _______________________________________________
On an Intel Skylake graphics system it has never worked:
% /compat/linux/opt/VirtualGL/bin/glxinfo | grep OpenGL
libGL error: MESA-LOADER: failed to retrieve device information
libGL error: Version 4 or later of flush extension not found
libGL error: failed to load driver: i915
libGL error: MESA-LOADER: failed to retrieve device information
OpenGL vendor string: Intel Open Source Technology Center
OpenGL renderer string: Mesa DRI Unknown Intel Chipset
OpenGL version string: 1.3 Mesa 17.0.1

Running any Linux OpenGL app which attempts to do actual rendering 
results in an indefinite freeze of the console: graphical output is 
frozen, and system does not respond to keyboard (Ctrl-Alt-Del or 
Ctrl-Alt-F1).  However, the system continues to run (tested with ssh).  
Sometimes, after several minutes, the console recovers, the OpenGL user 
segfaults, and the system returns to normal (until the next attempt to 
use an OpenGL Linux app).

This problem has existed forever.  I am not sure it is actually a fault 
in Linux emulation, as these very same symptoms ("failed to retrieve 
device information" message, console freeze) existed back in 
FreeBSDDesktop/freebsd-base-graphics days when attempting to run purely 
FreeBSD OpenGL apps.  At the time the workaround was a patch to Mesa's 
GPU detection; the underlying kernel problem wasn't addressed.

Where would I begin to investigate the problem, in order to fix it 
and/or to decide who's bug it is?  Unless there is something simpler to 
try, I may have to dig up those old Mesa patches and see whether a 
non-Linux binary can be made to trigger the same symptom.

By design, is it considered acceptable that any member of the "video" 
group has permission to destroy functionality of the graphics 
subsystem?  Is this a bug in the general case, or an accepted technical 
limitation?

Copying to x11_at_.

Theron