Why Blender Cycles is not able to detect my GPU(s) and CUDA within the Ubuntu / Linuxulator

From: Mario Marietto <marietto2008_at_gmail.com>
Date: Sat, 18 Feb 2023 14:59:49 UTC
Hello to everyone.

I've just installed Ubuntu 22.10 with the Linuxulator on FreeBSD
13.1-RELEASE p6 as well as these components inside it :

   1. nvidia driver Version: 525.78.01 + CUDA 12
   2. Blender 3.2.2

The nvidia driver 525.78.1 + CUDA 12 work correctly within the linuxulator :


and Cycles is already able to detect the nvidia driver + CUDA,but only if
blender runs on FreeBSD. Give a look at this picture :


What I want to do is to run Blender and I want to render my projects with
cycles using the CUDA libraries and my GPU(s) within the linux emulation
layer. Is this supposed to work ? The error that Blender gives when I try
to do that are the the following ones :

root@marietto:/# blender

Read prefs: /root/.config/blender/3.2/config/userpref.blend
libGL error: glx: failed to create dri2 screen
libGL error: failed to load driver: nouveau
could not get a list of mounted file-systems
/var/run/user/1001/gvfs/ non-existent directory
Saved session recovery to '/tmp/quit.blend'
Blender quit

why do I use root ? because as a normal user Blender does not start at all.

marietto@marietto:~$ blender
Unable to open a display

I'm very curious to understand the reason(s) of the errors I see below :

libGL error: glx: failed to create dri2 screen
libGL error: failed to load driver: nouveau

My sensation is that they can be fixed. If I do :

cp -r  ./blender-3.2.2-linux-x64/3.2/scripts/addons/cycles/lib

I see this additional error :

CUDA cuInit: Unknown error

but if I remove the lib directory :

rm -r /compat/ubuntu2210/usr/share/blender/scripts/addons/cycles/lib

the error "CUDA cuInit: Unknown error" disappears,but the other errors are
still there.

It seems to me that Blender looks for the nouveau driver and it can't find
it. But it should look like the nVidia driver. Since the nouveau driver
does not support CUDA,maybe it should be "unlinked" from Blender and
Blender should be "linked" to the nvidia driver,in some way. What do you
think ?