AMD+NVIDIA: why Xorg uses NVIDIA

Support Graphics & Display
1

Hi. I see Xorg process with my video-hybrid-amd-nvidia-prime driver.

[u@upc ~]$ nvidia-smi
Tue Sep 21 15:42:20 2021       
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 470.63.01    Driver Version: 470.63.01    CUDA Version: 11.4     |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|                               |                      |               MIG M. |
|===============================+======================+======================|
|   0  NVIDIA GeForce ...  Off  | 00000000:01:00.0 Off |                  N/A |
| N/A   41C    P3    12W /  N/A |      5MiB /  3910MiB |      0%      Default |
|                               |                      |                  N/A |
+-------------------------------+----------------------+----------------------+
                                                                               
+-----------------------------------------------------------------------------+
| Processes:                                                                  |
|  GPU   GI   CI        PID   Type   Process name                  GPU Memory |
|        ID   ID                                                   Usage      |
|=============================================================================|
|    0   N/A  N/A       972      G   /usr/lib/Xorg                       4MiB |
+-----------------------------------------------------------------------------+

How can I prevent that? Help please.

[u@upc ~]$ screenfetch
...
OS: Manjaro 21.1.3 Pahvo
Kernel: x86_64 Linux 5.13.15-1-MANJARO
DE: Xfce4
WM: Xfwm4
CPU: AMD Ryzen 5 5600H with Radeon Graphics @ 12x 3.3GHz
GPU: NVIDIA GeForce RTX 3050 Ti Laptop GPU

$ lspci | egrep 'VGA|3D'
01:00.0 VGA compatible controller: NVIDIA Corporation GA107M [GeForce RTX 3050 Ti Mobile] (rev a1)
05:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cezanne (rev c6)

xrandr --listproviders
Providers: number : 2
Provider 0: id: 0x55 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 4 outputs: 2 associated providers: 1 name:Unknown AMD Radeon GPU @ pci:0000:05:00.0
Provider 1: id: 0x1f8 cap: 0x2, Sink Output crtcs: 4 outputs: 2 associated providers: 1 name:NVIDIA-G0

$ glxinfo | grep "OpenGL renderer"
OpenGL renderer string: AMD RENOIR (DRM 3.41.0, 5.13.15-1-MANJARO, LLVM 12.0.1)
$ prime-run glxinfo | grep "OpenGL renderer"
OpenGL renderer string: NVIDIA GeForce RTX 3050 Ti Laptop GPU/PCIe/SSE2

I didn’t change default files in xorg.conf.d, here they are:

ls /usr/share/X11/xorg.conf.d/
10-amdgpu.conf                         10-evdev.conf                         10-quirks.conf  40-libinput.conf
10-amdgpu-nvidia-drm-outputclass.conf  10-intel-nvidia-drm-outputclass.conf  10-radeon.conf

[u@upc ~]$ cat /usr/share/X11/xorg.conf.d/10-amdgpu.conf
Section "OutputClass"
	Identifier "AMDgpu"
	MatchDriver "amdgpu"
	Driver "amdgpu"

[u@upc ~]$ cat /usr/share/X11/xorg.conf.d/10-amdgpu-nvidia-drm-outputclass.conf 
Section "ServerLayout"
    Identifier "layout"
    Option "AllowNVIDIAGPUScreens"
EndSection

Section "OutputClass"
    Identifier "AMDgpu"
    MatchDriver "amdgpu"
    Driver "amdgpu"
EndSection

Section "OutputClass"
    Identifier "nvidia"
    MatchDriver "nvidia-drm"
    Driver "nvidia"
    Option "AllowEmptyInitialConfiguration"
    ModulePath "/usr/lib/nvidia/xorg"
    ModulePath "/usr/lib/xorg/modules"
EndSection

[u@upc ~]$ cat /usr/share/X11/xorg.conf.d/10-intel-nvidia-drm-outputclass.conf 
Section "ServerLayout"
    Identifier "layout"
    Option "AllowNVIDIAGPUScreens"
EndSection

Section "OutputClass"
    Identifier "intel"
    MatchDriver "i915"
    Driver "modesetting"
EndSection

Section "OutputClass"
    Identifier "nvidia"
    MatchDriver "nvidia-drm"
    Driver "nvidia"
    Option "AllowEmptyInitialConfiguration"
    ModulePath "/usr/lib/nvidia/xorg"
    ModulePath "/usr/lib/xorg/modules"
EndSection
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