Must restart system to switch to nvidia

Describe the bug Can switch to nvidia driver if I set it as startup. Can switch back to intel and relogin to apply. Cannot switch to nvidia unless a full restart is applied. No error trying to switch to nvidia in session, but it just doesn’t switch. Modprobe error in the gpu_setup.log below.

System info

• Arch 5.4.15-arch1-1
• KDE
• Dell G3, nvidia 1050M GTX
• latest Git version (optimus-manager-git)

Logs boot_setup.log gpu_setup.log prime_setup.log

pacman -Q | grep nvidia
nvidia 440.44-15
nvidia-utils 440.44-3

[root@xonq /]# lsmod | grep "kms\|drm"
nvidia_drm             49152  5
nvidia_modeset       1118208  7 nvidia_drm
drm_kms_helper        212992  2 nvidia_drm,i915
drm                   520192  9 drm_kms_helper,nvidia_drm,i915
agpgart                53248  2 intel_gtt,drm
syscopyarea            16384  1 drm_kms_helper
sysfillrect            16384  1 drm_kms_helper
sysimgblt              16384  1 drm_kms_helper
fb_sys_fops            16384  1 drm_kms_helper

[root@xonq modprobe.d]# grep LoadModule /var/log/Xorg.0.log
[     8.725] (II) LoadModule: "glx"
[     8.741] (II) LoadModule: "nvidia"
[     8.751] (II) LoadModule: "modesetting"
[     8.758] (II) LoadModule: "fb"
[     8.760] (II) LoadModule: "wfb"
[     8.761] (II) LoadModule: "ramdac"
[     8.774] (II) LoadModule: "glxserver_nvidia"
[     8.914] (II) LoadModule: "glamoregl"
[     9.165] (II) LoadModule: "fb"
[     9.244] (II) LoadModule: "dri2"
[     9.746] (II) LoadModule: "libinput"

[ahegazy]

Figured out the problem as per the FAQ you have to

I do not use a display manager (I use startx or xinit) Just like above, you must make sure to run /usr/bin/prime-offload (as normal user) just after the X > server is started, and /usr/bin/prime-switch (as root) after it has stopped.

so prime-switch needed to run as root after every Xserver exit, without display manager you have to make it run manually to make the switch,

Auto

• In the ~/.xinitrc you run your window manager for example exec i3 replace it with only i3
• Edit the /etc/sudoers adding this line YourUserName ALL = NOPASSWD: /usr/bin/prime-switch to prevent it from requiring a password when writing sudo /usr/bin/prine-switch
• after the window manager running command write your sudo /usr/bin/prime-switch Then end of the .xinitrc will be

i3
sudo /usr/bin/prime-switch

-that’s it

Problem with this

• when switching from nvidia to intel, we run prime-switch before the xserver is fully killed so this error is produced Setting up base state Unloading modules ['nvidia_drm', 'nvidia_modeset', 'nvidia'] (if loaded) Cannot setup GPU : kernel setup error : Cannot unload modules ['nvidia_drm', 'nvidia_modeset', 'nvidia'] : Failed to execute 'modprobe -r nvidia_drm nvidia_modeset nvidia' : modprobe: FATAL: Module nvidia_drm is in use.

soultion

• Instead of making it run at the end of xserver, run it before running xserver
• So i have my .bash_profile having the startx command
• before it add sudo /usr/bin/prine-switch
• so my .bash_profile is

#
# ~/.bash_profile
#
[[ -f ~/.bashrc ]] && . ~/.bashrc

if systemctl -q is-active graphical.target && [[ ! $DISPLAY && $XDG_VTNR -eq 1 ]];
then 
    sudo /usr/bin/prime-switch
    exec startx
fi

Manually

• add this option to optimus-manager.conf auto_logout=no
• this prevents auto logout when switching, so after the switch command, run /usr/bin/prime-switch as root

[khuedoan]

Thanks @ahegazy, your solution works great!

Also if anyone using sudo with password like me, you can add this line to /etc/sudoers with visudo to allow the sudo /usr/bin/prime-switch command to run without a password:

%wheel ALL=(ALL) NOPASSWD: /usr/bin/prime-switch