I see many articles about this issue but always on wayland. I just updated my system using yay, and around 218 packages got updated including linux, linux-headers, nvidia-dkms, plasma, etc. It went fine, but once I rebooted my computer and logged in using sddm into my X11 session, all I got was a black screen with no plasma panel. I could still move the cursor, open konsole with ctrl+alt+t and open applications like the browser, which all work perfectly. But my desktop is blank, I cannot open the application launcher using the meta button, and I get the error message ‘plasmashell closed unexpectedly’ three times every time I log in. Wayland does not work either (never really has), but nvidia-smi works like a charm so the gpu is still recognized. I tried downgrading the linux, linux-headers, nvidia-dkms, nvidia-utils and kwin to previous versions with the same end result. I tried adding nvidia_drm.fbdev=1 to my /etc/kernel/cmdline but there is no visible difference.
Here is my /etc/kernel/cmdline:
nvme_load=YES nowatchdog rw root=UUID=7b464e4a-1f0e-4195-bbb6-26ad501e7c8b resume=UUID=6280ed16-fd2b-441e-9781-5632d9737cf8 nvidia-drm.modeset=1
Please let me know if I need to upload anything else. Thank you.
Another issue that might be related, when the lid of the laptop is closed, the laptop suspends briefly (as expected). But in a couple of seconds, it powers on again, as I can see on my external monitor. This behaviour was not exhibited before said kernel update.