On one system with the 470.199.02 driver on kernel 6.5.9, I get udev events when I unplug a monitor, but on another system with 545.29.06 and kernel 6.5.8 I don’t get any. I’m monitoring with udevadm monitor --property.
This would be on OpenSUSE Tumbleweed and Slowroll respectively.
Is this a known issue with 545.29.06?
I’m running kernel 6.7 and driver 545.29.06 (on Arch) and recently saw what I assume is a similar issue (i.e. udev events not being sent for monitor hotplugs). In my case, the issue seems to be the result of my setting the nvidia_drm.fbdev=1 kernel parameter, either in the kernel command line or via a file in /etc/modprobe.d/.
The fbdev parameter is apparently still experimental, and has a variety of other known issues (per the ArchWiki). It may be worth checking whether your Slowroll system sets it. This is most easily done by cat’ing /sys/module/nvidia_drm/parameters/fbdev (as root).
Thanks for the suggestion, fbdev does appear to be on. (Actually, I stated the wrong order, it was Tumbleweed that I have on 545.29.06, Slowroll works OK on the much older driver.)
I’m not setting nvidia_drm.fbdev=1, but /sys/module/nvidia_drm/parameters/fbdev is reporting Y. Somehow fbdev is being turned on. I managed to figure out a boot line that would disable it:
BOOT_IMAGE=/boot/vmlinuz-6.5.8-1-default root=UUID=453caaf5-5fed-43d8-b823-58f4ded3ab63 resume=/dev/disk/by-label/swap splash=silent quiet showopts libata.force=2.00:noncq acpi_enforce_resources=lax modeset=0 nvidia-drm.modeset=0 nvidia-drm.fbdev=0 mitigations=auto
After booting with these arguments, cat /sys/module/nvidia_drm/parameters/fbdev is reporting N. But udevadm monitor --property still isn’t reporting any hotplug events.
The mystery remains.
Booting with fbdev disabled causes some DDC issues. I found libddcutil 2.1 fails to getvcp values for a DisplayPort connected monitor, but the problem goes away if I revert my boot parameters to: modeset=1 nvidia-drm.modeset=1 without any setting for fbdev.
But DDC with newer drivers is already dodgy, as I’ve already reported: NVIDIA 535.43.03 breaks DDC/CI for some monitors