Modules or sysctl settings not loading

Things fail at random after boot: a driver is missing, /etc/sysctl.d values are not applied, or a service behaves differently from one boot to the next.

Cause

ps5-stage-firmware.service can create a systemd ordering cycle. To break the cycle, systemd skips one of the units in it, and the ones skipped can be systemd-sysctl and systemd-modules-load. Nothing visible fails, so the symptom is only that settings are missing.

Not tested

Reported with the official CachyOS image. Other images may not have this service. Check with the command below before you change anything.

Check for the cycle

journalctl -b | grep -i "ordering cycle"

No output means you don't have this problem.

Fix

Add one line under [Unit] in the service file:

sudo systemctl edit --full ps5-stage-firmware.service

[Unit]
DefaultDependencies=no

Reboot, then run the check again. It should print nothing.