I have a P1 Gen 2 with Ubuntu installed. My USB-C ports on the left side of my computer don't work for some reason (might be a cable issue). There really isn't any support from Lenovo for Linux. I'm fine with it for now, but I think the certification is for a specific build of the OS + (one? idk) run from Canonical, as opposed to a comprehensive test from an OEM (e.g. like those monitor color/brightness reports you get during unboxing).