Luis Chamberlain sent out the modules changes today for the Linux 6.6 merge window. Most notable with the modules update is a change that better builds up the defenses against NVIDIA’s proprietary kernel driver from using GPL-only symbols. Or in other words, bits that only true open-source drivers should be utilizing and not proprietary kernel drivers like NVIDIA’s default Linux driver in respecting the original kernel code author’s intent.
Back in 2020 when the original defense was added, NVIDIA recommended avoiding the Linux 5.9 for the time being. They ended up having a supported driver several weeks later. It will be interesting to see this time how long Linux 6.6+ thwarts their kernel driver.
The userland differences are not too great, but I would assume a kernel module as significant as a modern GPU driver is pretty deeply tied to Linux’s kernel internals.
Nvidia maintains a driver for FreeBSD already, same version as Linux and everything. IIRC the closed-source portion is “unified” and they just build the interface for whatever OS.
The “Linux support” piece is on the application side.