It is meaningful because, as you note, it enables a fully opensource userspace driver. Of course the firmware is still proprietary and it increasingly contains more and more logic.
Personally, I somewhat wonder about that. The firmware (proprietary) which runs on the gpu seems like it'll have access to do things over the gpu PCIe bus, including read system memory, and access other devices (including network gear). Reading memory of remote hosts (ie RDMA) is also a thing which Nvidia gpus can do.
An IOMMU does solve it, at the cost of some performance. The GPU can only access memory that the IOMMU allows, and the part that programs the IOMMU is open source.
RDMA requires a special network card and is opt-in - an RDMA NIC cannot access any random memory, only specially registered regions. One could argue that a NIC FW bug could cause arbitrary memory accesses, but that's another place where an IOMMU would help.
The GLX libraries are the elephant(s) in the room. Open source kernel modules mean nothing without these libraries. On the other hand AMD and Intel uses "pltform GLX" natively, and with great success.
Mesa already provides good open source GLX and Vulkan libraries. An open source NVIDIA kernel driver enables interoperability with Mesa exactly like Intel and AMD.
Half of the trade secrets NVIDIA has are living in their own GLX libraries. Even if you install the open source kernel module, these GLX libraries are installed (just did it on a new cluster).
I’m not holding my breath about these libraries to be phased out and NVIDIA integrates to the platform GLX any time soon.
I think NVIDIA will resist moving to a firmware only model (ala AMD & Intel) as long as they can, preferably forever.
the open kernel driver also fundamentally breaks the limitation about geforce gpus not being licensed for use in the datacenter. that provision is a driver provision and CUDA does not follow the same license as the driver... really the only significant limitation is that you aren't allowed to use the CUDA toolkit to develop for non-NVIDIA hardware, and some license notice requirements if you redistribute the sample projects or other sample sourcecode. and yeah they paid to develop it, it's proprietary source code, that's reasonable overall.
so yeah, I'm not sure where the assertion of "no progress" and "nothing meaningful" and "this changes nothing" come from, other than pure fanboyism/anti-fans. before you couldn't write a libre CUDA userland even if you wanted to - the kernel side wasn't there. And now you can, and this allows retiming and clock-up of supported gpus even with nouveau-style libre userlands. Which of course don't grow on trees, but it's still progress.
honestly it's kinda embarrassing that grown-ass adults are still getting their positions from what is functionally just some sick burn in a 2004 viral video or whatever, to the extent they actively oppose the company moving in the direction of libre software at all. but I think with the "linus torvalds" citers, you just can't reason those people out of a position that they didn't reason themselves into. Not only is it an emotionally-driven (and fanboy-driven) mindset, but it's literally not even their own position to begin with, it's just something they're absorbing from youtube via osmosis.
Apple debates and NVIDIA debates always come down to the anti-fans bringing down the discourse. It's honestly sad. https://paulgraham.com/fh.html
it also generally speaks to the long-term success and intellectual victory of the GPL/FSF that people see proprietary software as somehow inherently bad and illegitimate... even when source is available, in some cases. Like CUDA's toolchain and libraries/ecosystem is pretty much the ideal example of a company paying to develop a solution that would not otherwise have been developed, in a market that was (at the time) not really interested until NVIDIA went ahead and proved the value. You don't get to ret-con every single successful software project as being retroactively open-source just because you really really want to run it on a competitor's hardware. But people now have this mindset that if it's not libre then it's somehow illegitimate.
Again, most CUDA stuff is distributed as source, if you want to modify and extend it you can do so, subject to the terms of the CUDA license... and that's not good enough either.
