Making drm_gpuvm work across gpu devices

[David Airlie]

On Wed, Jan 31, 2024 at 8:29 AM Zeng, Oak <oak.zeng at intel.com> wrote:
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> Hi Christian,
>
>
>
> Nvidia Nouveau driver uses exactly the same concept of SVM with HMM, GPU address in the same process is exactly the same with CPU virtual address. It is already in upstream Linux kernel. We Intel just follow the same direction for our customers. Why we are not allowed?


Oak, this isn't how upstream works, you don't get to appeal to
customer or internal design. nouveau isn't "NVIDIA"'s and it certainly
isn't something NVIDIA would ever suggest for their customers. We also
likely wouldn't just accept NVIDIA's current solution upstream without
some serious discussions. The implementation in nouveau was more of a
sample HMM use case rather than a serious implementation. I suspect if
we do get down the road of making nouveau an actual compute driver for
SVM etc then it would have to severely change.

Dave.