alt Hacker NewsI have been bothering the VM team for years for VM GPU pass through. I worked on the Apple Silicon Mac Pro and it would have made way more sense if you could run a linux VM and pass through the GPU that goes inside the case!
Sadly, as you can tell, they have not taken me up on my requests. Awesome that other people got it working!
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What are the chances there will be another Mac Pro in the future?
Will Apple ever make a computer that makes Siracusa happy? (and do you have the "Believe" shirt?)
two semi interesting things to note around this:
1. Virtualization.framework seems to support some form of GPU passthrough from the host (granted, not eGPU - it's for the integrated GPU). I think the primary use case is having macOS guests get acceleration, while still sharing GPU time with the host. There is also a patch that recently hit QEMU mainline that supports using the "venus server" with virtio-gpu to support a similar functionality for Linux guests under Hypervisor.framework.
2. Apple internally has some kind of PCI Passthrough support available in Virtualization.framework. It seems like the code is shipped to customers in the framework, but it relies on some kind of kext or kernel component that isn't shipped in retail macOS. I can't say if that's intended to ever be released to customers, but clearly someone at Apple has thought about this the feature.
It feels like half the problem in this blog post is dealing with memory access issues induced by QEMU and the VM boundary... it's probably something dumb I'm missing, but if you boot up Ubuntu in Docker, wouldn't the NVIDIA drivers still load? And then you wouldn't have to fight Apple about the memory management because OSX would still own the memory?
I still believe the lack of NVIDIA GPU support in the Mac Pro will go down as one of the greatest missed opportunities in tech.
Anyway, the Mac Pro is dead now. There's only so much sales audio and video professionals can provide.
It looks like the pass through part here was implemented using standard DriverKit interfaces, if I'm not mistaken. That is, the PCIe BAR can already be mapped from the user-space, without any extra modifications to macOS. It's just a matter of VMMs, such as QEMU, adopting this interface in addition to Linux VFIO and the like (unless you're talking about Virtualization.framework, which is kind of a VMM of its own).
What exactly do you feel macOS is missing?