> This also enables third party APIs, such as the popular NVIDIA Cuda compute API, to be hardware accelerated within a WSL environment.
Dollars to donuts this is why Microsoft is implementing this. GPU acceleration is becoming a critical feature for many users (but especially developers) and this will continue. If WSL is to be a serious competitor, this is necessary and I'm glad to see it showing up. This is true of cloud compute, too, and Microsoft is betting big on cloud as its future growth area.
> Only the rendering/compute aspect of the GPU are projected to the virtual machine, no display functionality is exposed.
The Linux gaming folks will be pretty sad about this one. Anyway, this isn't really a Linux port of DirectX. This is GPU compute via DirectX APIs.
So now, I'm just waiting on monitor mode/AF_PACKET for WSL...
Yup, from one of the MS staff replies further in the thread[1]
> There is a single usecase for this: WSL2 developer who wants to run machine learning on his GPU. The developer is working on his laptop, which is running Windows and that laptop has a single GPU that Windows is using.
Can't say I can get behind MS trying to shift maintenance for a Windows only "feature" onto the Linux devs here.
Is there a possibility Linux upstream won't accept it?
If you read the replies by Dave Airlie and Daniel Vetter, it seems somewhat likely that upstream won't accept it. Perhaps that's just initial skepticism that will evaporate after more discussion, but perhaps not.
Frankly this does just seem like MS wanting to reduce their maintenance burden on what they expect will be a very important part of their WSL offering on Windows. There's nothing inherently wrong with that desire, but the people on the other side need to weigh their maintenance burden[0] with what benefit this will have to the Linux community as a whole, which at first blush seems minimal. Especially considering that the userland pieces that talk to this driver aren't open-source.
There's also the question of whether or not you believe WSL as a whole is good or bad for Linux. If there are people who would run a Linux desktop for development who then decide not to because WSL exists, perhaps that's a bad outcome. If you have people writing more DirectX GPGPU code who would otherwise write to a standard interface like OpenCL, perhaps that's a bad outcome (to be fair, there's also a lot of CUDA out there, which is similarly problematic). Is this the start of MS going back to their "Embrace, Extend, Extinguish" playbook, or is that just a paranoid fear? They've definitely been embracing Linux, and enabling people to write DX12 GPGPU code that targets a Linux environment but will only run under WSL on a Windows install does feel like "extend".
I'm not sure where I personally stand on this issue as I haven't done my research, but I think they're interesting questions to ask.
If this gets rejected, of course it doesn't stop MS from doing any of these things, but it does make it harder for them to maintain their extensions to Linux.
[0] Airlie is even concerned that just by looking at the code, he or other DRI developers could run into future IP derived-works trouble when designing future Linux graphics interfaces.
>>>There's also the question of whether or not you believe WSL as a whole is good or bad for Linux.
IMO it's a good thing. Given that windows accounts for 90%+ of the desktop OS share, Windows might very well become the world's most used Linux distro.
It is, of course, decidedly not a Linux distro though. If it was, it wouldn't be an issue. I think there are positives, but it looks a lot like "Extend" to me.
I can't even say I wouldn't use it - it might be nice! But I will not use any WSL-only capability, that's for sure.
WSL2 literally runs user-mode distros (and their binaries) in containers atop a shared Linux kernel image (https://github.com/microsoft/WSL2-Linux-Kernel) inside a lightweight VM that can boot an image from cold in < 2s and which aggressively releases resources back to the host when freed.
So when you run a binary/distro on WSL2, you are LITERALLY running on Linux in a VM alongside all your favorite Windows apps and tools.
If some of the tools you run within WSL can take advantage of the machine's available GPUs etc. and integrate well with the Windows desktop & tools, then you benefit. As do the many Windows users who want/need to run Linux apps & tools but cannot dual-boot and/or who can't switch to Linux full-time.
This will (and already has) resulted in MANY Windows users getting access to Linux for the first time, or first time in a while, and are now enjoying the best of both worlds.