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I will move most of them into the 0/X patch in v2. >> >>> Anyway, you didn't cc: the io_uring list, why? >>> >> `scripts/get_maintainer.pl` didn't output the io_uring mailing list, likely >> because this patch doesn't directly touch the io_uring codebase itself. It only >> enables remapping GPU memory buffers to CPU virtual addresses, which can then be >> consumed via standard io_uring APIs. >> >> I've added io-uring@vger.kernel.org to CC for this reply and will keep it in v2. > > Great, as you are using that as the api, there might be some parts that > will need to be reviewed by them. > >>> Nor why "fgds" is the name, that's going to be hard to remember, does it >>> stand for something? >>> >> "FGDS" stands for Fast GPUDirect Storage. GPUDirect Storage (GDS) is NVIDIA's >> technology enabling direct I/O between GPU memory and files on NVMe, >> widely used in LLM workloads to bypass CPU overhead. > > That's nvidia's specific solution, but this works on other devices, > right? Or just for that one platform? That was nvidia's specific and very hacky out of tree solution which as far as I know is pretty much abandoned everywhere. AMD came up with something similar, but all those approaches are so fundamentally broken that we didn't even considered upstreaming it. > And you are using this as a "bypass" for the normal accel subsystem, > shouldn't this be part of that subsystem instead of a custom user/kernel > api like you are creating here? As far as I know there is a patch set under review and even already partially merged which enables exactly that functionality as general feature for DMA-buf which is vendor independent and should at least in theory work with all drivers. I'm really surprised that somebody is still working on the vendor specific stuff. Regards, Christian. > > thanks, > > greg k-h