Re: [PATCH v4 1/5] PCI/P2PDMA: Don't enforce ACS check for device functions of Intel GPUs

[Jason Gunthorpe <jgg@nvidia.com>]

On Mon, Sep 22, 2025 at 03:20:49PM +0200, Christian König wrote:

> At least on AMD GPUs when you want to have a DMA-buf for a specific
> part of the VFs resources then you ask the hypervisor driver
> managing the PF for that and not the VFIO driver.

Having a UAPI on the PF to give DMABUFs for arbitary VRAM seems
security exciting. I'd probably want to insist the calling process
prove to the PF driver that it also has access to the VF.

Having the VF create the DMABUF is one way to do that, but I imagine
there are other options.

But sure, if you can solve, or ignore, the security proof it makes a
lot more sense.

Jason