Re: [TECH TOPIC] vfio, iommufd: Enabling user space drivers to vend more granular access to client processes

[Jason Gunthorpe]

On Mon, Sep 22, 2025 at 10:46:23AM -0700, Alex Mastro wrote:

> Following a dma_buf_ops.mmap, I suppose that revocation would mean:

I'd investigate adding some ioctl to the dmabuf fd to permanently
revoke it. The zapping/etc already has to be done just to get mmap in
the first place. The vending process would retain a FD on the dmabuf
and when it is time to revoke it then it can call the ioctl directly
on the fd to revoke.

Jason