[Linaro-mm-sig] Re: [PATCH v6 9/9] vfio/pci: Permanently revoke a DMABUF on request

On Mon, Sep 14, 2026 at 01:13:36PM +0100, Matt Evans wrote:

"This is useful for lifecycle management, to reclaim VFIO PCI BAR ranges previously delegated to a subordinate client process: by revoking, the driver process can ensure that the loaned resources are made inaccessible when the client is deemed "done". The original DMABUF is defunct, and BAR resources can then be safely re-exported for use by new clients."

This makes the point clear, you want a way to permanently revoke a specific dmabuf fd and render it forever unable to access any underlying memory.

You want to do this so the vendor can fence the vendee without requiring its co-operation.

"temporary revoke" ie what VFIO already does around reset is a different thing.

Jason