On Thu, Oct 16, 2025 at 11:32:59PM -0700, Christoph Hellwig wrote: > On Mon, Oct 13, 2025 at 06:26:10PM +0300, Leon Romanovsky wrote: > > From: Leon Romanovsky <[email protected]> > > > > Make sure that all VFIO PCI devices have peer-to-peer capabilities > > enables, so we would be able to export their MMIO memory through DMABUF, > > How do you know that they are safe to use with P2P?
All PCI devices are "safe" for P2P by spec. I've never heard of a non-complaint device causing problems in this area. The issue is always SOC support inside the CPU and that is delt with inside the P2P subsystem logic. If we ever see a problem it would be delt with by quirking the broken device through pci-quirks and having the p2p subsystem refuse any p2p with that device. Jason
