On 17/07/2026 14:32, Jason Gunthorpe wrote: > On Fri, Jul 17, 2026 at 12:33:17PM +0100, Will Deacon wrote: > >> first. So, at the moment, this just looks like a burden to me, especially >> as it appears to create a brand new, device-specific UAPI for what is >> ostensibly a form of SVA - something which the community is actively >> working on already. > > Yeah, I think it was a mistake to hardwire the invalidation to the > CPU. It would fit much better into Linux if the invalidation was > separate and independently controllable with an option to follow the > CPU.
Well I'm certainly not going to disagree, but the HW is somewhat fixed at this point :-| > > Then you could use a normal S2 page table through iommufd and not mess > with kvm. (though the VMID sharing with KVM for a BTM-like scheme was > never solved upstream) > > I also wouldn't expect you to use vfio-mdev, if the devices are > discovered and known at boot then it should be a normal vfio driver. OK good feedback - I'm not going to claim to be a VFIO expert (especially not in front of an actual VFIO expert) - We'll look closer at this and come back if we have questions (although unlikely over the summer holiday). Thanks, Ryan > > Jason
