On Wed, Oct 16, 2024 at 07:49:31PM -0400, Peter Xu wrote: > On Wed, Oct 16, 2024 at 07:51:57PM -0300, Jason Gunthorpe wrote: > > On Wed, Oct 16, 2024 at 04:16:17PM -0400, Peter Xu wrote: > > > > > > Is there chance that when !CoCo will be supported, then external modules > > > (e.g. VFIO) can reuse the old user mappings, just like before gmemfd? > > > > > > To support CoCo, I understand gmem+offset is required all over the places. > > > However in a non-CoCo context, I wonder whether the other modules are > > > required to stick with gmem+offset, or they can reuse the old VA ways, > > > because how it works can fundamentally be the same as before, except that > > > the folios now will be managed by gmemfd. > > > > My intention with iommufd was to see fd + offest as the "new" way > > to refer to all guest memory and discourage people from using VMA > > handles. > > Does it mean anonymous memory guests will not be supported at all for > iommufd?
No, they can use the "old" way with normal VMA's still, or they can use an anonymous memfd with the new way.. I just don't expect to have new complex stuff built on the VMA interface - I don't expect guestmemfd VMAs to work. Jason