On Mon, Jan 13, 2025 at 11:34:44AM +0800, Chenyi Qiang wrote: > > > On 1/10/2025 5:50 AM, Xu Yilun wrote: > > On Fri, Jan 10, 2025 at 05:00:22AM +0800, Xu Yilun wrote: > >>>> > >>>> https://github.com/aik/qemu/commit/3663f889883d4aebbeb0e4422f7be5e357e2ee46 > >>>> > >>>> but I am not sure if this ever saw the light of the day, did not it? > >>>> (ironically I am using it as a base for encrypted DMA :) ) > >>> > >>> Yeah, we are doing the same work. I saw a solution from Michael long > >>> time ago (when there was still > >>> a dedicated hostmem-memfd-private backend for restrictedmem/gmem) > >>> (https://github.com/AMDESE/qemu/commit/3bf5255fc48d648724d66410485081ace41d8ee6) > >>> > >>> For your patch, it only implement the interface for > >>> HostMemoryBackendMemfd. Maybe it is more appropriate to implement it for > >>> the parent object HostMemoryBackend, because besides the > >>> MEMORY_BACKEND_MEMFD, other backend types like MEMORY_BACKEND_RAM and > >>> MEMORY_BACKEND_FILE can also be guest_memfd-backed. > >>> > >>> Think more about where to implement this interface. It is still > >>> uncertain to me. As I mentioned in another mail, maybe ram device memory > >>> region would be backed by guest_memfd if we support TEE IO iommufd MMIO > >> > >> It is unlikely an assigned MMIO region would be backed by guest_memfd or be > >> implemented as part of HostMemoryBackend. Nowadays assigned MMIO resource is > >> owned by VFIO types, and I assume it is still true for private MMIO. > >> > >> But I think with TIO, MMIO regions also need conversion. So I support an > >> object, but maybe not guest_memfd_manager. > > > > Sorry, I mean the name only covers private memory, but not private MMIO. > > So you suggest renaming the object to cover the private MMIO. Then how Yes. > about page_conversion_manager, or page_attribute_manager? Maybe memory_attribute_manager? Strictly speaking MMIO resource is not backed by pages. Thanks, Yilun > > > > >> > >> Thanks, > >> Yilun > >> > >>> in future. Then a specific object is more appropriate. What's your opinion? > >>> > >> >
