On Fri, Mar 12, 2021 at 06:17:55PM +0530, Vivek Kumar Gautam wrote: > > Regarding the overall design, I was initially assigning page directories > > instead of whole PASID tables, which would simplify the driver and host > > implementation. A major complication, however, is SMMUv3 accesses PASID > > tables using a guest-physical address, so there is a messy negotiation > > needed between host and guest when the host needs to allocate PASID > > tables. Plus vSMMU needs PASID table assignment, so that's what the host > > driver will implement. > > By assigning the page directories, you mean setting up just the stage-1 page > table ops, and passing that information to the host using ATTACH_TABLE? Yes. And we can support nested translation with SMMUv2 that way. But with SMMUv3 the guest has to manage the whole PASID table. > Right now when using kvmtool, the struct iommu_pasid_table_config is > populated with the correct information, and this whole memory is mapped > between host and guest by creating a mem bank using > kvm__for_each_mem_bank(). > Did I get you or did I fail terribly in understanding the point you are > making here? Makes sense Thanks, Jean _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
