On 09.02.2021 16:28, Julien Grall wrote: > From: Julien Grall <jgr...@amazon.com> > > The new per-domain IOMMU page-table allocator will now free the > page-tables when domain's resources are relinquished. However, the root > page-table (i.e. hd->arch.pg_maddr) will not be cleared. > > Xen may access the IOMMU page-tables afterwards at least in the case of > PV domain: > > (XEN) Xen call trace: > (XEN) [<ffff82d04025b4b2>] R iommu.c#addr_to_dma_page_maddr+0x12e/0x1d8 > (XEN) [<ffff82d04025b695>] F iommu.c#intel_iommu_unmap_page+0x5d/0xf8 > (XEN) [<ffff82d0402695f3>] F iommu_unmap+0x9c/0x129 > (XEN) [<ffff82d0402696a6>] F iommu_legacy_unmap+0x26/0x63
So if unmap was (also) short-circuited for dying domains, this path wouldn't be taken and all would be well even without this change? Jan
