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>>> >>> + if (!dev_is_pci(dev)) >>> + return 0; >>> + >>> /* Always use DMA domain for untrusted device */ >>> - if (dev_is_pci(dev) && to_pci_dev(dev)->untrusted) >>> + if (to_pci_dev(dev)->untrusted) >>> return IOMMU_DOMAIN_DMA; >> >> The core code does this, it shouldn't be in a driver? > > Right. I didn't realized core has this check. I will drop this check in next > version. > >> >>> - /* >>> - * Do not identity map IOMMUv2 capable devices when: >>> - * - memory encryption is active, because some of those devices >>> - * (AMD GPUs) don't have the encryption bit in their DMA-mask >>> - * and require remapping. >>> - * - SNP is enabled, because it prohibits DTE[Mode]=0. >>> - */ >>> - if (pdev_pasid_supported(dev_data) && >>> - !cc_platform_has(CC_ATTR_MEM_ENCRYPT) && >>> - !amd_iommu_snp_en) { >>> + /* Apply device specific quirks */ >>> + if (quirks_force_identity_mapping(to_pci_dev(dev))) { >>> + >>> + /* >>> + * When memory encryption is active, some of these devices >>> + * don't have the encryption bit in their DMA-mask and >>> + * require remapping. >>> + */ >>> + if (cc_platform_has(CC_ATTR_MEM_ENCRYPT)) >>> + return 0; >> >> I think this can probably be dropped now? There is no intersection of >> this old broken embedded GPU and a CPU that supports CC right? > > > I did consider dropping these two checks, but I was not entirely sure. So I kept > as is for now. Once these series settles and I can go with next step of dropping > these two checks. > > @Alex, @Mario, Any suggestions ? > The background comes from this series: https://lore.kernel.org/all/20200824105415.21000-1-joro@8bytes.org/ > -Vasant > >> >>> + >>> + /* DTE[Mode]=0 is prohibited when SNP is enabled */ >>> + if (amd_iommu_snp_en) >>> + return 0; >> >> Ditto? >> >> Jason >