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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 ? -Vasant > >> + >> + /* DTE[Mode]=0 is prohibited when SNP is enabled */ >> + if (amd_iommu_snp_en) >> + return 0; > > Ditto? > > Jason