From: Lu Baolu Date: Wed, 22 Nov 2023 03:26:04 +0000 (+0800) Subject: iommu/vt-d: Disable PCI ATS in legacy passthrough mode X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=da37dddcf4caf015c400a930301d2ee27a7a15fb;p=linux.git iommu/vt-d: Disable PCI ATS in legacy passthrough mode When IOMMU hardware operates in legacy mode, the TT field of the context entry determines the translation type, with three supported types (Section 9.3 Context Entry): - DMA translation without device TLB support - DMA translation with device TLB support - Passthrough mode with translated and translation requests blocked Device TLB support is absent when hardware is configured in passthrough mode. Disable the PCI ATS feature when IOMMU is configured for passthrough translation type in legacy (non-scalable) mode. Fixes: 0faa19a1515f ("iommu/vt-d: Decouple PASID & PRI enabling from SVA") Signed-off-by: Lu Baolu Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20231114011036.70142-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel --- diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 11670cd812a35..9bddd4fbbdf8c 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2492,7 +2492,8 @@ static int dmar_domain_attach_device(struct dmar_domain *domain, return ret; } - iommu_enable_pci_caps(info); + if (sm_supported(info->iommu) || !domain_type_is_si(info->domain)) + iommu_enable_pci_caps(info); return 0; }