From ee2c2247690c8bf27d4584fdebfd9b58d74495ee Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Wed, 22 Nov 2023 11:26:04 +0800 Subject: [PATCH] iommu/vt-d: Disable PCI ATS in legacy passthrough mode [ Upstream commit da37dddcf4caf015c400a930301d2ee27a7a15fb ] 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 Signed-off-by: Sasha Levin --- drivers/iommu/intel/iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index de76272d0fb0..807abf4707be 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2517,7 +2517,8 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev) 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; }