From 184bee388d4661c3fea633f135a5c45ff03c7ec6 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Mon, 2 Sep 2024 10:27:11 +0800 Subject: [PATCH] iommu/vt-d: Require DMA domain if hardware not support passthrough The iommu core defines the def_domain_type callback to query the iommu driver about hardware capability and quirks. The iommu driver should declare IOMMU_DOMAIN_DMA requirement for hardware lacking pass-through capability. Earlier VT-d hardware implementations did not support pass-through translation mode. The iommu driver relied on a paging domain with all physical system memory addresses identically mapped to the same IOVA to simulate pass-through translation before the def_domain_type was introduced and it has been kept until now. It's time to adjust it now to make the Intel iommu driver follow the def_domain_type semantics. Signed-off-by: Lu Baolu Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Reviewed-by: Jerry Snitselaar Link: https://lore.kernel.org/r/20240809055431.36513-2-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel --- drivers/iommu/intel/iommu.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 9ff8b83c19a3e..90ad794a1be73 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2149,6 +2149,16 @@ static bool device_rmrr_is_relaxable(struct device *dev) static int device_def_domain_type(struct device *dev) { + struct device_domain_info *info = dev_iommu_priv_get(dev); + struct intel_iommu *iommu = info->iommu; + + /* + * Hardware does not support the passthrough translation mode. + * Always use a dynamaic mapping domain. + */ + if (!ecap_pass_through(iommu->ecap)) + return IOMMU_DOMAIN_DMA; + if (dev_is_pci(dev)) { struct pci_dev *pdev = to_pci_dev(dev);