From c848416cc05afc1589edba04fe00b85c2f797ee3 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Sat, 20 Mar 2021 10:54:12 +0800 Subject: [PATCH] iommu/vt-d: Remove WO permissions on second-level paging entries [ Upstream commit eea53c5816889ee8b64544fa2e9311a81184ff9c ] When the first level page table is used for IOVA translation, it only supports Read-Only and Read-Write permissions. The Write-Only permission is not supported as the PRESENT bit (implying Read permission) should always set. When using second level, we still give separate permissions that allows WriteOnly which seems inconsistent and awkward. We want to have consistent behavior. After moving to 1st level, we don't want things to work sometimes, and break if we use 2nd level for the same mappings. Hence remove this configuration. Suggested-by: Ashok Raj Fixes: b802d070a52a1 ("iommu/vt-d: Use iova over first level") Signed-off-by: Lu Baolu Link: https://lore.kernel.org/r/20210320025415.641201-3-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 8010c3895f8c..30c2b52f7ea2 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2357,8 +2357,9 @@ static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn, return -EINVAL; attr = prot & (DMA_PTE_READ | DMA_PTE_WRITE | DMA_PTE_SNP); + attr |= DMA_FL_PTE_PRESENT; if (domain_use_first_level(domain)) { - attr |= DMA_FL_PTE_PRESENT | DMA_FL_PTE_XD | DMA_FL_PTE_US; + attr |= DMA_FL_PTE_XD | DMA_FL_PTE_US; if (domain->domain.type == IOMMU_DOMAIN_DMA) { attr |= DMA_FL_PTE_ACCESS;