From eea53c5816889ee8b64544fa2e9311a81184ff9c Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Sat, 20 Mar 2021 10:54:12 +0800 Subject: iommu/vt-d: Remove WO permissions on second-level paging entries 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 --- drivers/iommu/intel/iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/iommu/intel') diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 0ee5f1bd8af2..b0f901ee6358 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2312,8 +2312,9 @@ __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; -- cgit v1.2.3