iommu/vt-d: Fix a bug in intel_iommu_iova_to_phys() for huge page

commit 77a1bce84bba01f3f143d77127b72e872b573795 upstream.

intel_iommu_iova_to_phys() has a bug when it translates an IOVA for a huge
page onto its corresponding physical address. This commit fixes the bug by
accomodating the level of page entry for the IOVA and adds IOVA's lower
address to the physical address.

Cc: <stable@vger.kernel.org>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Yonghyun Hwang <yonghyun@google.com>
Fixes: 3871794642579 ("VT-d: Changes to support KVM")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index b8aa5e60e4c3cdebd19f1c319369c6b62c7f3535..db1b546134f5944ceffa7445740f4677f9e3e424 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5124,8 +5124,10 @@ static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
        u64 phys = 0;
 
        pte = pfn_to_dma_pte(dmar_domain, iova >> VTD_PAGE_SHIFT, &level);
-       if (pte)
-               phys = dma_pte_addr(pte);
+       if (pte && dma_pte_present(pte))
+               phys = dma_pte_addr(pte) +
+                       (iova & (BIT_MASK(level_to_offset_bits(level) +
+                                               VTD_PAGE_SHIFT) - 1));
 
        return phys;
 }