intel-iommu: Fix reference by physical address in intel_iommu_attach_device()

Commit a99c47a2 "intel-iommu: errors with smaller iommu widths" replace the
dmar_domain->pgd with the first entry of page table when iommu's supported
width is smaller than dmar_domain's. But it use physical address directly
for new dmar_domain->pgd...

This result in KVM oops with VT-d on some machines.

Reported-by: Allen Kay <allen.m.kay@intel.com>
Cc: Tom Lyon <pugs@cisco.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 796828fce34cb5b918a485de903d3af18971ed38..3bd30557ce2ebe456ab1adfb26c9bfe2a945cce3 100644 (file)
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -3603,7 +3603,8 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
                pte = dmar_domain->pgd;
                if (dma_pte_present(pte)) {
                        free_pgtable_page(dmar_domain->pgd);
-                       dmar_domain->pgd = (struct dma_pte *)dma_pte_addr(pte);
+                       dmar_domain->pgd = (struct dma_pte *)
+                               phys_to_virt(dma_pte_addr(pte));
                }
                dmar_domain->agaw--;
        }