intel-iommu: Mask physical address to correct page size in intel_map_single()

The physical address passed to domain_pfn_mapping() should be rounded 
down to the start of the MM page, not the VT-d page.

This issue causes kernel panic on PAGE_SIZE>VTD_PAGE_SIZE platforms e.g. ia64
platforms.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 11b317a78b49..af7ff9b5aed8 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -2551,6 +2551,7 @@ static dma_addr_t __intel_map_single(struct device *hwdev, phys_addr_t paddr,
         int prot = 0;
         int ret;
         struct intel_iommu *iommu;
+        unsigned long paddr_pfn = paddr >> PAGE_SHIFT;
 
         BUG_ON(dir == DMA_NONE);
 
@@ -2585,7 +2586,7 @@ static dma_addr_t __intel_map_single(struct device *hwdev, phys_addr_t paddr,
          * is not a big problem
          */
         ret = domain_pfn_mapping(domain, mm_to_dma_pfn(iova->pfn_lo),
-                                 paddr >> VTD_PAGE_SHIFT, size, prot);
+                                 mm_to_dma_pfn(paddr_pfn), size, prot);
         if (ret)
                 goto error;