2 files changed, 12 insertions, 3 deletions

diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index 25a00ce4f24d..fa3a11365ec3 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -173,12 +173,21 @@ dmar_parse_one_drhd(struct acpi_dmar_header *header)
         struct dmar_drhd_unit *dmaru;
         int ret = 0;
 
+        drhd = (struct acpi_dmar_hardware_unit *)header;
+        if (!drhd->address) {
+                /* Promote an attitude of violence to a BIOS engineer today */
+                WARN(1, "Your BIOS is broken; DMAR reported at address zero!\n"
+                     "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+                     dmi_get_system_info(DMI_BIOS_VENDOR),
+                     dmi_get_system_info(DMI_BIOS_VERSION),
+                     dmi_get_system_info(DMI_PRODUCT_VERSION));
+                return -ENODEV;
+        }
         dmaru = kzalloc(sizeof(*dmaru), GFP_KERNEL);
         if (!dmaru)
                 return -ENOMEM;
 
         dmaru->hdr = header;
-        drhd = (struct acpi_dmar_hardware_unit *)header;
         dmaru->reg_base_addr = drhd->address;
         dmaru->segment = drhd->segment;
         dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index fb3a3f3fca7a..001b328adf80 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -733,8 +733,8 @@ static void dma_pte_clear_range(struct dmar_domain *domain, u64 start, u64 end)
         start &= (((u64)1) << addr_width) - 1;
         end &= (((u64)1) << addr_width) - 1;
         /* in case it's partial page */
-        start = PAGE_ALIGN(start);
-        end &= PAGE_MASK;
+        start &= PAGE_MASK;
+        end = PAGE_ALIGN(end);
         npages = (end - start) / VTD_PAGE_SIZE;
 
         /* we don't need lock here, nobody else touches the iova range */