diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 5dc5d3e3508e87a00497895f4773079e96a983b0..cdded1e2e66028271c71535e414712cfe45c9bcc 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1299,7 +1299,7 @@ static void iommu_detach_domain(struct dmar_domain *domain,
 static struct iova_domain reserved_iova_list;
 static struct lock_class_key reserved_rbtree_key;
 
-static void dmar_init_reserved_ranges(void)
+static int dmar_init_reserved_ranges(void)
 {
 	struct pci_dev *pdev = NULL;
 	struct iova *iova;
@@ -1313,8 +1313,10 @@ static void dmar_init_reserved_ranges(void)
 	/* IOAPIC ranges shouldn't be accessed by DMA */
 	iova = reserve_iova(&reserved_iova_list, IOVA_PFN(IOAPIC_RANGE_START),
 		IOVA_PFN(IOAPIC_RANGE_END));
-	if (!iova)
+	if (!iova) {
 		printk(KERN_ERR "Reserve IOAPIC range failed\n");
+		return -ENODEV;
+	}
 
 	/* Reserve all PCI MMIO to avoid peer-to-peer access */
 	for_each_pci_dev(pdev) {
@@ -1327,11 +1329,13 @@ static void dmar_init_reserved_ranges(void)
 			iova = reserve_iova(&reserved_iova_list,
 					    IOVA_PFN(r->start),
 					    IOVA_PFN(r->end));
-			if (!iova)
+			if (!iova) {
 				printk(KERN_ERR "Reserve iova failed\n");
+				return -ENODEV;
+			}
 		}
 	}
-
+	return 0;
 }
 
 static void domain_reserve_special_ranges(struct dmar_domain *domain)
@@ -2213,7 +2217,7 @@ static int __init iommu_prepare_static_identity_mapping(int hw)
 	return 0;
 }
 
-int __init init_dmars(void)
+static int __init init_dmars(int force_on)
 {
 	struct dmar_drhd_unit *drhd;
 	struct dmar_rmrr_unit *rmrr;
@@ -2393,8 +2397,15 @@ int __init init_dmars(void)
 	 *   enable translation
 	 */
 	for_each_drhd_unit(drhd) {
-		if (drhd->ignored)
+		if (drhd->ignored) {
+			/*
+			 * we always have to disable PMRs or DMA may fail on
+			 * this device
+			 */
+			if (force_on)
+				iommu_disable_protect_mem_regions(drhd->iommu);
 			continue;
+		}
 		iommu = drhd->iommu;
 
 		iommu_flush_write_buffer(iommu);
@@ -3303,12 +3314,21 @@ int __init intel_iommu_init(void)
 	if (no_iommu || dmar_disabled)
 		return -ENODEV;
 
-	iommu_init_mempool();
-	dmar_init_reserved_ranges();
+	if (iommu_init_mempool()) {
+		if (force_on)
+			panic("tboot: Failed to initialize iommu memory\n");
+		return 	-ENODEV;
+	}
+
+	if (dmar_init_reserved_ranges()) {
+		if (force_on)
+			panic("tboot: Failed to reserve iommu ranges\n");
+		return 	-ENODEV;
+	}
 
 	init_no_remapping_devices();
 
-	ret = init_dmars();
+	ret = init_dmars(force_on);
 	if (ret) {
 		if (force_on)
 			panic("tboot: Failed to initialize DMARs\n");