diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index c97d35c..f635fb0 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -10,7 +10,7 @@ endif
 EXTRA_CFLAGS += -Ivirt/kvm -Iarch/x86/kvm
 
 kvm-objs := $(common-objs) x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o \
-	i8254.o
+	i8254.o vtd.o
 obj-$(CONFIG_KVM) += kvm.o
 kvm-intel-objs = vmx.o
 obj-$(CONFIG_KVM_INTEL) += kvm-intel.o
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d8bc492..61052e1 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -28,6 +28,7 @@
 #include <linux/module.h>
 #include <linux/mman.h>
 #include <linux/highmem.h>
+#include <linux/pci.h>
 
 #include <asm/uaccess.h>
 #include <asm/msr.h>
@@ -351,6 +352,8 @@ static void kvm_free_pci_passthrough(struct kvm *kvm)
 
 		list_del(&pci_pt_dev->list);
 	}
+	if (kvm_intel_iommu_found())
+		kvm->arch.domain = NULL;
 	write_unlock_irqrestore(&kvm_pci_pt_lock, flags);
 }
 
@@ -1958,6 +1961,11 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		r = kvm_vm_ioctl_pci_pt_dev(kvm, &pci_pt_dev);
 		if (r)
 			goto out;
+		if (kvm_intel_iommu_found()) {
+			r = kvm_iommu_map_guest(kvm, &pci_pt_dev);
+			if (r)
+				goto out;
+		}
 		break;
 	}
 	case KVM_GET_PIT: {
@@ -4213,6 +4221,8 @@ static void kvm_free_vcpus(struct kvm *kvm)
 
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
+	if (kvm_intel_iommu_found())
+		kvm_iommu_unmap_guest(kvm);
 	kvm_free_pci_passthrough(kvm);
 	kvm_free_pit(kvm);
 	kfree(kvm->arch.vpic);
diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
index 496adbf..c1ca2f2 100644
--- a/include/asm-x86/kvm_host.h
+++ b/include/asm-x86/kvm_host.h
@@ -19,6 +19,8 @@
 #include <linux/kvm_types.h>
 
 #include <asm/desc.h>
+#include <linux/dmar.h>
+#include <linux/intel-iommu.h>
 
 #define KVM_MAX_VCPUS 16
 #define KVM_MEMORY_SLOTS 32
@@ -345,6 +347,7 @@ struct kvm_arch{
 	 */
 	struct list_head active_mmu_pages;
 	struct list_head pci_pt_dev_head;
+	struct dmar_domain *domain;
 	struct kvm_pic *vpic;
 	struct kvm_ioapic *vioapic;
 	struct kvm_pit *vpit;
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 4741063..080d0c1 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -272,6 +272,13 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *v);
 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu);
 void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
 
+int kvm_iommu_map_pages(struct kvm *kvm, gfn_t base_gfn,
+			unsigned long npages);
+int kvm_iommu_map_guest(struct kvm *kvm,
+			struct kvm_pci_passthrough_dev *pci_pt_dev);
+int kvm_iommu_unmap_guest(struct kvm *kvm);
+int kvm_intel_iommu_found(void);
+
 static inline void kvm_guest_enter(void)
 {
 	account_system_vtime(current);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index e8f9fda..7211823 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -388,6 +388,11 @@ int __kvm_set_memory_region(struct kvm *kvm,
 	}
 
 	kvm_free_physmem_slot(&old, &new);
+
+	/* map the pages in iommu page table */
+	if (kvm_intel_iommu_found())
+		kvm_iommu_map_pages(kvm, base_gfn, npages);
+
 	return 0;
 
 out_free: