diff -r 42e9682e4b61 xen/arch/x86/acpi/boot.c
--- a/xen/arch/x86/acpi/boot.c	Mon Oct 26 13:33:38 2009 +0000
+++ b/xen/arch/x86/acpi/boot.c	Wed Oct 28 11:58:31 2009 +0100
@@ -936,6 +936,8 @@ int __init acpi_boot_init(void)
 
 	acpi_dmar_init();
 
+	acpi_ivrs_init();
+
 	acpi_mmcfg_init();
 
 	return 0;
diff -r 42e9682e4b61 xen/drivers/passthrough/amd/iommu_acpi.c
--- a/xen/drivers/passthrough/amd/iommu_acpi.c	Mon Oct 26 13:33:38 2009 +0000
+++ b/xen/drivers/passthrough/amd/iommu_acpi.c	Wed Oct 28 11:58:31 2009 +0100
@@ -863,6 +863,7 @@ static int __init detect_iommu_acpi(stru
         return -ENODEV;
     }
 
+    INIT_LIST_HEAD(&amd_iommu_head);
     while ( table->length > (length + sizeof(*ivrs_block)) )
     {
         ivrs_block = (struct acpi_ivrs_block_header *) ((u8 *)table + length);
@@ -972,9 +973,23 @@ static int __init get_last_bdf_acpi(stru
    return 0;
 }
 
-int __init amd_iommu_detect_acpi(void)
-{
-    return acpi_table_parse(AMD_IOMMU_ACPI_IVRS_SIG, detect_iommu_acpi);
+int __init acpi_ivrs_init(void)
+{
+    int rt;
+
+    /* to make sure this flag has not been cleared after vtd detection */
+    iommu_enabled = 1;
+
+    rt = acpi_table_parse(AMD_IOMMU_ACPI_IVRS_SIG, detect_iommu_acpi);
+
+    if ( (rt != 0) || (iommu_found() == 0) )
+    {
+        printk("AMD-Vi: IOMMU not found!\n");
+        iommu_enabled = 0;
+        return -ENODEV;
+    }
+
+    return 0;
 }
 
 int __init amd_iommu_get_ivrs_dev_entries(void)
diff -r 42e9682e4b61 xen/drivers/passthrough/amd/iommu_init.c
--- a/xen/drivers/passthrough/amd/iommu_init.c	Mon Oct 26 13:33:38 2009 +0000
+++ b/xen/drivers/passthrough/amd/iommu_init.c	Wed Oct 28 11:58:31 2009 +0100
@@ -628,7 +628,7 @@ error_out:
     return -ENODEV;
 }
 
-static void __init amd_iommu_init_cleanup(void)
+void __init amd_iommu_init_cleanup(void)
 {
     struct amd_iommu *iommu, *next;
     int bdf;
@@ -718,7 +718,7 @@ static int __init amd_iommu_setup_device
     int sys_mgt, dev_ex, lint1_pass, lint0_pass,
        nmi_pass, ext_int_pass, init_pass;
 
-    BUG_ON( (ivrs_bdf_entries == 0) || (iommu_enabled) );
+    BUG_ON( (ivrs_bdf_entries == 0) );
 
     /* allocate 'device table' on a 4K boundary */
     device_table.alloc_size = PAGE_SIZE <<
@@ -805,6 +805,7 @@ int __init amd_iommu_init(void)
 
 error_out:
     amd_iommu_init_cleanup();
+    printk("AMD-Vi: Error initialization!\n");
     return -ENODEV;
 }
 
diff -r 42e9682e4b61 xen/drivers/passthrough/amd/pci_amd_iommu.c
--- a/xen/drivers/passthrough/amd/pci_amd_iommu.c	Mon Oct 26 13:33:38 2009 +0000
+++ b/xen/drivers/passthrough/amd/pci_amd_iommu.c	Wed Oct 28 11:58:31 2009 +0100
@@ -158,24 +158,6 @@ static void amd_iommu_setup_dom0_devices
     spin_unlock(&pcidevs_lock);
 }
 
-int amd_iov_detect(void)
-{
-    INIT_LIST_HEAD(&amd_iommu_head);
-
-    if ( (amd_iommu_detect_acpi() !=0) || (iommu_found() == 0) )
-    {
-        printk("AMD-Vi: IOMMU not found!\n");
-        return -ENODEV;
-    }
-
-    if ( amd_iommu_init() != 0 )
-    {
-        printk("Error initialization\n");
-        return -ENODEV;
-    }
-    return 0;
-}
-
 static int allocate_domain_resources(struct hvm_iommu *hd)
 {
     /* allocate root table */
diff -r 42e9682e4b61 xen/include/asm-x86/acpi.h
--- a/xen/include/asm-x86/acpi.h	Mon Oct 26 13:33:38 2009 +0000
+++ b/xen/include/asm-x86/acpi.h	Wed Oct 28 11:58:31 2009 +0100
@@ -154,6 +154,7 @@ extern u8 x86_acpiid_to_apicid[];
 #define MAX_LOCAL_APIC 256
 
 int acpi_dmar_init(void);
+int acpi_ivrs_init(void);
 void acpi_mmcfg_init(void);
 
 /* Incremented whenever we transition through S3. Value is 1 during boot. */
diff -r 42e9682e4b61 xen/include/asm-x86/hvm/iommu.h
--- a/xen/include/asm-x86/hvm/iommu.h	Mon Oct 26 13:33:38 2009 +0000
+++ b/xen/include/asm-x86/hvm/iommu.h	Wed Oct 28 11:58:31 2009 +0100
@@ -5,7 +5,7 @@ extern struct iommu_ops intel_iommu_ops;
 extern struct iommu_ops intel_iommu_ops;
 extern struct iommu_ops amd_iommu_ops;
 extern int intel_vtd_setup(void);
-extern int amd_iov_detect(void);
+extern int amd_iommu_init(void);
 
 static inline struct iommu_ops *iommu_get_ops(void)
 {   
@@ -29,7 +29,7 @@ static inline int iommu_hardware_setup(v
     case X86_VENDOR_INTEL:
         return intel_vtd_setup();
     case X86_VENDOR_AMD:
-        return amd_iov_detect();
+        return amd_iommu_init();
     default:
         BUG();
     }