diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 825d80130bd435fe50830c8ae5b7905d18104dd6..e8ddf92bb18547f0d3b811b3d757cbae7fec8b8d 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -84,6 +84,8 @@ typedef struct VFIOContainer {
     QLIST_HEAD(, VFIOGroup) group_list;
 } VFIOContainer;
 
+OBJECT_DECLARE_SIMPLE_TYPE(VFIOContainer, VFIO_IOMMU_LEGACY);
+
 typedef struct VFIOHostDMAWindow {
     hwaddr min_iova;
     hwaddr max_iova;
@@ -99,6 +101,8 @@ typedef struct VFIOIOMMUFDContainer {
     uint32_t ioas_id;
 } VFIOIOMMUFDContainer;
 
+OBJECT_DECLARE_SIMPLE_TYPE(VFIOIOMMUFDContainer, VFIO_IOMMU_IOMMUFD);
+
 typedef struct VFIODeviceOps VFIODeviceOps;
 
 typedef struct VFIODevice {
diff --git a/include/hw/vfio/vfio-container-base.h b/include/hw/vfio/vfio-container-base.h
index d505f63607ec40e6aa44aeb3e20848ac780562a1..b079b76f68975c5701a289ce9012e912a8e44fc6 100644
--- a/include/hw/vfio/vfio-container-base.h
+++ b/include/hw/vfio/vfio-container-base.h
@@ -34,6 +34,7 @@ typedef struct VFIOAddressSpace {
  * This is the base object for vfio container backends
  */
 typedef struct VFIOContainerBase {
+    Object parent;
     const VFIOIOMMUClass *ops;
     VFIOAddressSpace *space;
     MemoryListener listener;
@@ -96,17 +97,10 @@ void vfio_container_destroy(VFIOContainerBase *bcontainer);
 #define TYPE_VFIO_IOMMU_SPAPR TYPE_VFIO_IOMMU "-spapr"
 #define TYPE_VFIO_IOMMU_IOMMUFD TYPE_VFIO_IOMMU "-iommufd"
 
-/*
- * VFIOContainerBase is not an abstract QOM object because it felt
- * unnecessary to expose all the IOMMU backends to the QEMU machine
- * and human interface. However, we can still abstract the IOMMU
- * backend handlers using a QOM interface class. This provides more
- * flexibility when referencing the various implementations.
- */
-DECLARE_CLASS_CHECKERS(VFIOIOMMUClass, VFIO_IOMMU, TYPE_VFIO_IOMMU)
+OBJECT_DECLARE_TYPE(VFIOContainerBase, VFIOIOMMUClass, VFIO_IOMMU)
 
 struct VFIOIOMMUClass {
-    InterfaceClass parent_class;
+    ObjectClass parent_class;
 
     /* Properties */
     const char *hiod_typename;
diff --git a/hw/vfio/container-base.c b/hw/vfio/container-base.c
index 280f0dd2db1fc3939fe9925ce00a2c50d0e14196..98c15e174dd78df5146ee83c05c98f3ea9c1e52c 100644
--- a/hw/vfio/container-base.c
+++ b/hw/vfio/container-base.c
@@ -102,8 +102,10 @@ void vfio_container_destroy(VFIOContainerBase *bcontainer)
 static const TypeInfo types[] = {
     {
         .name = TYPE_VFIO_IOMMU,
-        .parent = TYPE_INTERFACE,
+        .parent = TYPE_OBJECT,
+        .instance_size = sizeof(VFIOContainerBase),
         .class_size = sizeof(VFIOIOMMUClass),
+        .abstract = true,
     },
 };
 
diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index 31bdc46a96d1626b237227a25007957e1d472757..3ae52530a9b500bd53ec9f9e66c73253d97c9aba 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -1196,6 +1196,7 @@ static const TypeInfo types[] = {
     {
         .name = TYPE_VFIO_IOMMU_LEGACY,
         .parent = TYPE_VFIO_IOMMU,
+        .instance_size = sizeof(VFIOContainer),
         .class_init = vfio_iommu_legacy_class_init,
     }, {
         .name = TYPE_HOST_IOMMU_DEVICE_LEGACY_VFIO,
diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index e5d9334142418514215528b9523f12c031792c7f..3e9d642034c2d2234ea701952c94a78ab32e9147 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -672,6 +672,7 @@ static const TypeInfo types[] = {
     {
         .name = TYPE_VFIO_IOMMU_IOMMUFD,
         .parent = TYPE_VFIO_IOMMU,
+        .instance_size = sizeof(VFIOIOMMUFDContainer),
         .class_init = vfio_iommu_iommufd_class_init,
     }, {
         .name = TYPE_HOST_IOMMU_DEVICE_IOMMUFD_VFIO,
diff --git a/hw/vfio/spapr.c b/hw/vfio/spapr.c
index 47b040f1bcca7dd0b5cf052d941b43541e98a3c5..018bd2048194a6a2db83ed740025a7060181698f 100644
--- a/hw/vfio/spapr.c
+++ b/hw/vfio/spapr.c
@@ -30,6 +30,8 @@ typedef struct VFIOSpaprContainer {
     QLIST_HEAD(, VFIOHostDMAWindow) hostwin_list;
 } VFIOSpaprContainer;
 
+OBJECT_DECLARE_SIMPLE_TYPE(VFIOSpaprContainer, VFIO_IOMMU_SPAPR);
+
 static bool vfio_prereg_listener_skipped_section(MemoryRegionSection *section)
 {
     if (memory_region_is_iommu(section->mr)) {
@@ -548,6 +550,7 @@ static const TypeInfo types[] = {
     {
         .name = TYPE_VFIO_IOMMU_SPAPR,
         .parent = TYPE_VFIO_IOMMU_LEGACY,
+        .instance_size = sizeof(VFIOSpaprContainer),
         .class_init = vfio_iommu_spapr_class_init,
     },
 };
