diff --git a/nova/objects/base.py b/nova/objects/base.py
index 1466e2327085..7b4d3d8d62f9 100644
--- a/nova/objects/base.py
+++ b/nova/objects/base.py
@@ -632,7 +632,7 @@ class NovaObjectSerializer(messaging.NoOpSerializer):
     def _process_object(self, context, objprim):
         try:
             objinst = NovaObject.obj_from_primitive(objprim, context=context)
-        except exception.IncompatibleObjectVersion as e:
+        except exception.IncompatibleObjectVersion:
             objver = objprim['nova_object.version']
             if objver.count('.') == 2:
                 # NOTE(danms): For our purposes, the .z part of the version
@@ -640,8 +640,13 @@ class NovaObjectSerializer(messaging.NoOpSerializer):
                 objprim['nova_object.version'] = \
                     '.'.join(objver.split('.')[:2])
                 return self._process_object(context, objprim)
-            objinst = self.conductor.object_backport(context, objprim,
-                                                     e.kwargs['supported'])
+            objname = objprim['nova_object.name']
+            supported = NovaObjectRegistry.obj_classes().get(objname, [])
+            if supported:
+                objinst = self.conductor.object_backport(context, objprim,
+                                                         supported[0].VERSION)
+            else:
+                raise
         return objinst
 
     def _process_iterable(self, context, action_fn, values):
diff --git a/nova/tests/unit/objects/test_objects.py b/nova/tests/unit/objects/test_objects.py
index 8bc0c4d28792..2280697cee76 100644
--- a/nova/tests/unit/objects/test_objects.py
+++ b/nova/tests/unit/objects/test_objects.py
@@ -986,6 +986,36 @@ class TestObjectSerializer(_BaseTestCase):
         # .0 of the object.
         self.assertEqual('1.6', obj.VERSION)
 
+    def test_nested_backport(self):
+        @base.NovaObjectRegistry.register
+        class Parent(base.NovaObject):
+            VERSION = '1.0'
+
+            fields = {
+                'child': fields.ObjectField('MyObj'),
+            }
+
+        @base.NovaObjectRegistry.register  # noqa
+        class Parent(base.NovaObject):
+            VERSION = '1.1'
+
+            fields = {
+                'child': fields.ObjectField('MyObj'),
+            }
+
+        child = MyObj(foo=1)
+        parent = Parent(child=child)
+        prim = parent.obj_to_primitive()
+        child_prim = prim['nova_object.data']['child']
+        child_prim['nova_object.version'] = '1.10'
+        ser = base.NovaObjectSerializer()
+        with mock.patch.object(ser.conductor, 'object_backport') as backport:
+            ser.deserialize_entity(self.context, prim)
+            # NOTE(danms): This should be the version of the parent object,
+            # not the child. If wrong, this will be '1.6', which is the max
+            # child version in our registry.
+            backport.assert_called_once_with(self.context, prim, '1.1')
+
     def test_object_serialization(self):
         ser = base.NovaObjectSerializer()
         obj = MyObj()