diff --git a/nova/objects/base.py b/nova/objects/base.py
index 666e82f80d58..a5ab15e8ad30 100644
--- a/nova/objects/base.py
+++ b/nova/objects/base.py
@@ -17,6 +17,7 @@
 import collections
 import copy
 import functools
+import traceback
 
 import netaddr
 from oslo import messaging
@@ -704,3 +705,22 @@ def obj_make_list(context, list_obj, item_cls, db_list, **extra_args):
     list_obj._context = context
     list_obj.obj_reset_changes()
     return list_obj
+
+
+def serialize_args(fn):
+    """Decorator that will do the arguments serialization before remoting."""
+    def wrapper(cls, *args, **kwargs):
+        for kw in kwargs:
+            value_arg = kwargs.get(kw)
+            if kw == 'exc_val' and value_arg:
+                kwargs[kw] = str(value_arg)
+            if kw == 'exc_tb' and (
+                    not isinstance(value_arg, six.string_types) and value_arg):
+                kwargs[kw] = ''.join(traceback.format_tb(value_arg))
+        # NOTE(danms): We wrap a descriptor, so use that protocol
+        return fn.__get__(None, cls)(*args, **kwargs)
+
+    # NOTE(danms): Make this discoverable
+    wrapper.remotable = getattr(fn, 'remotable', False)
+    wrapper.original_fn = fn
+    return classmethod(wrapper)
diff --git a/nova/objects/instance_action.py b/nova/objects/instance_action.py
index 076594659b27..1501c441dc07 100644
--- a/nova/objects/instance_action.py
+++ b/nova/objects/instance_action.py
@@ -12,10 +12,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import traceback
-
-import six
-
 from nova import db
 from nova import objects
 from nova.objects import base
@@ -112,19 +108,6 @@ class InstanceActionList(base.ObjectListBase, base.NovaObject):
         return base.obj_make_list(context, cls(), InstanceAction, db_actions)
 
 
-def serialize_args(fn):
-    def wrapper(cls, *args, **kwargs):
-        exc_val = kwargs.get('exc_val')
-        exc_tb = kwargs.get('exc_tb')
-        if exc_val is not None:
-            kwargs['exc_val'] = six.text_type(exc_val)
-        if not isinstance(exc_tb, six.string_types) and exc_tb is not None:
-            kwargs['exc_tb'] = ''.join(traceback.format_tb(exc_tb))
-        # NOTE(danms): We wrap a descriptor, so use that protocol
-        return fn.__get__(None, cls)(*args, **kwargs)
-    return classmethod(wrapper)
-
-
 class InstanceActionEvent(base.NovaPersistentObject, base.NovaObject):
     # Version 1.0: Initial version
     # Version 1.1: event_finish_with_failure decorated with serialize_args
@@ -183,7 +166,7 @@ class InstanceActionEvent(base.NovaPersistentObject, base.NovaObject):
         if want_result:
             return cls._from_db_object(context, cls(), db_event)
 
-    @serialize_args
+    @base.serialize_args
     @base.remotable_classmethod
     def event_finish_with_failure(cls, context, instance_uuid, event_name,
                                   exc_val=None, exc_tb=None, want_result=None):
diff --git a/nova/tests/objects/test_objects.py b/nova/tests/objects/test_objects.py
index e5c729c1634e..ce5d59980e30 100644
--- a/nova/tests/objects/test_objects.py
+++ b/nova/tests/objects/test_objects.py
@@ -950,7 +950,7 @@ object_data = {
     'FloatingIPList': '1.2-6c5b0b4d4a4c17575f4d91bae14e5237',
     'Instance': '1.13-c9cfd71ddc9d6e7e7c72879f4d5982ee',
     'InstanceAction': '1.1-6b1d0a6dbd522b5a83c20757ec659663',
-    'InstanceActionEvent': '1.1-f144eaa9fb22f248fc41ed8401a3a1be',
+    'InstanceActionEvent': '1.1-42dbdba74bd06e0619ca75cd3397cd1b',
     'InstanceActionEventList': '1.0-1d5cc958171d6ce07383c2ad6208318e',
     'InstanceActionList': '1.0-368410fdb8d69ae20c495308535d6266',
     'InstanceExternalEvent': '1.0-f1134523654407a875fd59b80f759ee7',
@@ -1005,6 +1005,21 @@ class TestObjectVersions(test.TestCase):
     def setUp(self):
         super(TestObjectVersions, self).setUp()
 
+    def _find_remotable_method(self, cls, thing, parent_was_remotable=False):
+        """Follow a chain of remotable things down to the original function."""
+        if isinstance(thing, classmethod):
+            return self._find_remotable_method(cls, thing.__get__(None, cls))
+        elif inspect.ismethod(thing) and hasattr(thing, 'remotable'):
+            return self._find_remotable_method(cls, thing.original_fn,
+                                               parent_was_remotable=True)
+        elif parent_was_remotable:
+            # We must be the first non-remotable thing underneath a stack of
+            # remotable things (i.e. the actual implementation method)
+            return thing
+        else:
+            # This means the top-level thing never hit a remotable layer
+            return None
+
     def _get_fingerprint(self, obj_name):
         obj_class = base.NovaObject._obj_classes[obj_name][0]
         fields = obj_class.fields.items()
@@ -1012,8 +1027,10 @@ class TestObjectVersions(test.TestCase):
         methods = []
         for name in dir(obj_class):
             thing = getattr(obj_class, name)
-            if inspect.ismethod(thing) and hasattr(thing, 'remotable'):
-                methods.append((name, inspect.getargspec(thing.original_fn)))
+            if inspect.ismethod(thing) or isinstance(thing, classmethod):
+                method = self._find_remotable_method(obj_class, thing)
+                if method:
+                    methods.append((name, inspect.getargspec(method)))
         methods.sort()
         # NOTE(danms): Things that need a version bump are any fields
         # and their types, or the signatures of any remotable methods.