diff --git a/synapse/server_notices/worker_server_notices_sender.py b/synapse/server_notices/worker_server_notices_sender.py
index 25abb4ccf..4a133026c 100644
--- a/synapse/server_notices/worker_server_notices_sender.py
+++ b/synapse/server_notices/worker_server_notices_sender.py
@@ -32,7 +32,7 @@ class WorkerServerNoticesSender(object):
         Returns:
             Deferred
         """
-        return defer.succeed()
+        return defer.succeed(None)
 
     def on_user_ip(self, user_id):
         """Called on the master when a worker process saw a client request.