diff --git a/qa/rpc-tests/maxuploadtarget.py b/qa/rpc-tests/maxuploadtarget.py
index 125d4eb275..d0e9fe9a3f 100755
--- a/qa/rpc-tests/maxuploadtarget.py
+++ b/qa/rpc-tests/maxuploadtarget.py
@@ -75,7 +75,7 @@ class TestNode(NodeConnCB):
         def received_pong():
             return (self.last_pong.nonce == self.ping_counter)
         self.connection.send_message(msg_ping(nonce=self.ping_counter))
-        success = wait_until(received_pong, timeout)
+        success = wait_until(received_pong, timeout=timeout)
         self.ping_counter += 1
         return success
 
diff --git a/qa/rpc-tests/p2p-mempool.py b/qa/rpc-tests/p2p-mempool.py
index 5c5d778f42..382d7f1e82 100755
--- a/qa/rpc-tests/p2p-mempool.py
+++ b/qa/rpc-tests/p2p-mempool.py
@@ -63,7 +63,7 @@ class TestNode(NodeConnCB):
         def received_pong():
             return (self.last_pong.nonce == self.ping_counter)
         self.connection.send_message(msg_ping(nonce=self.ping_counter))
-        success = wait_until(received_pong, timeout)
+        success = wait_until(received_pong, timeout=timeout)
         self.ping_counter += 1
         return success
 
diff --git a/qa/rpc-tests/test_framework/mininode.py b/qa/rpc-tests/test_framework/mininode.py
index 0b7b17cdb5..88a3b7e0f7 100755
--- a/qa/rpc-tests/test_framework/mininode.py
+++ b/qa/rpc-tests/test_framework/mininode.py
@@ -1320,7 +1320,7 @@ class msg_reject(object):
             % (self.message, self.code, self.reason, self.data)
 
 # Helper function
-def wait_until(predicate, attempts=float('inf'), timeout=float('inf')):
+def wait_until(predicate, *, attempts=float('inf'), timeout=float('inf')):
     attempt = 0
     elapsed = 0