diff --git a/tests/qemu-iotests/nbd-fault-injector.py b/tests/qemu-iotests/nbd-fault-injector.py
index 78f42c4214..6e11ef89b8 100755
--- a/tests/qemu-iotests/nbd-fault-injector.py
+++ b/tests/qemu-iotests/nbd-fault-injector.py
@@ -227,7 +227,7 @@ def parse_config(config):
 def load_rules(filename):
     config = configparser.RawConfigParser()
     with open(filename, 'rt') as f:
-        config.readfp(f, filename)
+        config.read_file(f, filename)
     return parse_config(config)
 
 def open_socket(path):