diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index dae124872e..374a8f6077 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -360,12 +360,9 @@ def log(msg, filters=(), indent=None):
     for flt in filters:
         msg = flt(msg)
     if isinstance(msg, (dict, list)):
-        # Python < 3.4 needs to know not to add whitespace when pretty-printing:
-        separators = (', ', ': ') if indent is None else (',', ': ')
         # Don't sort if it's already sorted
         do_sort = not isinstance(msg, OrderedDict)
-        print(json.dumps(msg, sort_keys=do_sort,
-                         indent=indent, separators=separators))
+        print(json.dumps(msg, sort_keys=do_sort, indent=indent))
     else:
         print(msg)