diff --git a/lib/utils.py b/lib/utils.py
index 4484085a19ee9018e738b75a37c2ff37df8d074b..cdb02bf7744ad76d0bcda6c12b53918689ec819a 100644
--- a/lib/utils.py
+++ b/lib/utils.py
@@ -1772,7 +1772,7 @@ def Mlockall():
   libc.__errno_location.restype = ctypes.POINTER(ctypes.c_int)
 
   if libc.mlockall(_MCL_CURRENT | _MCL_FUTURE):
-    logging.error("Cannot set memory lock: %s" %
+    logging.error("Cannot set memory lock: %s",
                   os.strerror(libc.__errno_location().contents.value))
     return