diff --git a/bin/run-fxmark.py b/bin/run-fxmark.py
index a5fe0aa..2092479 100755
--- a/bin/run-fxmark.py
+++ b/bin/run-fxmark.py
@@ -275,7 +275,8 @@ def umount(self, where):
             if p.returncode is not 0:
                 break
         (umount_hook, self.umount_hook) = (self.umount_hook, [])
-        map(lambda hook: hook(), umount_hook);
+        for hook in umount_hook:
+            hook()
 
     def init_mem_disk(self):
         self.unset_loopdev()