diff --git a/python/dune/perftool/pdelab/driver.py b/python/dune/perftool/pdelab/driver.py
index 6bed1ab630fe7e54fed481d504a45af85d78f28a..11c66909900f0189e700d0a24148864585dd1e37 100644
--- a/python/dune/perftool/pdelab/driver.py
+++ b/python/dune/perftool/pdelab/driver.py
@@ -78,7 +78,7 @@ def mass_form_index(formdatas, data):
         try:
             if data.object_names[id(formdata.original_form)] == 'mass':
                 return index
-        except:
+        except KeyError:
             continue