diff --git a/qubesmanager/appmenu_select.py b/qubesmanager/appmenu_select.py
index b14c487..f241fc6 100755
--- a/qubesmanager/appmenu_select.py
+++ b/qubesmanager/appmenu_select.py
@@ -38,7 +38,7 @@ class AppListWidgetItem(PyQt4.QtGui.QListWidgetItem):
 
 
 class AppmenuSelectManager:
-    def __init__(self, vm, apps_multiselect, parent=None):
+    def __init__(self, vm, apps_multiselect):
         self.vm = vm
         self.app_list = apps_multiselect # this is a multiselect wiget
         self.whitelisted = None
diff --git a/qubesmanager/firewall.py b/qubesmanager/firewall.py
index ed60ded..6992afa 100644
--- a/qubesmanager/firewall.py
+++ b/qubesmanager/firewall.py
@@ -409,14 +409,14 @@ class QubesFirewallRulesModel(QtCore.QAbstractItemModel):
 
         return self.createIndex(row, column, self.children[row])
 
-    def parent(self, child):
+    def parent(self, child): # pylint: disable=unused-argument
         return QtCore.QModelIndex()
 
-    # pylint: disable=invalid-name
+    # pylint: disable=invalid-name,unused-argument
     def rowCount(self, parent=QtCore.QModelIndex()):
         return len(self)
 
-    # pylint: disable=invalid-name
+    # pylint: disable=invalid-name,unused-argument
     def columnCount(self, parent=QtCore.QModelIndex()):
         return len(self.__column_names)
 
diff --git a/qubesmanager/multiselectwidget.py b/qubesmanager/multiselectwidget.py
index 24e657a..9754847 100644
--- a/qubesmanager/multiselectwidget.py
+++ b/qubesmanager/multiselectwidget.py
@@ -9,7 +9,7 @@ class MultiSelectWidget(
     __pyqtSignals__ = ("items_removed(PyQt_PyObject)",)
 
     def __init__(self, parent=None):
-        super(MultiSelectWidget, self).__init__()
+        super(MultiSelectWidget, self).__init__(parent)
         self.setupUi(self)
         self.add_selected_button.clicked.connect(self.add_selected)
         self.add_all_button.clicked.connect(self.add_all)
diff --git a/qubesmanager/settings.py b/qubesmanager/settings.py
index 5374e40..b5faa3d 100755
--- a/qubesmanager/settings.py
+++ b/qubesmanager/settings.py
@@ -874,7 +874,7 @@ class VMSettingsWindow(ui_settingsdlg.Ui_SettingsDialog, QtGui.QDialog):
     def set_allow(self, allow):
         self.policy_allow_radio_button.setChecked(allow)
         self.policy_deny_radio_button.setChecked(not allow)
-        self.policy_changed(allow)
+        self.policy_changed()
 
     def policy_changed(self):
         self.rulesTreeView.setEnabled(