diff --git a/HACKING.rst b/HACKING.rst
index cf274bf0..fb9832f3 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -9,6 +9,8 @@ Nova-PowerVM Specific Commandments
 ----------------------------------
 - Follow the Nova HACKING.rst
 
+- [P301] LOG.warn() is not allowed. Use LOG.warning()
+
 Creating Unit Tests
 -------------------
 For every new feature, unit tests should be created that both test and
diff --git a/nova_powervm/hacking/__init__.py b/nova_powervm/hacking/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/nova_powervm/hacking/checks.py b/nova_powervm/hacking/checks.py
new file mode 100644
index 00000000..63d47652
--- /dev/null
+++ b/nova_powervm/hacking/checks.py
@@ -0,0 +1,30 @@
+# Copyright 2016 IBM Corp.
+#
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from nova.hacking import checks
+
+
+def no_log_warn(logical_line, filename):
+    """Disallow 'LOG.warn('
+
+    """
+    if logical_line.startswith('LOG.warn('):
+        yield(0, 'P301 Use LOG.warning() rather than LOG.warn()')
+
+
+def factory(register):
+    register(no_log_warn)
+    checks.factory(register)
diff --git a/nova_powervm/tests/virt/powervm/test_host.py b/nova_powervm/tests/virt/powervm/test_host.py
index 8cc04e04..0f60287e 100644
--- a/nova_powervm/tests/virt/powervm/test_host.py
+++ b/nova_powervm/tests/virt/powervm/test_host.py
@@ -115,7 +115,7 @@ class TestHostCPUStats(test.TestCase):
         # Make sure None is returned if there is no data.
         host_stats.cur_phyp = None
         host_stats._update_internal_metric()
-        self.assertEqual(None, host_stats.cur_data)
+        self.assertIsNone(host_stats.cur_data)
 
         # Make the 'prev' the current...for the first pass
         host_stats.cur_phyp = self.prev_phyp
diff --git a/nova_powervm/tests/virt/powervm/test_media.py b/nova_powervm/tests/virt/powervm/test_media.py
index 0ed1c144..1440ed26 100644
--- a/nova_powervm/tests/virt/powervm/test_media.py
+++ b/nova_powervm/tests/virt/powervm/test_media.py
@@ -222,7 +222,8 @@ class TestConfigDrivePowerVM(test.TestCase):
 
         self.apt.update_by_path.side_effect = validate_update
 
-        def validate_remove_stor(vg_w, vopts=[]):
+        def validate_remove_stor(vg_w, vopts=None):
+            vopts = {} if vopts is None else vopts
             self.assertIsInstance(vg_w, pvm_stor.VG)
             self.assertEqual(1, len(vopts))
             self.assertIsInstance(vopts[0], pvm_stor.VOptMedia)
@@ -253,7 +254,8 @@ class TestConfigDrivePowerVM(test.TestCase):
         self.apt.read.side_effect = [self.vio_to_vg, self.vg_to_vio]
         mock_vm_id.return_value = '2'
 
-        def validate_remove_stor(vg_w, vopts=[]):
+        def validate_remove_stor(vg_w, vopts=None):
+            vopts = {} if vopts is None else vopts
             self.assertIsInstance(vg_w, pvm_stor.VG)
             self.assertEqual(1, len(vopts))
             self.assertIsInstance(vopts[0], pvm_stor.VOptMedia)
diff --git a/nova_powervm/virt/powervm/tasks/storage.py b/nova_powervm/virt/powervm/tasks/storage.py
index e5f8a3fe..28d3aa84 100644
--- a/nova_powervm/virt/powervm/tasks/storage.py
+++ b/nova_powervm/virt/powervm/tasks/storage.py
@@ -534,10 +534,11 @@ class FindDisk(task.Task):
         LOG.info(_LI('Finding disk for instance: %s'), self.instance.name)
         disk = self.disk_dvr.get_disk_ref(self.instance, self.disk_type)
         if not disk:
-            LOG.warn(_LW('Disk not found: %(disk_name)s'),
-                     {'disk_name': self.disk_dvr._get_disk_name(self.disk_type,
-                                                                self.instance)
-                      }, instance=self.instance)
+            LOG.warning(_LW('Disk not found: %(disk_name)s'),
+                        {'disk_name':
+                            self.disk_dvr._get_disk_name(self.disk_type,
+                                                         self.instance),
+                         }, instance=self.instance)
         return disk
 
 
diff --git a/nova_powervm/virt/powervm/vm.py b/nova_powervm/virt/powervm/vm.py
index f56538ba..8d6b7e91 100644
--- a/nova_powervm/virt/powervm/vm.py
+++ b/nova_powervm/virt/powervm/vm.py
@@ -14,8 +14,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import json
 from oslo_log import log as logging
+from oslo_serialization import jsonutils
 import re
 import six
 
@@ -470,7 +470,7 @@ def get_vm_qp(adapter, lpar_uuid, qprop=None, log_errors=True):
             LOG.exception(e)
             raise
 
-    return json.loads(resp.body)
+    return jsonutils.loads(resp.body)
 
 
 def crt_lpar(adapter, host_wrapper, instance, flavor):
diff --git a/tox.ini b/tox.ini
index 6a9189e9..6ee93c9b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -34,3 +34,6 @@ whitelist_externals = bash
 [flake8]
 ignore = E125,H405
 exclude =  .venv,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*egg,build,tools
+
+[hacking]
+local-check-factory = nova_powervm.hacking.checks.factory
\ No newline at end of file