diff --git a/nova/network/neutronv2/api.py b/nova/network/neutronv2/api.py
index 54f0e57791..549c73e502 100644
--- a/nova/network/neutronv2/api.py
+++ b/nova/network/neutronv2/api.py
@@ -3369,8 +3369,14 @@ class API(base_api.NetworkAPI):
                     # mapping based on that.
                     raise exception.PortUpdateFailed(
                         port_id=p['id'],
-                        reason=_("Provider mappings wasn't provided for the "
-                                 "port with resource request"))
+                        reason=_(
+                            "Provider mappings are not available to the "
+                            "compute service but are required for ports with "
+                            "a resource request. If compute RPC API versions "
+                            "are pinned for a rolling upgrade, you will need "
+                            "to retry this operation once the RPC version is "
+                            "unpinned and the nova-compute services are all "
+                            "upgraded."))
 
                 # NOTE(gibi): In the resource provider mapping there can be
                 # more than one RP fulfilling a request group. But resource
diff --git a/nova/tests/unit/network/test_neutronv2.py b/nova/tests/unit/network/test_neutronv2.py
index 6c431bad22..118ca2655f 100644
--- a/nova/tests/unit/network/test_neutronv2.py
+++ b/nova/tests/unit/network/test_neutronv2.py
@@ -4543,8 +4543,8 @@ class TestNeutronv2WithMock(TestNeutronv2Base):
              constants.BINDING_PROFILE:
                  {'allocation': uuids.source_compute_rp},
              'resource_request': mock.sentinel.resource_request}]}
-        migration = {'status': 'confirmed',
-                     'migration_type': "migration"}
+        migration = objects.Migration(
+            status='confirmed', migration_type='migration')
         list_ports_mock = mock.Mock(return_value=fake_ports)
         get_client_mock.return_value.list_ports = list_ports_mock
 
@@ -4569,8 +4569,8 @@ class TestNeutronv2WithMock(TestNeutronv2Base):
              constants.BINDING_PROFILE:
                  {'allocation': uuids.source_compute_rp},
              'resource_request': mock.sentinel.resource_request}]}
-        migration = {'status': 'confirmed',
-                     'migration_type': "migration"}
+        migration = objects.Migration(
+            status='confirmed', migration_type='migration')
         list_ports_mock = mock.Mock(return_value=fake_ports)
         get_client_mock.return_value.list_ports = list_ports_mock
 
@@ -4579,8 +4579,11 @@ class TestNeutronv2WithMock(TestNeutronv2Base):
             self.api._update_port_binding_for_instance, self.context,
             instance, 'new-host', migration, provider_mappings=None)
         self.assertIn(
-            "Provider mappings wasn't provided for the port with resource "
-            "request", six.text_type(ex))
+            "Provider mappings are not available to the compute service but "
+            "are required for ports with a resource request. If compute RPC "
+            "API versions are pinned for a rolling upgrade, you will need to "
+            "retry this operation once the RPC version is unpinned and the "
+            "nova-compute services are all upgraded.", six.text_type(ex))
 
     def test_get_pci_mapping_for_migration(self):
         instance = fake_instance.fake_instance_obj(self.context)