diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index 573270fcfb..22a235d40e 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -7759,6 +7759,25 @@ nm_device_set_unmanaged (NMDevice *self,
 	}
 }
 
+void
+nm_device_set_unmanaged_by_device_spec (NMDevice *self, const GSList *unmanaged_specs)
+{
+	NMDevicePrivate *priv;
+	gboolean unmanaged;
+
+	g_return_if_fail (NM_IS_DEVICE (self));
+
+	priv = NM_DEVICE_GET_PRIVATE (self);
+
+	unmanaged = nm_device_spec_match_list (self, unmanaged_specs);
+	nm_device_set_unmanaged (self,
+	                         NM_UNMANAGED_USER,
+	                         unmanaged,
+	                         unmanaged
+	                             ? NM_DEVICE_STATE_REASON_NOW_UNMANAGED
+	                             : NM_DEVICE_STATE_REASON_NOW_MANAGED);
+}
+
 void
 nm_device_set_unmanaged_quitting (NMDevice *self)
 {
diff --git a/src/devices/nm-device.h b/src/devices/nm-device.h
index 6d254d7330..00ea568e52 100644
--- a/src/devices/nm-device.h
+++ b/src/devices/nm-device.h
@@ -436,6 +436,7 @@ void nm_device_set_unmanaged (NMDevice *device,
                               NMUnmanagedFlags flag,
                               gboolean unmanaged,
                               NMDeviceStateReason reason);
+void nm_device_set_unmanaged_by_device_spec (NMDevice *self, const GSList *unmanaged_specs);
 void nm_device_set_unmanaged_quitting (NMDevice *device);
 void nm_device_set_initial_unmanaged_flag (NMDevice *device,
                                            NMUnmanagedFlags flag,
diff --git a/src/nm-manager.c b/src/nm-manager.c
index e72d705438..0e13f3b1e3 100644
--- a/src/nm-manager.c
+++ b/src/nm-manager.c
@@ -1084,17 +1084,8 @@ system_unmanaged_devices_changed_cb (NMSettings *settings,
 	const GSList *unmanaged_specs, *iter;
 
 	unmanaged_specs = nm_settings_get_unmanaged_specs (priv->settings);
-	for (iter = priv->devices; iter; iter = g_slist_next (iter)) {
-		NMDevice *device = NM_DEVICE (iter->data);
-		gboolean unmanaged;
-
-		unmanaged = nm_device_spec_match_list (device, unmanaged_specs);
-		nm_device_set_unmanaged (device,
-		                         NM_UNMANAGED_USER,
-		                         unmanaged,
-		                         unmanaged ? NM_DEVICE_STATE_REASON_NOW_UNMANAGED :
-		                                     NM_DEVICE_STATE_REASON_NOW_MANAGED);
-	}
+	for (iter = priv->devices; iter; iter = g_slist_next (iter))
+		nm_device_set_unmanaged_by_device_spec (NM_DEVICE (iter->data), unmanaged_specs);
 }
 
 static void