+static int mvsw_pr_port_obj_attr_set(struct net_device *dev,
+				     const struct switchdev_attr *attr,
+				     struct switchdev_trans *trans)
+{
+	int err = 0;
+	struct mvsw_pr_port *port = netdev_priv(dev);
+
+	switch (attr->id) {
+	case SWITCHDEV_ATTR_ID_PORT_STP_STATE:
+		err = -EOPNOTSUPP;
+		break;

That is interesting. Is the linux bridge happy with this? Particularly
when you have other interfaces in the Linux SW bridge, which cause a
loop via the switch ports? I assume the network then dies in a
broadcast storm, since there is nothing Linux can do to solve the
loop.

       Andrew