--- zzzz-none-000/linux-3.10.107/drivers/infiniband/ulp/ipoib/ipoib_vlan.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/infiniband/ulp/ipoib/ipoib_vlan.c	2021-02-04 17:41:59.000000000 +0000
@@ -58,6 +58,7 @@
 	/* MTU will be reset when mcast join happens */
 	priv->dev->mtu   = IPOIB_UD_MTU(priv->max_ib_mtu);
 	priv->mcast_mtu  = priv->admin_mtu = priv->dev->mtu;
+	priv->parent = ppriv->dev;
 	set_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags);
 
 	result = ipoib_set_dev_features(priv, ppriv->ca);
@@ -84,8 +85,6 @@
 		goto register_failed;
 	}
 
-	priv->parent = ppriv->dev;
-
 	ipoib_create_debug_files(priv->dev);
 
 	/* RTNL childs don't need proprietary sysfs entries */
@@ -102,7 +101,6 @@
 	}
 
 	priv->child_type  = type;
-	priv->dev->iflink = ppriv->dev->ifindex;
 	list_add_tail(&priv->list, &ppriv->child_intfs);
 
 	return 0;
@@ -140,7 +138,7 @@
 	if (!rtnl_trylock())
 		return restart_syscall();
 
-	mutex_lock(&ppriv->vlan_mutex);
+	down_write(&ppriv->vlan_rwsem);
 
 	/*
 	 * First ensure this isn't a duplicate. We check the parent device and
@@ -163,7 +161,7 @@
 	result = __ipoib_vlan_add(ppriv, priv, pkey, IPOIB_LEGACY_CHILD);
 
 out:
-	mutex_unlock(&ppriv->vlan_mutex);
+	up_write(&ppriv->vlan_rwsem);
 
 	if (result)
 		free_netdev(priv->dev);
@@ -185,7 +183,8 @@
 
 	if (!rtnl_trylock())
 		return restart_syscall();
-	mutex_lock(&ppriv->vlan_mutex);
+
+	down_write(&ppriv->vlan_rwsem);
 	list_for_each_entry_safe(priv, tpriv, &ppriv->child_intfs, list) {
 		if (priv->pkey == pkey &&
 		    priv->child_type == IPOIB_LEGACY_CHILD) {
@@ -195,7 +194,8 @@
 			break;
 		}
 	}
-	mutex_unlock(&ppriv->vlan_mutex);
+	up_write(&ppriv->vlan_rwsem);
+
 	rtnl_unlock();
 
 	if (dev) {