3 files changed, 30 insertions, 11 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index 804cb4bee57d..1abe3c62f106 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -330,6 +330,13 @@ struct ipoib_dev_priv {
 
 	unsigned long flags;
 
+	/*
+	 * This protects access to the child_intfs list.
+	 * To READ from child_intfs the RTNL or vlan_rwsem read side must be
+	 * held.  To WRITE RTNL and the vlan_rwsem write side must be held (in
+	 * that order) This lock exists because we have a few contexts where
+	 * we need the child_intfs, but do not want to grab the RTNL.
+	 */
 	struct rw_semaphore vlan_rwsem;
 	struct mutex mcast_mutex;
 
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index e9f4f261fe20..b2fe23d60103 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -1939,18 +1939,15 @@ static int ipoib_ndo_init(struct net_device *ndev)
 
 static void ipoib_ndo_uninit(struct net_device *dev)
 {
-	struct ipoib_dev_priv *priv = ipoib_priv(dev), *cpriv, *tcpriv;
-	LIST_HEAD(head);
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
 
 	ASSERT_RTNL();
 
-	/* Delete any child interfaces first */
-	list_for_each_entry_safe(cpriv, tcpriv, &priv->child_intfs, list) {
-		/* Stop GC on child */
-		cancel_delayed_work_sync(&cpriv->neigh_reap_task);
-		unregister_netdevice_queue(cpriv->dev, &head);
-	}
-	unregister_netdevice_many(&head);
+	/*
+	 * ipoib_remove_one guarantees the children are removed before the
+	 * parent, and that is the only place where a parent can be removed.
+	 */
+	WARN_ON(!list_empty(&priv->child_intfs));
 
 	ipoib_neigh_hash_uninit(dev);
 
@@ -2466,16 +2463,25 @@ static void ipoib_add_one(struct ib_device *device)
 
 static void ipoib_remove_one(struct ib_device *device, void *client_data)
 {
-	struct ipoib_dev_priv *priv, *tmp;
+	struct ipoib_dev_priv *priv, *tmp, *cpriv, *tcpriv;
 	struct list_head *dev_list = client_data;
 
 	if (!dev_list)
 		return;
 
 	list_for_each_entry_safe(priv, tmp, dev_list, list) {
+		LIST_HEAD(head);
 		ipoib_parent_unregister_pre(priv->dev);
 
-		unregister_netdev(priv->dev);
+		rtnl_lock();
+
+		list_for_each_entry_safe(cpriv, tcpriv, &priv->child_intfs,
+					 list)
+			unregister_netdevice_queue(cpriv->dev, &head);
+		unregister_netdevice_queue(priv->dev, &head);
+		unregister_netdevice_many(&head);
+
+		rtnl_unlock();
 	}
 
 	kfree(dev_list);
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_vlan.c b/drivers/infiniband/ulp/ipoib/ipoib_vlan.c
index 891c5b40018a..fa4dfcee2644 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_vlan.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_vlan.c
@@ -67,6 +67,12 @@ int __ipoib_vlan_add(struct ipoib_dev_priv *ppriv, struct ipoib_dev_priv *priv,
 
 	ASSERT_RTNL();
 
+	/*
+	 * Racing with unregister of the parent must be prevented by the
+	 * caller.
+	 */
+	WARN_ON(ppriv->dev->reg_state != NETREG_REGISTERED);
+
 	priv->parent = ppriv->dev;
 	priv->pkey = pkey;
 	priv->child_type = type;