3 files changed, 28 insertions, 4 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index 3f89f5e1903..474aa214ab5 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -212,6 +212,7 @@ struct ipoib_path {
 
 struct ipoib_neigh {
 	struct ipoib_ah    *ah;
+	union ib_gid        dgid;
 	struct sk_buff_head queue;
 
 	struct neighbour   *neighbour;
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 1c6ea1c682a..cf71d2a5515 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -404,6 +404,8 @@ static void path_rec_completion(int status,
 		list_for_each_entry(neigh, &path->neigh_list, list) {
 			kref_get(&path->ah->ref);
 			neigh->ah = path->ah;
+			memcpy(&neigh->dgid.raw, &path->pathrec.dgid.raw,
+			       sizeof(union ib_gid));
 
 			while ((skb = __skb_dequeue(&neigh->queue)))
 				__skb_queue_tail(&skqueue, skb);
@@ -510,6 +512,8 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 	if (path->ah) {
 		kref_get(&path->ah->ref);
 		neigh->ah = path->ah;
+		memcpy(&neigh->dgid.raw, &path->pathrec.dgid.raw,
+		       sizeof(union ib_gid));
 
 		ipoib_send(dev, skb, path->ah,
 			   be32_to_cpup((__be32 *) skb->dst->neighbour->ha));
@@ -633,6 +637,25 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		neigh = *to_ipoib_neigh(skb->dst->neighbour);
 
 		if (likely(neigh->ah)) {
+			if (unlikely(memcmp(&neigh->dgid.raw,
+					    skb->dst->neighbour->ha + 4,
+					    sizeof(union ib_gid)))) {
+				spin_lock(&priv->lock);
+				/*
+				 * It's safe to call ipoib_put_ah() inside
+				 * priv->lock here, because we know that
+				 * path->ah will always hold one more reference,
+				 * so ipoib_put_ah() will never do more than
+				 * decrement the ref count.
+				 */
+				ipoib_put_ah(neigh->ah);
+				list_del(&neigh->list);
+				ipoib_neigh_free(neigh);
+				spin_unlock(&priv->lock);
+				ipoib_path_lookup(skb, dev);
+				goto out;
+			}
+
 			ipoib_send(dev, skb, neigh->ah,
 				   be32_to_cpup((__be32 *) skb->dst->neighbour->ha));
 			goto out;
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
index ab40488182b..b5e6a7be603 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
@@ -264,6 +264,10 @@ static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast,
 		if (!ah) {
 			ipoib_warn(priv, "ib_address_create failed\n");
 		} else {
+			spin_lock_irq(&priv->lock);
+			mcast->ah = ah;
+			spin_unlock_irq(&priv->lock);
+
 			ipoib_dbg_mcast(priv, "MGID " IPOIB_GID_FMT
 					" AV %p, LID 0x%04x, SL %d\n",
 					IPOIB_GID_ARG(mcast->mcmember.mgid),
@@ -271,10 +275,6 @@ static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast,
 					be16_to_cpu(mcast->mcmember.mlid),
 					mcast->mcmember.sl);
 		}
-
-		spin_lock_irq(&priv->lock);
-		mcast->ah = ah;
-		spin_unlock_irq(&priv->lock);
 	}
 
 	/* actually send any queued packets */