[PATCH] IB/ipoib: don't call ipoib_put_ah with lock held

ipoib_put_ah() may call ipoib_free_ah(), which might take the device's lock.
Therefore we need to make sure we don't call ipoib_put_ah() when holding the
lock already.
Signed-off-by: Shirley Ma <xma@us.ibm.com>
Signed-off-by: Roland Dreier <roland@topspin.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/infiniband/ulp/ipoib/ipoib_main.c

@@ -661,6 +661,7 @@ static void ipoib_neigh_destructor(struct neighbour *n)
 	struct ipoib_neigh *neigh = *to_ipoib_neigh(n);
 	struct ipoib_dev_priv *priv = netdev_priv(n->dev);
 	unsigned long flags;
+	struct ipoib_ah *ah = NULL;
 
 	ipoib_dbg(priv,
 		  "neigh_destructor for %06x " IPOIB_GID_FMT "\n",
@@ -671,13 +672,16 @@ static void ipoib_neigh_destructor(struct neighbour *n)
 
 	if (neigh) {
 		if (neigh->ah)
-			ipoib_put_ah(neigh->ah);
+			ah = neigh->ah;
 		list_del(&neigh->list);
 		*to_ipoib_neigh(n) = NULL;
 		kfree(neigh);
 	}
 
 	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (ah)
+		ipoib_put_ah(ah);
 }
 
 static int ipoib_neigh_setup(struct neighbour *neigh)

drivers/infiniband/ulp/ipoib/ipoib_multicast.c

@@ -93,6 +93,8 @@ static void ipoib_mcast_free(struct ipoib_mcast *mcast)
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_neigh *neigh, *tmp;
 	unsigned long flags;
+	LIST_HEAD(ah_list);
+	struct ipoib_ah *ah, *tah;
 
 	ipoib_dbg_mcast(netdev_priv(dev),
 			"deleting multicast group " IPOIB_GID_FMT "\n",
@@ -101,7 +103,8 @@ static void ipoib_mcast_free(struct ipoib_mcast *mcast)
 	spin_lock_irqsave(&priv->lock, flags);
 
 	list_for_each_entry_safe(neigh, tmp, &mcast->neigh_list, list) {
-		ipoib_put_ah(neigh->ah);
+		if (neigh->ah)
+			list_add_tail(&neigh->ah->list, &ah_list);
 		*to_ipoib_neigh(neigh->neighbour) = NULL;
 		neigh->neighbour->ops->destructor = NULL;
 		kfree(neigh);
@@ -109,6 +112,9 @@ static void ipoib_mcast_free(struct ipoib_mcast *mcast)
 
 	spin_unlock_irqrestore(&priv->lock, flags);
 
+	list_for_each_entry_safe(ah, tah, &ah_list, list)
+		ipoib_put_ah(ah);
+
 	if (mcast->ah)
 		ipoib_put_ah(mcast->ah);