--- zzzz-none-000/linux-2.6.32.61/drivers/infiniband/ulp/ipoib/ipoib_multicast.c	2013-06-10 09:43:48.000000000 +0000
+++ ar9-7330-650/linux-2.6.32.61/drivers/infiniband/ulp/ipoib/ipoib_multicast.c	2010-04-08 11:00:21.000000000 +0000
@@ -188,9 +188,7 @@
 
 	mcast->mcmember = *mcmember;
 
-	/* Set the multicast MTU and cached Q_Key before we attach if it's
-	 * the broadcast group.
-	 */
+	/* Set the cached Q_Key before we attach if it's the broadcast group */
 	if (!memcmp(mcast->mcmember.mgid.raw, priv->dev->broadcast + 4,
 		    sizeof (union ib_gid))) {
 		spin_lock_irq(&priv->lock);
@@ -198,17 +196,10 @@
 			spin_unlock_irq(&priv->lock);
 			return -EAGAIN;
 		}
-		priv->mcast_mtu = IPOIB_UD_MTU(ib_mtu_enum_to_int(priv->broadcast->mcmember.mtu));
 		priv->qkey = be32_to_cpu(priv->broadcast->mcmember.qkey);
 		spin_unlock_irq(&priv->lock);
 		priv->tx_wr.wr.ud.remote_qkey = priv->qkey;
 		set_qkey = 1;
-
-		if (!ipoib_cm_admin_enabled(dev)) {
-			rtnl_lock();
-			dev_set_mtu(dev, min(priv->mcast_mtu, priv->admin_mtu));
-			rtnl_unlock();
-		}
 	}
 
 	if (!test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
@@ -597,6 +588,14 @@
 		return;
 	}
 
+	priv->mcast_mtu = IPOIB_UD_MTU(ib_mtu_enum_to_int(priv->broadcast->mcmember.mtu));
+
+	if (!ipoib_cm_admin_enabled(dev)) {
+		rtnl_lock();
+		dev_set_mtu(dev, min(priv->mcast_mtu, priv->admin_mtu));
+		rtnl_unlock();
+	}
+
 	ipoib_dbg_mcast(priv, "successfully joined all multicast groups\n");
 
 	clear_bit(IPOIB_MCAST_RUN, &priv->flags);