[ofa-general] [PATCH] ib/ipoib: handle Gratuitous ARP & bonding failover race also for connected mode neighbours

[Or Gerlitz]

move a little up the code that checks for a situation where the remote GID stored in the ipoib_neigh is
different than the one present in the neighbour (handle Gratuitous ARP) or that a bonding fail over has
happened but the neighbour still has a pointer to an ipoib_neigh created not by the current slave. This
will cause the driver to apply the check also for connected mode neighbours.

Signed-off-by: Or Gerlitz <ogerlitz at voltaire.com>

I have tested this patch on 2.6.24-rc1 (and its now in progress for 2.6.24-rc8)
things are basically working fine, but I do want to play more with bonding fail-overs
to make sure nothing was broken wrt to Gratuitous ARP etc, will let you know.

-----

Index: linux-2.6.24-rc8/drivers/infiniband/ulp/ipoib/ipoib_main.c
===================================================================
--- linux-2.6.24-rc8.orig/drivers/infiniband/ulp/ipoib/ipoib_main.c	2008-01-17 16:37:10.000000000 +0200
+++ linux-2.6.24-rc8/drivers/infiniband/ulp/ipoib/ipoib_main.c	2008-01-17 16:46:51.000000000 +0200
@@ -686,13 +686,8 @@ static int ipoib_start_xmit(struct sk_bu
 		}

 		neigh = *to_ipoib_neigh(skb->dst->neighbour);
-
-		if (ipoib_cm_get(neigh)) {
-			if (ipoib_cm_up(neigh)) {
-				ipoib_cm_send(dev, skb, ipoib_cm_get(neigh));
-				goto out;
-			}
-		} else if (neigh->ah) {
+
+		if (neigh->ah)
 			if (unlikely((memcmp(&neigh->dgid.raw,
 					    skb->dst->neighbour->ha + 4,
 					    sizeof(union ib_gid))) ||
@@ -713,6 +708,12 @@ static int ipoib_start_xmit(struct sk_bu
 				goto out;
 			}

+		if (ipoib_cm_get(neigh)) {
+			if (ipoib_cm_up(neigh)) {
+				ipoib_cm_send(dev, skb, ipoib_cm_get(neigh));
+				goto out;
+			}
+		} else if (neigh->ah) {
 			ipoib_send(dev, skb, neigh->ah, IPOIB_QPN(skb->dst->neighbour->ha));
 			goto out;
 		}