[openib-general] [PATCH] IB/ipoib: compliance/interoperability fix

[Michael S. Tsirkin]

ipoib assumes that high (reserved) octet in hardware address is 0, and copies
it into the QPN.  This violates RFC 4391 (which requires that the high 8 bits
are ignored on receive), and will result in invalid QPN passed to hardware when
inter-operating with IPoIB connected mode.

Signed-off-by: Michael S. Tsirkin <mst at mellanox.co.il>

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 1eaf00e..cdc98b1 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -49,6 +49,8 @@ #include <linux/in.h>
 
 #include <net/dst.h>
 
+#define IPOIB_QPN(ha) (be32_to_cpup((__be32 *) ha) & 0xffffff)
+
 MODULE_AUTHOR("Roland Dreier");
 MODULE_DESCRIPTION("IP-over-InfiniBand net driver");
 MODULE_LICENSE("Dual BSD/GPL");
@@ -517,6 +516,5 @@ static void neigh_add_path(struct sk_buf
 
-		ipoib_send(dev, skb, path->ah,
-			   be32_to_cpup((__be32 *) skb->dst->neighbour->ha));
+		ipoib_send(dev, skb, path->ah, IPOIB_QPN(skb->dst->neighbour->ha));
 	} else {
 		neigh->ah  = NULL;
 		__skb_queue_tail(&neigh->queue, skb);
@@ -599,8 +594,7 @@ static void unicast_arp_send(struct sk_b
 		ipoib_dbg(priv, "Send unicast ARP to %04x\n",
 			  be16_to_cpu(path->pathrec.dlid));
 
-		ipoib_send(dev, skb, path->ah,
-			   be32_to_cpup((__be32 *) phdr->hwaddr));
+		ipoib_send(dev, skb, path->ah, IPOIB_QPN(phdr->hwaddr));
 	} else if ((path->query || !path_rec_start(dev, path)) &&
 		   skb_queue_len(&path->queue) < IPOIB_MAX_PATH_REC_QUEUE) {
 		/* put pseudoheader back on for next time */
@@ -661,8 +655,7 @@ static int ipoib_start_xmit(struct sk_bu
 				goto out;
 			}
 
-			ipoib_send(dev, skb, neigh->ah,
-				   be32_to_cpup((__be32 *) skb->dst->neighbour->ha));
+			ipoib_send(dev, skb, neigh->ah, IPOIB_QPN(skb->dst->neighbour->ha));
 			goto out;
 		}
 
@@ -694,7 +687,7 @@ static int ipoib_start_xmit(struct sk_bu
 					   IPOIB_GID_FMT "\n",
 					   skb->dst ? "neigh" : "dst",
 					   be16_to_cpup((__be16 *) skb->data),
-					   be32_to_cpup((__be32 *) phdr->hwaddr),
+					   IPOIB_QPN(phdr->hwaddr),
 					   IPOIB_GID_RAW_ARG(phdr->hwaddr + 4));
 				dev_kfree_skb_any(skb);
 				++priv->stats.tx_dropped;
@@ -777,7 +770,7 @@ static void ipoib_neigh_destructor(struc
 
 	ipoib_dbg(priv,
 		  "neigh_destructor for %06x " IPOIB_GID_FMT "\n",
-		  be32_to_cpup((__be32 *) n->ha),
+		  IPOIB_QPN(n->ha),
 		  IPOIB_GID_RAW_ARG(n->ha + 4));
 
 	spin_lock_irqsave(&priv->lock, flags);

-- 
MST