Patch "IB/mlx4: Handle well-known-gid in mad_demux processing" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

IB/mlx4: Handle well-known-gid in mad_demux processing

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
ib-mlx4-handle-well-known-gid-in-mad_demux-processing.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jack Morgenstein <[email protected]>
Date: Thu, 10 Nov 2016 11:30:57 +0200
Subject: IB/mlx4: Handle well-known-gid in mad_demux processing

From: Jack Morgenstein <[email protected]>

commit befcabcd530e4ffb6f016638f693b7d94986d2ba upstream.

If OpenSM runs over a ConnectX-3, and there are ConnectX-4 or Connect-IB VFs active on the network, the OpenSM will receive QP1 packets containing a GRH where the destination GID is the "Well-Known GID" -- which is not a GID in the HCA Port's GID Table.

This GID must be tested-for separately -- and packets which contain this destination GID should be routed to slave 0 (the PF).

---
 drivers/infiniband/hw/mlx4/mad.c |   16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

@@ -702,10 +702,18 @@ static int mlx4_ib_demux_mad(struct ib_d
 
 	/* If a grh is present, we demux according to it */
 	if (wc->wc_flags & IB_WC_GRH) {
-		slave = mlx4_ib_find_real_gid(ibdev, port, grh->dgid.global.interface_id);
-		if (slave < 0) {
-			mlx4_ib_warn(ibdev, "failed matching grh\n");
-			return -ENOENT;
+		if (grh->dgid.global.interface_id ==
+			cpu_to_be64(IB_SA_WELL_KNOWN_GUID) &&
+		    grh->dgid.global.subnet_prefix == cpu_to_be64(
+			atomic64_read(&dev->sriov.demux[port - 1].subnet_prefix))) {
+			slave = 0;
+		} else {
+			slave = mlx4_ib_find_real_gid(ibdev, port,
+						      grh->dgid.global.interface_id);
+			if (slave < 0) {
+				mlx4_ib_warn(ibdev, "failed matching grh\n");
+				return -ENOENT;
+			}
 		}
 	}
 	/* Class-specific handling */

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/ib-mlx4-handle-well-known-gid-in-mad_demux-processing.patch queue-4.9/ib-mlx4-fix-out-of-range-array-index-in-destroy-qp-flow.patch