Patch "IB/mlx4: When no DMFS for IPoIB, don't allow NET_IF QPs" has been added to the 4.4-stable tree

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

IB/mlx4: When no DMFS for IPoIB, don't allow NET_IF QPs

to the 4.4-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-when-no-dmfs-for-ipoib-don-t-allow-net_if-qps.patch
and it can be found in the queue-4.4 subdirectory.

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

From: Eran Ben Elisha <[email protected]>
Date: Thu, 10 Nov 2016 11:31:00 +0200
Subject: IB/mlx4: When no DMFS for IPoIB, don't allow NET_IF QPs

From: Eran Ben Elisha <[email protected]>

commit 1f22e454df2eb99ba6b7ace3f594f6805cdf5cbc upstream.

According to the firmware spec, FLOW_STEERING_IB_UC_QP_RANGE command is supported only if dmfs_ipoib bit is set.

If it isn't set we want to ensure allocating NET_IF QPs fail. We do so by filling out the allocation bitmap. By thus, the NET_IF QPs allocating function won't find any free QP and will fail.

---
 drivers/infiniband/hw/mlx4/main.c |   21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

@@ -2403,14 +2403,19 @@ static void *mlx4_ib_add(struct mlx4_dev
 			goto err_steer_qp_release;
 		}
 
-		bitmap_zero(ibdev->ib_uc_qpns_bitmap, ibdev->steer_qpn_count);
-
-		err = mlx4_FLOW_STEERING_IB_UC_QP_RANGE(
-				dev, ibdev->steer_qpn_base,
-				ibdev->steer_qpn_base +
-				ibdev->steer_qpn_count - 1);
-		if (err)
-			goto err_steer_free_bitmap;
+		if (dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_DMFS_IPOIB) {
+			bitmap_zero(ibdev->ib_uc_qpns_bitmap,
+				    ibdev->steer_qpn_count);
+			err = mlx4_FLOW_STEERING_IB_UC_QP_RANGE(
+					dev, ibdev->steer_qpn_base,
+					ibdev->steer_qpn_base +
+					ibdev->steer_qpn_count - 1);
+			if (err)
+				goto err_steer_free_bitmap;
+		} else {
+			bitmap_fill(ibdev->ib_uc_qpns_bitmap,
+				    ibdev->steer_qpn_count);
+		}
 	}
 
 	for (j = 1; j <= ibdev->dev->caps.num_ports; j++)

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

queue-4.4/ib-mlx4-when-no-dmfs-for-ipoib-don-t-allow-net_if-qps.patch