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

IB/mlx4: Fix incorrectly releasing steerable UD QPs when have only ETH ports

to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: ib-mlx4-fix-incorrectly-releasing-steerable-ud-qps-when-have-only-eth-ports.patch and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 852f6927594d0d3e8632c889b2ab38cbc46476ad Mon Sep 17 00:00:00 2001

From: Jack Morgenstein jackm@dev.mellanox.co.il Date: Fri, 12 Jan 2018 07:58:40 +0200 Subject: IB/mlx4: Fix incorrectly releasing steerable UD QPs when have only ETH ports

From: Jack Morgenstein jackm@dev.mellanox.co.il

commit 852f6927594d0d3e8632c889b2ab38cbc46476ad upstream.

Allocating steerable UD QPs depends on having at least one IB port, while releasing those QPs does not.

As a result, when there are only ETH ports, the IB (RoCE) driver requests releasing a qp range whose base qp is zero, with qp count zero.

When SR-IOV is enabled, and the VF driver is running on a VM over a hypervisor which treats such qp release calls as errors (rather than NOPs), we see lines in the VM message log like:

mlx4_core 0002:00:02.0: Failed to release qp range base:0 cnt:0

Fix this by adding a check for a zero count in mlx4_release_qp_range() (which thus treats releasing 0 qps as a nop), and eliminating the check for device managed flow steering when releasing steerable UD QPs. (Freeing ib_uc_qpns_bitmap unconditionally is also OK, since it remains NULL when steerable UD QPs are not allocated).

Fixes: 4196670be786 ("IB/mlx4: Don't allocate range of steerable UD QPs for Ethernet-only device") Signed-off-by: Jack Morgenstein jackm@dev.mellanox.co.il Signed-off-by: Leon Romanovsky leon@kernel.org Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/infiniband/hw/mlx4/main.c | 13 +++++-------- drivers/net/ethernet/mellanox/mlx4/qp.c | 3 +++ 2 files changed, 8 insertions(+), 8 deletions(-)

--- a/drivers/infiniband/hw/mlx4/main.c +++ b/drivers/infiniband/hw/mlx4/main.c @@ -2348,9 +2348,8 @@ err_steer_free_bitmap: kfree(ibdev->ib_uc_qpns_bitmap);

err_steer_qp_release: - if (ibdev->steering_support == MLX4_STEERING_MODE_DEVICE_MANAGED) - mlx4_qp_release_range(dev, ibdev->steer_qpn_base, - ibdev->steer_qpn_count); + mlx4_qp_release_range(dev, ibdev->steer_qpn_base, + ibdev->steer_qpn_count); err_counter: for (; i; --i) if (ibdev->counters[i - 1] != -1) @@ -2452,11 +2451,9 @@ static void mlx4_ib_remove(struct mlx4_d ibdev->iboe.nb.notifier_call = NULL; }

- if (ibdev->steering_support == MLX4_STEERING_MODE_DEVICE_MANAGED) { - mlx4_qp_release_range(dev, ibdev->steer_qpn_base, - ibdev->steer_qpn_count); - kfree(ibdev->ib_uc_qpns_bitmap); - } + mlx4_qp_release_range(dev, ibdev->steer_qpn_base, + ibdev->steer_qpn_count); + kfree(ibdev->ib_uc_qpns_bitmap);

if (ibdev->iboe.nb_inet.notifier_call) { if (unregister_inetaddr_notifier(&ibdev->iboe.nb_inet)) --- a/drivers/net/ethernet/mellanox/mlx4/qp.c +++ b/drivers/net/ethernet/mellanox/mlx4/qp.c @@ -257,6 +257,9 @@ void mlx4_qp_release_range(struct mlx4_d u64 in_param = 0; int err;

+ if (!cnt) + return; + if (mlx4_is_mfunc(dev)) { set_param_l(&in_param, base_qpn); set_param_h(&in_param, cnt);

Patches currently in stable-queue which might be from jackm@dev.mellanox.co.il are

queue-3.18/ib-mlx4-fix-incorrectly-releasing-steerable-ud-qps-when-have-only-eth-ports.patch