[PATCH 4.9 017/101] IB/mlx5: Avoid load failure due to unknown link width

From: Greg Kroah-Hartman
Date: Thu Dec 06 2018 - 09:54:57 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Michael Guralnik <michaelgur@xxxxxxxxxxxx>

commit db7a691a1551a748cb92d9c89c6b190ea87e28d5 upstream.

If the firmware reports a connection width that is not 1x, 4x, 8x or 12x
it causes the driver to fail during initialization.

To prevent this failure every time a new width is introduced to the RDMA
stack, we will set a default 4x width for these widths which ar unknown to
the driver.

This is needed to allow to run old kernels with new firmware.

Cc: <stable@xxxxxxxxxxxxxxx> # 4.1
Fixes: 1b5daf11b015 ("IB/mlx5: Avoid using the MAD_IFC command under ISSI > 0 mode")
Signed-off-by: Michael Guralnik <michaelgur@xxxxxxxxxxxx>
Reviewed-by: Majd Dibbiny <majd@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/infiniband/hw/mlx5/main.c | 29 +++++++++++------------------
1 file changed, 11 insertions(+), 18 deletions(-)

--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -710,31 +710,26 @@ enum mlx5_ib_width {
MLX5_IB_WIDTH_12X = 1 << 4
};

-static int translate_active_width(struct ib_device *ibdev, u8 active_width,
+static void translate_active_width(struct ib_device *ibdev, u8 active_width,
u8 *ib_width)
{
struct mlx5_ib_dev *dev = to_mdev(ibdev);
- int err = 0;

- if (active_width & MLX5_IB_WIDTH_1X) {
+ if (active_width & MLX5_IB_WIDTH_1X)
*ib_width = IB_WIDTH_1X;
- } else if (active_width & MLX5_IB_WIDTH_2X) {
- mlx5_ib_dbg(dev, "active_width %d is not supported by IB spec\n",
- (int)active_width);
- err = -EINVAL;
- } else if (active_width & MLX5_IB_WIDTH_4X) {
+ else if (active_width & MLX5_IB_WIDTH_4X)
*ib_width = IB_WIDTH_4X;
- } else if (active_width & MLX5_IB_WIDTH_8X) {
+ else if (active_width & MLX5_IB_WIDTH_8X)
*ib_width = IB_WIDTH_8X;
- } else if (active_width & MLX5_IB_WIDTH_12X) {
+ else if (active_width & MLX5_IB_WIDTH_12X)
*ib_width = IB_WIDTH_12X;
- } else {
- mlx5_ib_dbg(dev, "Invalid active_width %d\n",
+ else {
+ mlx5_ib_dbg(dev, "Invalid active_width %d, setting width to default value: 4x\n",
(int)active_width);
- err = -EINVAL;
+ *ib_width = IB_WIDTH_4X;
}

- return err;
+ return;
}

static int mlx5_mtu_to_ib_mtu(int mtu)
@@ -842,10 +837,8 @@ static int mlx5_query_hca_port(struct ib
if (err)
goto out;

- err = translate_active_width(ibdev, ib_link_width_oper,
- &props->active_width);
- if (err)
- goto out;
+ translate_active_width(ibdev, ib_link_width_oper, &props->active_width);
+
err = mlx5_query_port_ib_proto_oper(mdev, &props->active_speed, port);
if (err)
goto out;