net/mlx5: Update log_max_qp value to be 17 at most

commit 7f83996 upstream.

Currently, log_max_qp value is dependent on what FW reports as its max capability.
In reality, due to a bug, some FWs report a value greater than 17, even though they
don't support log_max_qp > 17.

This FW issue led the driver to exhaust memory on startup.
Thus, log_max_qp value is set to be no more than 17 regardless
of what FW reports, as it was before the cited commit.

Fixes: f79a609 ("net/mlx5: Update log_max_qp value to FW max capability")
Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/ethernet/mellanox/mlx5/core/main.c

@@ -516,7 +516,7 @@ static int handle_hca_cap(struct mlx5_core_dev *dev, void *set_ctx)
 
 	/* Check log_max_qp from HCA caps to set in current profile */
 	if (prof->log_max_qp == LOG_MAX_SUPPORTED_QPS) {
-		prof->log_max_qp = MLX5_CAP_GEN_MAX(dev, log_max_qp);
+		prof->log_max_qp = min_t(u8, 17, MLX5_CAP_GEN_MAX(dev, log_max_qp));
 	} else if (MLX5_CAP_GEN_MAX(dev, log_max_qp) < prof->log_max_qp) {
 		mlx5_core_warn(dev, "log_max_qp value in current profile is %d, changing it to HCA capability limit (%d)\n",
 			       prof->log_max_qp,