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>>> ft_attr.prio = 0; >>> ns = mlx5_get_flow_namespace(priv->mdev, MLX5_FLOW_NAMESPACE_KERNEL); >>> + if (!ns) { >>> + netdev_err(priv->mdev, "Failed to get flow namespace\n"); >>> + return -EOPNOTSUPP; >>> + } >>> *ft = mlx5_create_auto_grouped_flow_table(ns, &ft_attr); >>> if (IS_ERR(*ft)) { >> >> Same question here, did it fail for you, or just saw it while reading the >> code? > I just saw it while reading the code. > I've been working on code vulnerability scanning recently. > I don't believe this scenario can actually occur. The function mlx5e_tc_nic_init() is called from mlx5e_init_nic_rx(), and before that, we invoke mlx5e_create_flow_steering(). In mlx5e_create_flow_steering(), the first operation is: int mlx5e_create_flow_steering(struct mlx5e_flow_steering *fs, struct mlx5e_rx_res *rx_res, const struct mlx5e_profile *profile, struct net_device *netdev) { struct mlx5_flow_namespace *ns = mlx5_get_flow_namespace(fs->mdev, MLX5_FLOW_NAMESPACE_KERNEL); int err; if (!ns) return -EOPNOTSUPP; Note that MLX5_FLOW_NAMESPACE_KERNEL is allocated and initialized at driver startup (as most/all namespaces), and it does not change dynamically. If mlx5e_create_flow_steering() fails, it indicates that something fundamental isn't functioning correctly, and we never proceed to the more advanced functionality (like tc). Mark