Re: [PATCH net-next 7/7] net/mlx5e: Use extack in set rxfh callback

[Simon Horman <horms@kernel.org>]

On Mon, Sep 22, 2025 at 12:01:11PM +0300, Tariq Toukan wrote:
> From: Gal Pressman <gal@nvidia.com>
> 
> The ->set_rxfh() callback now passes a valid extack instead of NULL
> through netlink [1]. In case of an error, reflect it through extack instead
> of a dmesg print.
> 
> [1]
> commit c0ae03588bbb ("ethtool: rss: initial RSS_SET (indirection table handling)")
> 
> Signed-off-by: Gal Pressman <gal@nvidia.com>
> Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
> ---
>  .../net/ethernet/mellanox/mlx5/core/en_ethtool.c  | 15 +++++++++------
>  1 file changed, 9 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
> index d507366d773e..eb25b19b4a4a 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
> @@ -1494,7 +1494,8 @@ static int mlx5e_get_rxfh(struct net_device *netdev, struct ethtool_rxfh_param *
>  }
>  
>  static int mlx5e_rxfh_hfunc_check(struct mlx5e_priv *priv,
> -				  const struct ethtool_rxfh_param *rxfh)
> +				  const struct ethtool_rxfh_param *rxfh,
> +				  struct netlink_ext_ack *extack)
>  {
>  	unsigned int count;
>  
> @@ -1504,8 +1505,10 @@ static int mlx5e_rxfh_hfunc_check(struct mlx5e_priv *priv,
>  		unsigned int xor8_max_channels = mlx5e_rqt_max_num_channels_allowed_for_xor8();
>  
>  		if (count > xor8_max_channels) {
> -			netdev_err(priv->netdev, "%s: Cannot set RSS hash function to XOR, current number of channels (%d) exceeds the maximum allowed for XOR8 RSS hfunc (%d)\n",
> -				   __func__, count, xor8_max_channels);
> +			NL_SET_ERR_MSG_FMT_MOD(
> +				extack,
> +				"Cannot set RSS hash function to XOR, current number of channels (%d) exceeds the maximum allowed for XOR8 RSS hfunc (%d)\n",
> +				count, xor8_max_channels);
>  			return -EINVAL;
>  		}
>  	}

Hi Tariq and Gal,

Coccinelle says: "WARNING avoid newline at end of message in NL_SET_ERR_MSG_FMT_MOD"

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