Re: [PATCH net 2/3] net/mlx5e: Validate bandwidth for non-ETS traffic classes

[Jakub Kicinski <kuba@kernel.org>]

On Mon, 22 Jun 2026 14:29:24 +0300 Tariq Toukan wrote:
> From: Alexei Lazar <alazar@nvidia.com>
> 
> The IEEE 802.1Qaz standard defines that bandwidth allocation percentages
> only apply to ETS traffic classes.
> 
> Reject ETS configurations that specify non-zero bandwidth for traffic
> classes.
> 
> Fixes: 08fb1dacdd76 ("net/mlx5e: Support DCBNL IEEE ETS")
> Signed-off-by: Alexei Lazar <alazar@nvidia.com>
> Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
> index 762f0a46c120..e4161603cdc0 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
> @@ -324,6 +324,17 @@ static int mlx5e_dbcnl_validate_ets(struct net_device *netdev,
>  		}
>  	}
>  
> +	/* Validate Non ETS BW */
> +	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
> +		if (ets->tc_tsa[i] != IEEE_8021QAZ_TSA_ETS &&
> +		    ets->tc_tx_bw[i]) {
> +			netdev_err(netdev,
> +				   "Failed to validate ETS: tc=%d BW is not 0 for non-ETS TC (tsa=%u, bw=%u)\n",
> +				   i, ets->tc_tsa[i], ets->tc_tx_bw[i]);
> +			return -EINVAL;
> +		}
> +	}

Can we pull this check out into the shared dcbnl handling?
There seems to be zero mlx5 specific logic in this patch,
and the motivation.

>  	/* Validate Bandwidth Sum */
>  	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
>  		if (ets->tc_tsa[i] == IEEE_8021QAZ_TSA_ETS) {