Re: [PATCH net-next] net/mlx5: fix uninit value use

[Michal Swiatkowski]

On Wed, Oct 25, 2023 at 04:50:50PM +0200, Przemek Kitszel wrote:
> Avoid use of uninitialized state variable.
> 
> In case of mlx5e_tx_reporter_build_diagnose_output_sq_common() it's better
> to still collect other data than bail out entirely.
> 
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> Link: https://lore.kernel.org/netdev/8bd30131-c9f2-4075-a575-7fa2793a1760@moroto.mountain
> Fixes: d17f98bf7cc9 ("net/mlx5: devlink health: use retained error fmsg API")
> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@xxxxxxxxx>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/en/reporter_rx.c | 6 +++++-
>  drivers/net/ethernet/mellanox/mlx5/core/en/reporter_tx.c | 8 ++++++--
>  2 files changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_rx.c
> index fc5a9fdd06db..fea8c0a5fe89 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_rx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_rx.c
> @@ -263,8 +263,12 @@ mlx5e_rx_reporter_build_diagnose_output_rq_common(struct mlx5e_rq *rq,
>  	if (rq->icosq) {
>  		struct mlx5e_icosq *icosq = rq->icosq;
>  		u8 icosq_hw_state;
> +		int err;
> +
> +		err = mlx5_core_query_sq_state(rq->mdev, icosq->sqn, &icosq_hw_state);
> +		if (err)
> +			return err;
>  
> -		mlx5_core_query_sq_state(rq->mdev, icosq->sqn, &icosq_hw_state);
>  		mlx5e_reporter_icosq_diagnose(icosq, icosq_hw_state, fmsg);
>  	}
>  
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_tx.c
> index ccff7c26d6ac..6b44ddce14e9 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_tx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/reporter_tx.c
> @@ -221,12 +221,16 @@ mlx5e_tx_reporter_build_diagnose_output_sq_common(struct devlink_fmsg *fmsg,
>  	bool stopped = netif_xmit_stopped(sq->txq);
>  	struct mlx5e_priv *priv = sq->priv;
>  	u8 state;
> +	int err;
>  
> -	mlx5_core_query_sq_state(priv->mdev, sq->sqn, &state);
>  	devlink_fmsg_u32_pair_put(fmsg, "tc", tc);
>  	devlink_fmsg_u32_pair_put(fmsg, "txq ix", sq->txq_ix);
>  	devlink_fmsg_u32_pair_put(fmsg, "sqn", sq->sqn);
> -	devlink_fmsg_u8_pair_put(fmsg, "HW state", state);
> +
> +	err = mlx5_core_query_sq_state(priv->mdev, sq->sqn, &state);
> +	if (!err)
> +		devlink_fmsg_u8_pair_put(fmsg, "HW state", state);
> +
>  	devlink_fmsg_bool_pair_put(fmsg, "stopped", stopped);
>  	devlink_fmsg_u32_pair_put(fmsg, "cc", sq->cc);
>  	devlink_fmsg_u32_pair_put(fmsg, "pc", sq->pc);
> -- 
LGTM
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@xxxxxxxxxxxxxxx>
> 2.38.1