Re: [PATCH v2] net: mlx5: vport: Add error handling in mlx5_query_nic_vport_node_guid()

[Tariq Toukan <ttoukan.linux@gmail.com>]

Prefer 'net/mlx5' prefix for mlx5_core patches.

On 19/05/2025 12:09, Wentao Liang wrote:

V2 respinned too quickly.
Please hold at least 24 hours between respins.

> The function mlx5_query_nic_vport_node_guid() calls the function
> mlx5_query_nic_vport_context() but does not check its return value.
> A proper implementation can be found in mlx5_nic_vport_query_local_lb().
> 
> Add error handling for mlx5_query_nic_vport_context(). If it fails, free
> the out buffer via kvfree() and return error code.
> 
> Fixes: 9efa75254593 ("net/mlx5_core: Introduce access functions to query vport RoCE fields")
> Cc: stable@vger.kernel.org # v4.5
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>

Explicitly mention target branch.

> ---
> v2: Remove redundant reassignment. Fix typo error.
> 
>   drivers/net/ethernet/mellanox/mlx5/core/vport.c | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/vport.c b/drivers/net/ethernet/mellanox/mlx5/core/vport.c
> index ded086ffe8ac..8235fa6add03 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/vport.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/vport.c
> @@ -465,19 +465,22 @@ int mlx5_query_nic_vport_node_guid(struct mlx5_core_dev *mdev, u64 *node_guid)
>   {
>   	u32 *out;
>   	int outlen = MLX5_ST_SZ_BYTES(query_nic_vport_context_out);
> +	int ret;

Let's be consistent with existing convention in this file.
There are many similar examples.

Use local variable 'err', and label 'out'.

>   
>   	out = kvzalloc(outlen, GFP_KERNEL);
>   	if (!out)
>   		return -ENOMEM;
>   
> -	mlx5_query_nic_vport_context(mdev, 0, out);
> +	ret = mlx5_query_nic_vport_context(mdev, 0, out);
> +	if (ret)
> +		goto err;
>   
>   	*node_guid = MLX5_GET64(query_nic_vport_context_out, out,
>   				nic_vport_context.node_guid);
> -
> +err:
>   	kvfree(out);
>   
> -	return 0;
> +	return ret;
>   }
>   EXPORT_SYMBOL_GPL(mlx5_query_nic_vport_node_guid);
>