Subject: Re: [PATCH net-next 07/10] mlx5e: Call skb_metadata_set when skb->data points past metadata

From: Jakub Sitnicki <[email-masked]>
Date: Tue, 13 Jan 2026 13:52:15 +0100

On Tue, Jan 13, 2026 at 08:08 AM +02, Tariq Toukan wrote:
> On 10/01/2026 23:05, Jakub Sitnicki wrote:
>> Prepare to copy the XDP metadata into an skb extension in skb_metadata_set.
>> Adjust the driver to pull from skb->data before calling skb_metadata_set.
>> Signed-off-by: Jakub Sitnicki <[email-masked]>
>> ---
>>   drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
>> b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
>> index 2b05536d564a..20c983c3ce62 100644
>> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
>> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
>> @@ -237,8 +237,8 @@ static struct sk_buff *mlx5e_xsk_construct_skb(struct mlx5e_rq *rq, struct xdp_b
>>   	skb_put_data(skb, xdp->data_meta, totallen);
>>     	if (metalen) {
>> -		skb_metadata_set(skb, metalen);
>>   		__skb_pull(skb, metalen);
>> +		skb_metadata_set(skb, metalen);
>>   	}
>>     	return skb;
>> 
>
> Patch itself is simple..
>
> I share my concerns about the perf impact of the series idea.
> Do you have some working PoC? Please share some perf numbers..

Sorry, nothing to show yet. I've shared more context in my reply to
Jakub [1].

The series itself is an interface cleanup, whether we end up needing it
for the metadata effort or not. Hence I wanted to salvage it from [2].

[1] https://lore.kernel.org/all/[email-masked]/
[2] https://lore.kernel.org/r/[email-masked]