Subject: Re: [PATCH net-next 00/10] Call skb_metadata_set when skb->data points past metadata

From: Jakub Kicinski <[email-masked]>
Date: Mon, 12 Jan 2026 19:08:56 -0800

On Sat, 10 Jan 2026 22:05:14 +0100 Jakub Sitnicki wrote:
> This series is split out of [1] following discussion with Jakub.
> 
> To copy XDP metadata into an skb extension when skb_metadata_set() is
> called, we need to locate the metadata contents.

"When skb_metadata_set() is called"? I think that may cause perf
regressions unless we merge major optimizations at the same time?
Should we defer touching the drivers until we have a PoC and some
idea whether allocating the extension right away is manageable or 
we are better off doing it via a kfunc in TC (after GRO)?
To be clear putting the metadata in an extension right away would
indeed be much cleaner, just not sure how much of the perf hit we 
can optimize away..