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Date: Tue, 4 Aug 2026 16:43:24 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: Qihang <q.h.hack.winter@gmail.com>, netdev@vger.kernel.org,
 daniel.zahka@gmail.com, davem@davemloft.net, edumazet@google.com,
 pabeni@redhat.com, horms@kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH net v5 2/2] packet: use consistent hard_header_len in
 TX_RING send path
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On Mon, 03 Aug 2026 23:04:54 -0400 Willem de Bruijn wrote:
> If I read Gemini feedback correctly, all reports are about the current
> solution falling short of fixing the instance of this race condition
> with dev_hard_header(), which reads dev->hard_header_len directly.
> The patch indeed mentions this limitation.

To be clear -- prefer looking that the netdev-ai instance.
It cross reviews the feedback with different LLMs

> As well as the same issue with dev_validate_header(), which the commit
> does not list as limitation. But that one is only reached with variable
> length L2 protocols.
> 
> Side note, in net-next I can probably remove header_ops.validate now
> that ax25 is gone, and with that all of dev_validate_header. No other
> variable length L2 protocol ever implemented that callback.

Let's do it.