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Date: Thu, 13 Aug 2026 18:27:44 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Xin Xie <xiexinet@gmail.com>
Cc: davem@davemloft.net, pabeni@redhat.com, edumazet@google.com,
 horms@kernel.org, shuah@kernel.org, lukma@denx.de, m-karicheri2@ti.com,
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 ali@iusegentoo.com, qingfang.deng@linux.dev, netdev@vger.kernel.org,
 linux-kselftest@vger.kernel.org
Subject: Re: [PATCH net v3 1/3] net: hsr: privatize interlink-bound skbs
 before address mutation
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On Sat,  8 Aug 2026 02:45:22 +0200 Xin Xie wrote:
> +	if (port->type == HSR_PT_INTERLINK &&
> +	    (frame->port_rcv->type == HSR_PT_MASTER ||
> +	     (frame->is_local_dest && !frame->is_local_exclusive)) &&
> +	    skb_cow(skb, 0)) {

Would skb_cow_head() be sufficient? It's much cheaper, at least for TCP.