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Date: Tue, 17 Oct 2023 22:02:07 +0200
From: Florian Westphal <fw@strlen.de>
To: Yan Zhai <yan@cloudflare.com>
Cc: netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
	David Ahern <dsahern@kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Aya Levin <ayal@nvidia.com>, Tariq Toukan <tariqt@nvidia.com>,
	linux-kernel@vger.kernel.org, kernel-team@cloudflare.com,
	Florian Westphal <fw@strlen.de>,
	Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Subject: Re: [PATCH v2 net-next] ipv6: avoid atomic fragment on GSO packets
Message-ID: <20231017200207.GA5770@breakpoint.cc>
References: <ZS1/qtr0dZJ35VII@debian.debian>
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	lindbergh.monkeyblade.net

Yan Zhai <yan@cloudflare.com> wrote:
> Refactor __ip6_finish_output code to separate GSO and non-GSO packet
> processing. It mirrors __ip_finish_output logic now. Add an extra check
> in GSO handling to avoid atomic fragments. Lastly, drop dst_allfrag
> check, which is no longer true since commit 9d289715eb5c ("ipv6: stop
> sending PTB packets for MTU < 1280").
 

> -	if ((skb->len > mtu && !skb_is_gso(skb)) ||
> -	    dst_allfrag(skb_dst(skb)) ||

My preference is to first remove dst_allfrag, i.e. do this in
a separate change.