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From:   Lina Wang <lina.wang@mediatek.com>
To:     "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Alexei Starovoitov <ast@kernel.org>,
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        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
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        <willemb@google.com>, <edumazet@google.com>,
        <zhuoliang.zhang@mediatek.com>, <chao.song@mediatek.com>,
        "lina . wang" <lina.wang@mediatek.com>
Subject: Re: [PATCH] net: fix wrong network header length
Date:   Thu, 10 Feb 2022 19:56:34 +0800
Message-ID: <20220210115634.18563-1-lina.wang@mediatek.com>
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From: lina.wang <lina.wang@mediatek.com>

On Wed, 2022-02-09 at 17:06 -0800, Jakub Kicinski wrote:
> On Wed, 9 Feb 2022 18:25:07 +0800 lina.wang wrote:
> > We use NETIF_F_GRO_FRAGLIST not for forwarding scenary, just for
> > software udp gro. Whatever NETIF_F_GRO_FRAGLIST or NETIF_F_GRO_FWD,
> > skb_segment_list should not have bugs.
> > 
> > We modify skb_segment_list, not in epbf. One point is traversing
> > the
> > segments costly, another is what @Maciej said, *other* helper may
> > have
> > the same problem. In skb_segment_list, it calls
> > skb_headers_offset_update to update different headroom, which
> > implys
> > header maybe different.
> 
> Process notes:
>  - the patch didn't apply so even if the discussion concludes that 
>    the patch was good you'll need to rebase on netdev/net and repost;
>  - please don't top post.

I have rebased and reposted--
https://patchwork.kernel.org/project/netdevbpf/patch/20220210091655.17231-1-lina.wang@mediatek.com/, 
please check if it can apply.

Thanks!