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Date:   Tue, 15 Mar 2022 21:50:12 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Menglong Dong <menglong8.dong@gmail.com>
Cc:     David Ahern <dsahern@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>, xeb@mail.ru,
        David Miller <davem@davemloft.net>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Menglong Dong <imagedong@tencent.com>,
        Eric Dumazet <edumazet@google.com>, Martin Lau <kafai@fb.com>,
        Talal Ahmad <talalahmad@google.com>,
        Kees Cook <keescook@chromium.org>,
        Alexander Lobakin <alobakin@pm.me>,
        Hao Peng <flyingpeng@tencent.com>,
        Mengen Sun <mengensun@tencent.com>, dongli.zhang@oracle.com,
        LKML <linux-kernel@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>,
        Biao Jiang <benbjiang@tencent.com>
Subject: Re: [PATCH net-next 1/3] net: gre_demux: add skb drop reasons to
 gre_rcv()
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On Wed, 16 Mar 2022 12:41:45 +0800 Menglong Dong wrote:
> > On Mon, 14 Mar 2022 21:33:10 +0800 menglong8.dong@gmail.com wrote:  
> > > +     reason = SKB_DROP_REASON_NOT_SPECIFIED;
> > >       if (!pskb_may_pull(skb, 12))
> > >               goto drop;  
> >
> > REASON_HDR_TRUNC ?  
> 
> I'm still not sure about such a 'pskb_pull' failure, whose reasons may be
> complex, such as no memory or packet length too small. I see somewhere
> return a '-NOMEM' when skb pull fails.
> 
> So maybe such cases can be ignored? In my opinion, not all skb drops
> need a reason.

Ah, okay, I saw Dave's email as well. I wasn't sure if this omission
was intentional. But if it is, that's fine.