From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: unexpected GRO/veth behavior
Date: Tue, 11 Sep 2018 08:42:42 -0700
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Cc: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
To: Paolo Abeni <pabeni@redhat.com>,
        Eric Dumazet <eric.dumazet@gmail.com>, netdev@vger.kernel.org
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On 09/11/2018 04:44 AM, Paolo Abeni wrote:
> On Tue, 2018-09-11 at 03:27 -0700, Eric Dumazet wrote:
>> On 09/10/2018 11:54 PM, Paolo Abeni wrote:
>>> I *think* we can hit a similar condition with a tun device in IFF_NAPI
>>> mode.
>>
>> Why ?
>>
>> tun_get_user() does not attach skb to a socket, that would be quite useless since skb
>>
> 	
> I think we can hit this code path:
> 
> tun_get_user() -> tun_alloc_skb() -> sock_alloc_send_pskb() ->
> skb_set_owner_w() 
> 
> Than later napi and GRO.
> 


No we can not.

Please look again.