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Subject: Re: [PATCH NET v4 3/7] ipv6: use skb_expand_head in ip6_xmit
To:     Christoph Paasch <christoph.paasch@gmail.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        David Ahern <dsahern@kernel.org>,
        Jakub Kicinski <kuba@kernel.org>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, kernel@openvz.org,
        Julian Wiedmann <jwi@linux.ibm.com>
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From:   Vasily Averin <vvs@virtuozzo.com>
Message-ID: <ff75b068-8165-a45c-0026-8b8f1c745213@virtuozzo.com>
Date:   Sat, 21 Aug 2021 09:21:25 +0300
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On 8/21/21 1:44 AM, Christoph Paasch wrote:
> (resend without html - thanks gmail web-interface...)
> On Fri, Aug 20, 2021 at 3:41 PM Christoph Paasch
>> AFAICS, this is because pskb_expand_head (called from
>> skb_expand_head) is not adjusting skb->truesize when skb->sk is set
>> (which I guess is the case in this particular scenario). I'm not
>> sure what the proper fix would be though...

Could you please elaborate?
it seems to me skb_realloc_headroom used before my patch called pskb_expand_head() too
and did not adjusted skb->truesize too. Am I missed something perhaps?

The only difference in my patch is that skb_clone can be not called, 
though I do not understand how this can affect skb->truesize.

Thank you,
	Vasily Averin