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Date:   Sat, 16 Jan 2021 19:13:00 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Alexander Duyck <alexander.duyck@gmail.com>,
        Xin Long <lucien.xin@gmail.com>
Cc:     network dev <netdev@vger.kernel.org>,
        "linux-sctp @ vger . kernel . org" <linux-sctp@vger.kernel.org>,
        Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
        Neil Horman <nhorman@tuxdriver.com>
Subject: Re: [PATCHv3 net-next 1/2] net: move the hsize check to the else
 block in skb_segment
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References: <cover.1610703289.git.lucien.xin@gmail.com>
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On Fri, 15 Jan 2021 17:39:02 -0800 Alexander Duyck wrote:
> On Fri, Jan 15, 2021 at 1:36 AM Xin Long <lucien.xin@gmail.com> wrote:
> >
> > After commit 89319d3801d1 ("net: Add frag_list support to skb_segment"),
> > it goes to process frag_list when !hsize in skb_segment(). However, when
> > using skb frag_list, sg normally should not be set. In this case, hsize
> > will be set with len right before !hsize check, then it won't go to
> > frag_list processing code.
> >
> > So the right thing to do is move the hsize check to the else block, so
> > that it won't affect the !hsize check for frag_list processing.
> >
> > v1->v2:
> >   - change to do "hsize <= 0" check instead of "!hsize", and also move
> >     "hsize < 0" into else block, to save some cycles, as Alex suggested.
> >
> > Signed-off-by: Xin Long <lucien.xin@gmail.com>  
> 
> Looks good to me.
> 
> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>

Applied, thanks!