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Message-ID: <d55ed1f583c31df17e98300ca91996a2446f4523.camel@microchip.com>
Subject: Re: [PATCH net] net: sparx5: do not refer to skb after passing it on
From:   Steen Hegelund <steen.hegelund@microchip.com>
To:     Jakub Kicinski <kuba@kernel.org>
CC:     "David S. Miller" <davem@davemloft.net>,
        <UNGLinuxDriver@microchip.com>, <netdev@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        kernel test robot <lkp@intel.com>
Date:   Wed, 2 Feb 2022 09:23:00 +0100
In-Reply-To: <20220201200521.179857d7@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
References: <20220201143057.3533830-1-steen.hegelund@microchip.com>
         <20220201200521.179857d7@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
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Hi Jacub,

Thanks for the feedback.

I will update according to your suggestions.

BR
Steen

On Tue, 2022-02-01 at 20:05 -0800, Jakub Kicinski wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On Tue, 1 Feb 2022 15:30:57 +0100 Steen Hegelund wrote:
> > Do not try to use any SKB fields after the packet has been passed up in the
> > receive stack.
> > 
> > This error was reported as shown below:
> 
> No need to spell it out, the tags speak for themselves.
> 
> > Reported-by: kernel test robot <lkp@intel.com>
> > Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> > 
> 
> Drop this...
> 
> > Fixes: f3cad2611a77 (net: sparx5: add hostmode with phylink support)
> > 
> 
> and this empty line - all the tags should be together.
> 
> > Signed-off-by: Steen Hegelund <steen.hegelund@microchip.com>
> > ---
> >  drivers/net/ethernet/microchip/sparx5/sparx5_packet.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c
> > b/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c
> > index dc7e5ea6ec15..ebdce4b35686 100644
> > --- a/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c
> > +++ b/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c
> > @@ -145,8 +145,8 @@ static void sparx5_xtr_grp(struct sparx5 *sparx5, u8 grp, bool byte_swap)
> >       skb_put(skb, byte_cnt - ETH_FCS_LEN);
> >       eth_skb_pad(skb);
> >       skb->protocol = eth_type_trans(skb, netdev);
> > -     netif_rx(skb);
> >       netdev->stats.rx_bytes += skb->len;
> > +     netif_rx(skb);
> >       netdev->stats.rx_packets++;
> 
> sorry to nit pick - wouldn't it be neater if both the stats were
> updated together?  Looks a little strange that netif_rx() is in
> between the two now.
> 
> >  }
> > 
> > --
> > 2.35.1
> > 
>