From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Kicinski <jakub.kicinski@netronome.com>
Subject: Re: [PATCH bpf-next 08/10] [bpf]: make netronome nfp compatible w/
 bpf_xdp_adjust_tail
Date: Tue, 17 Apr 2018 17:40:51 -0700
Message-ID: <20180417174051.6b4c7fb2@cakuba.netronome.com>
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        <20180417065131.3632-9-tehnerd@tehnerd.com>
        <20180417230828.p745neslgxoy5fus@ast-mbp>
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Cc: "Nikita V. Shirokov" <tehnerd@tehnerd.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>, netdev@vger.kernel.org
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
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On Tue, 17 Apr 2018 16:08:29 -0700, Alexei Starovoitov wrote:
> On Mon, Apr 16, 2018 at 11:51:29PM -0700, Nikita V. Shirokov wrote:
> > w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
> > well (only "decrease" of pointer's location is going to be supported).
> > changing of this pointer will change packet's size.
> > for nfp driver we will just calculate packet's length unconditionally
> > 
> > Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
> > ---
> >  drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> > index 1eb6549f2a54..d9111c077699 100644
> > --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> > +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> > @@ -1722,7 +1722,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
> >  
> >  			act = bpf_prog_run_xdp(xdp_prog, &xdp);
> >  
> > -			pkt_len -= xdp.data - orig_data;
> > +			pkt_len = xdp.data_end - xdp.data;  
> 
> Looks correct, but Jakub please review.

Indeed:

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>

Thanks!