[PATCH] net/netvsc: fix the calculation of checksums based on mbuf flag

[Long Li]

> Subject: Re: [PATCH] net/netvsc: fix the calculation of checksums based on
> mbuf flag
> 
> On Wed, Mar 23, 2022 at 5:28 AM <longli at linuxonhyperv.com> wrote:
> >
> > From: Long Li <longli at microsoft.com>
> >
> > The netvsc should use RTE_MBUF_F_TX_L4_MASK and check the value to
> > decide the correct way to calculate checksums.
> 
> It's better to describe what the impact for an application is.
> Do I understand correctly that UDP checksum offloading was broken?
> 
> 
> I guess you want this backported.
> Fixes: 4e9c73e96e83 ("net/netvsc: add Hyper-V network device")
> Cc: stable at dpdk.org

I'm sending V2 with the Fixes tag. 

Thanks,
Long

> 
> 
> >
> > Signed-off-by: Long Li <longli at microsoft.com>
> > ---
> >  drivers/net/netvsc/hn_rxtx.c | 13 +++++++++----
> >  1 file changed, 9 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/net/netvsc/hn_rxtx.c
> > b/drivers/net/netvsc/hn_rxtx.c index 028f176c7e..34f40be5b8 100644
> > --- a/drivers/net/netvsc/hn_rxtx.c
> > +++ b/drivers/net/netvsc/hn_rxtx.c
> > @@ -1348,8 +1348,11 @@ static void hn_encap(struct rndis_packet_msg
> *pkt,
> >                         *pi_data = NDIS_LSO2_INFO_MAKEIPV4(hlen,
> >                                                            m->tso_segsz);
> >                 }
> > -       } else if (m->ol_flags &
> > -                  (RTE_MBUF_F_TX_TCP_CKSUM |
> RTE_MBUF_F_TX_UDP_CKSUM | RTE_MBUF_F_TX_IP_CKSUM)) {
> > +       } else if ((m->ol_flags & RTE_MBUF_F_TX_L4_MASK) ==
> > +                       RTE_MBUF_F_TX_TCP_CKSUM ||
> > +                  (m->ol_flags & RTE_MBUF_F_TX_L4_MASK) ==
> > +                       RTE_MBUF_F_TX_UDP_CKSUM ||
> > +                  (m->ol_flags & RTE_MBUF_F_TX_IP_CKSUM)) {
> >                 pi_data = hn_rndis_pktinfo_append(pkt,
> NDIS_TXCSUM_INFO_SIZE,
> >                                                   NDIS_PKTINFO_TYPE_CSUM);
> >                 *pi_data = 0;
> > @@ -1363,9 +1366,11 @@ static void hn_encap(struct rndis_packet_msg
> *pkt,
> >                                 *pi_data |= NDIS_TXCSUM_INFO_IPCS;
> >                 }
> >
> > -               if (m->ol_flags & RTE_MBUF_F_TX_TCP_CKSUM)
> > +               if ((m->ol_flags & RTE_MBUF_F_TX_L4_MASK) ==
> > +                               RTE_MBUF_F_TX_TCP_CKSUM)
> >                         *pi_data |= NDIS_TXCSUM_INFO_MKTCPCS(hlen);
> > -               else if (m->ol_flags & RTE_MBUF_F_TX_UDP_CKSUM)
> > +               else if ((m->ol_flags & RTE_MBUF_F_TX_L4_MASK) ==
> > +                               RTE_MBUF_F_TX_UDP_CKSUM)
> >                         *pi_data |= NDIS_TXCSUM_INFO_MKUDPCS(hlen);
> >         }
> >
> > --
> > 2.32.0
> >
> 
> 
> --
> David Marchand