[dpdk-dev] [PATCH] net/failsafe: fix source port ID in Rx packets

[David Marchand]

Hey Adrien,

On Thu, Apr 18, 2019 at 3:12 PM Adrien Mazarguil <adrien.mazarguil at 6wind.com>
wrote:

> When passed to the application, Rx packets retain the port ID value
> originally set by slave devices. Unfortunately these IDs have no meaning to
> applications, which are typically unaware of their existence.
>
> This confuses those caring about the source port field in mbufs (m->port)
> which experience issues ranging from traffic drop to crashes.
>
> Fixes: a46f8d584eb8 ("net/failsafe: add fail-safe PMD")
>

Cc: stable at dpdk.org

Signed-off-by: Adrien Mazarguil <adrien.mazarguil at 6wind.com>
> ---
>  drivers/net/failsafe/failsafe_rxtx.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
>
> diff --git a/drivers/net/failsafe/failsafe_rxtx.c
> b/drivers/net/failsafe/failsafe_rxtx.c
> index 231c83291..e78624127 100644
> --- a/drivers/net/failsafe/failsafe_rxtx.c
> +++ b/drivers/net/failsafe/failsafe_rxtx.c
> @@ -61,6 +61,21 @@ failsafe_set_burst_fn(struct rte_eth_dev *dev, int
> force_safe)
>         rte_wmb();
>  }
>
> +/*
> + * Override source port in Rx packets.
> + *
> + * Make Rx packets originate from this PMD instance instead of one of its
> + * slaves. This is mandatory to avoid breaking applications.
> + */
> +static void
> +failsafe_rx_set_port(struct rte_mbuf **rx_pkts, uint16_t nb_pkts,
> uint16_t port)
> +{
> +       unsigned int i;
> +
> +       for (i = 0; i != nb_pkts; ++i)
> +               rx_pkts[i]->port = port;
> +}
> +
>  uint16_t
>  failsafe_rx_burst(void *queue,
>                   struct rte_mbuf **rx_pkts,
> @@ -87,6 +102,9 @@ failsafe_rx_burst(void *queue,
>                 sdev = sdev->next;
>         } while (nb_rx == 0 && sdev != rxq->sdev);
>         rxq->sdev = sdev;
> +       if (nb_rx)
> +               failsafe_rx_set_port(rx_pkts, nb_rx,
> +                                    rxq->priv->dev->data->port_id);
>         return nb_rx;
>  }
>
> @@ -112,6 +130,9 @@ failsafe_rx_burst_fast(void *queue,
>                 sdev = sdev->next;
>         } while (nb_rx == 0 && sdev != rxq->sdev);
>         rxq->sdev = sdev;
> +       if (nb_rx)
> +               failsafe_rx_set_port(rx_pkts, nb_rx,
> +                                    rxq->priv->dev->data->port_id);
>         return nb_rx;
>  }
>
> --
> 2.11.0
>

Not a big fan of those duplicated rx_burst functions...
Reviewed-by: David Marchand <david.marchand at redhat.com>

I suppose the bonding pmd has the same issue.

-- 
David Marchand