Re: [dpdk-stable] [PATCH] net/virtio: fix device configure without jumbo Rx offload

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 9/2/21 4:39 PM, Andrew Rybchenko wrote:
> From: Ivan Ilchenko <Ivan.Ilchenko@oktetlabs.ru>
> 
> Use max-pkt-len only if jumbo frames offload is requested
> since otherwise this field isn't valid.
> 
> Fixes: 8b90e4358112 ("net/virtio: set offload flag for jumbo frames")
> Fixes: 4e8169eb0d2d ("net/virtio: fix Rx scatter offload")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Ivan Ilchenko <ivan.ilchenko@oktetlabs.ru>
> Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> ---
>  drivers/net/virtio/virtio_ethdev.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
> index e58085a2c9..9bce6833db 100644
> --- a/drivers/net/virtio/virtio_ethdev.c
> +++ b/drivers/net/virtio/virtio_ethdev.c
> @@ -2099,10 +2099,14 @@ virtio_dev_configure(struct rte_eth_dev *dev)
>  			return ret;
>  	}
>  
> -	if (rxmode->max_rx_pkt_len > hw->max_mtu + ether_hdr_len)
> +	if ((rx_offloads & DEV_RX_OFFLOAD_JUMBO_FRAME) &&
> +	    (rxmode->max_rx_pkt_len > hw->max_mtu + ether_hdr_len))
>  		req_features &= ~(1ULL << VIRTIO_NET_F_MTU);
>  
> -	hw->max_rx_pkt_len = rxmode->max_rx_pkt_len;
> +	if (rx_offloads & DEV_RX_OFFLOAD_JUMBO_FRAME)
> +		hw->max_rx_pkt_len = rxmode->max_rx_pkt_len;
> +	else
> +		hw->max_rx_pkt_len = ether_hdr_len + dev->data->mtu;
>  
>  	if (rx_offloads & (DEV_RX_OFFLOAD_UDP_CKSUM |
>  			   DEV_RX_OFFLOAD_TCP_CKSUM))
> 

Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Thanks,
Maxime