[dpdk-stable] [PATCH] net: prepare the outer ipv4 hdr for checksum

[Kinsella, Ray]

Please mark [PATCH v2], and record changes under the ---

Ray K

> -----Original Message-----
> From: Mohsin Kazmi <mohsin.kazmi14 at gmail.com>
> Sent: Tuesday 29 June 2021 18:07
> To: dev at dpdk.org
> Cc: Kinsella, Ray <ray.kinsella at intel.com>; Mohsin Kazmi
> <mohsin.kazmi14 at gmail.com>; stable at dpdk.org; Olivier Matz
> <olivier.matz at 6wind.com>; Ananyev, Konstantin
> <konstantin.ananyev at intel.com>; Thomas Monjalon
> <thomas.monjalon at 6wind.com>; Tomasz Kulasek <tomaszx.kulasek at intel.com>
> Subject: [PATCH] net: prepare the outer ipv4 hdr for checksum
> 
> Preparation the headers for the hardware offload misses the outer ipv4
> checksum offload.
> It results in bad checksum computed by hardware NIC.
> 
> This patch fixes the issue by setting the outer ipv4 checksum field to
> 0.
> 
> Fixes: 4fb7e803eb1a ("ethdev: add Tx preparation")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Mohsin Kazmi <mohsin.kazmi14 at gmail.com>
> Acked-by: Qi Zhang <qi.z.zhang at intel.com>
> ---
>  lib/net/rte_net.h | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/net/rte_net.h b/lib/net/rte_net.h index
> 434435ffa2..e47365099e 100644
> --- a/lib/net/rte_net.h
> +++ b/lib/net/rte_net.h
> @@ -128,8 +128,18 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf
> *m, uint64_t ol_flags)
>  	if (!(ol_flags & (PKT_TX_IP_CKSUM | PKT_TX_L4_MASK |
> PKT_TX_TCP_SEG)))
>  		return 0;
> 
> -	if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6))
> +	if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6)) {
>  		inner_l3_offset += m->outer_l2_len + m->outer_l3_len;
> +		/*
> +		 * prepare outer ipv4 header checksum by setting it to 0,
> +		 * in order to be computed by hardware NICs.
> +		 */
> +		if (ol_flags & PKT_TX_OUTER_IP_CKSUM) {
> +			ipv4_hdr = rte_pktmbuf_mtod_offset(m,
> +					struct rte_ipv4_hdr *, m->outer_l2_len);
> +			ipv4_hdr->hdr_checksum = 0;
> +		}
> +	}
> 
>  	/*
>  	 * Check if headers are fragmented.
> --
> 2.17.1