Re: [dpdk-dev] [dpdk-stable] [PATCH 1/4] net/tap: fix Rx cksum flags on IP options packets

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 4/27/2021 2:57 PM, Olivier Matz wrote:
> When packet type is IPV4_EXT, the checksum is always marked as good in
> the mbuf offload flags.
> 
> Since we know the header lengths, we can easily call
> rte_ipv4_udptcp_cksum() in this case too.
> 
> Fixes: 8ae3023387e9 ("net/tap: add Rx/Tx checksum offload support")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
> ---
>  drivers/net/tap/rte_eth_tap.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index 68baa18523..e7b185a4b5 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -350,7 +350,7 @@ tap_verify_csum(struct rte_mbuf *mbuf)
>  		/* Don't verify checksum for multi-segment packets. */
>  		if (mbuf->nb_segs > 1)
>  			return;
> -		if (l3 == RTE_PTYPE_L3_IPV4) {
> +		if (l3 == RTE_PTYPE_L3_IPV4 || l3 == RTE_PTYPE_L3_IPV4_EXT) {

Should we take 'RTE_PTYPE_L3_IPV4_EXT_UNKNOWN' into account?

>  			if (l4 == RTE_PTYPE_L4_UDP) {
>  				udp_hdr = (struct rte_udp_hdr *)l4_hdr;
>  				if (udp_hdr->dgram_cksum == 0) {
> @@ -364,7 +364,7 @@ tap_verify_csum(struct rte_mbuf *mbuf)
>  				}
>  			}
>  			cksum = ~rte_ipv4_udptcp_cksum(l3_hdr, l4_hdr);
> -		} else if (l3 == RTE_PTYPE_L3_IPV6) {
> +		} else { /* l3 == RTE_PTYPE_L3_IPV6, checked above */
>  			cksum = ~rte_ipv6_udptcp_cksum(l3_hdr, l4_hdr);
>  		}
>  		mbuf->ol_flags |= cksum ?
>