[dpdk-stable] [dpdk-dev] [PATCH] app/testpmd: fix TX checksum calculation for tunnel

[Thomas Monjalon]

Please we need more reviews for this patch.

19/07/2021 10:33, Gregory Etelson:
> TX checksum of a tunnelled packet can be calculated for outer headers
> only or for both outer and inner parts. The calculation method is
> determined by application.
> If TX checksum calculation can be offloaded, hardware ignores
> existing checksum value and replaces it with an updated result.
> If TX checksum is calculated by a software, existing value must be
> zeroed first.
> The testpmd checksum forwarding engine always zeroed inner checksums.
> If inner checksum calculation was offloaded, that header was left
> with 0 checksum value.
> Following outer software checksum calculation produced wrong value.
> The patch zeroes inner IPv4 checksum only before software calculation.
> 
> Fixes: 51f694dd40f5 ("app/testpmd: rework checksum forward engine")
> 
> Cc: stable at dpdk.org

nit: no blank line between Fixes and Cc lines please

> 
> Signed-off-by: Gregory Etelson <getelson at nvidia.com>
> Reviewed-by: Dmitry Kozlyuk <dmitry.kozliuk at gmail.com>
> ---
> +			} else if (ipv4_hdr->hdr_checksum) {

Please do an explicit comparison with 0 here
as it cannot be considered as a boolean test.

> +				ipv4_hdr->hdr_checksum = 0;
>  				ipv4_hdr->hdr_checksum =
>  					rte_ipv4_cksum(ipv4_hdr);
> +			}