Please we need more reviews for this patch.

I'll update the patch and post a v2.

19/07/2021 10:33, Gregory Etelson:

quoted

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.

quoted

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@dpdk.org

nit: no blank line between Fixes and Cc lines please

quoted

Signed-off-by: Gregory Etelson <redacted>
Reviewed-by: Dmitry Kozlyuk <redacted>
---
+                     } else if (ipv4_hdr->hdr_checksum) {

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

quoted

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