-----Original Message-----
From: Gregory Etelson <redacted>
Sent: Tuesday, July 27, 2021 21:08
To: dev@dpdk.org
Cc: getelson@nvidia.com; Ajit Khaparde <ajit.khaparde@broadcom.com>;
Olivier Matz [off-list ref]; Andrew Rybchenko
[off-list ref]; Yigit, Ferruh [off-list ref];
Thomas Monjalon [off-list ref]; stable@dpdk.org; Li, Xiaoyun
[off-list ref]
Subject: [PATCH v2] app/testpmd: fix TX checksum calculation for tunnel

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@dpdk.org

Signed-off-by: Gregory Etelson <redacted>
---
v2:
 remove blank line between Fixes and Cc
 explicitly compare with 0 value in `if ()`
---
 app/test-pmd/csumonly.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

Acked-by: Xiaoyun Li <redacted>