Environment
===========
DPDK version: 9fe9c0b231c8da5435bfccb1963121b4277f961c version: dpdk25.07-rc3
OS: Fedora42/6.14.5-300.fc42.x86_64
Compiler: gcc version 15.1.1 20250425
Hardware platform: Intel(R) Xeon(R) Gold 6252N CPU @ 2.30GHz
NIC hardware: Intel Corporation Ethernet Controller X710 for 10GbE SFP+ (rev
01)
NIC firmware: 
  driver: vfio-pci
  kdriver: i40e-2.28.7
  firmware-version: 9.54 0x8000fb3f 1.3800.0

Test Setup
Steps to reproduce
==================
1.dut start testpmd
usertools/dpdk-devbind.py --force --bind=vfio-pci 0000:31:00.0 0000:31:00.1
x86_64-native-linuxapp-gcc/app/dpdk-testpmd  -l 1-5 -n 4 -a 0000:31:00.0 -a
0000:31:00.1  --file-prefix=dpdk_187982_20250711151456    
--force-max-simd-bitwidth=64   -- -i --disable-rss --rxq=4 --txq=4 --nb-cores=4
--portmask=0x3 --enable-rx-cksum

testpmd> vlan set filter off 0
testpmd> set verbose 1
testpmd> set fwd csum
testpmd> port stop all
testpmd> csum set ip hw 1
testpmd> csum set udp hw 1
testpmd> csum set tcp hw 1
testpmd> csum set sctp hw 1
testpmd> csum set outer-ip hw 1
testpmd> csum parse-tunnel on 1
testpmd> port start all
testpmd> start

2. start tester scapy_0 to save the capture packet
scapy
>>> p=sniff(iface="ens9f1",filter="ether[12:2]!=0x88cc",timeout=10)

3. start tester scapy_1 send pkt with error ip.checksum 0x1234
scapy
>>> p = Ether(dst='3c:fd:fe:c0:e1:d8', src='00:00:10:00:00:00')/IP(frag=0,
>>> src='192.168.1.1', dst='192.168.1.2')/GRE(key_present=1,
>>> key=0x100)/Ether(dst='90:e2:ba:4a:34:89', src='90:e2:ba:4a:34:88',
>>> type=0x0800)/IP(frag=0, chksum=0x1234, src='192.168.2.1',
>>> dst='192.168.2.2')/UDP(sport=1021,
>>> dport=1021)/Raw(load=b'XXXXXXXXXXXXXXXXXX')
>>> sendp(p, iface="ens9f0")

4. save the capture packet into pcap format in tester scapy_0
>>> wrpcap("/root/capture.pcap", p)

5. check ip.checksum in tester
tshark -r /root/capture.pcap -T fields -e ip.checksum

Results: 
========
0x1234 is in output.

Expected Result:
================
0xf56a is in output.

bad commit:
===========
commit a738c43ffaee9ba5d8eccb0e881e7c816d3c6415
Author: Dengdui Huang <huangdengdui@huawei.com>
Date:   Mon Jun 16 16:27:02 2025 +0800



    app/testpmd: fix tunnel inner info

    The l2_len field of tunnel packets already includes the tunnel_len field.
    Additionally, the current offset used for the internal Ethernet header is
    incorrect. This patch fixes these issues.

    Fixes: 76730c7b9b5a ("app/testpmd: use packet type parsing API")
    Cc: stable@dpdk.org

    Signed-off-by: Dengdui Huang <huangdengdui@huawei.com>