On Fri, 17 Nov 2023 00:50:16 +0000 Ferruh Yigit <ferruh.yi...@amd.com> wrote:
> >> Hi Kaiwen, > >> > >> I am trying to understand the problem, what is the testcase that has > >> checksum error? > >> > >> Are the received mbuf data_len & pkt_len wrong? Instead of trying to fix > >> the mbuf during forwarding, can we fix where packet generated? > > > > The root cause is that get_udptcp_cksum_mbuf is using m->pkt_len > > which maybe larger than the actual data. The real issue is there and > > in rte_ip.h checksum code. The correct fix would be to use l3_len instead. > > > > I see, you are right. > > In 'rte_ipv4_udptcp_cksum_mbuf()', > as payload length "mbuf->pkt_len - l4_off" is used, which includes > padding and if padding is not zero it will end up producing wrong checksum. > > > I agree using 'l3_len' instead is correct fix. > > But this requires ABI/API change, > plus do we have any reason to keep the padding, discarding it as this > patch does is also simpler alternative. Possibly an API version to change the args would work to fix.
