Re: [PATCH v5 net-next 2/2] net: hns3: fix GSO_ECN flag setting in the RX path

Jijie Shao <[email protected]> Thu, 6 Aug 2026 19:47:00 +0800

Newsgroups	dev.linux.lists.virtualization,org.kernel.vger.bpf,org.kernel.vger.linux-doc,org.kernel.vger.linux-kselftest,org.kernel.vger.linux-rdma,org.kernel.vger.netdev
Message-ID	<[email protected]>

on 2026/8/5 5:35, [email protected] wrote:
> From: Chia-Yu Chang <[email protected]>
>
> Currently, the hns3 Rx path sets the SKB_GSO_TCP_ECN flag when a TCP
> segment with the CWR flag set is received. This is incorrect because
> the hns3 hardware GRO resets the IP ToS byte to 0 during packet
> aggregation. Consequently, no valid ECN signals are carreid, meaning
> that it cannot support RFC3168 ECN or Accurate ECN protocols. Setting
> SKB_GSO_TCP_ECN or SKB_GSO_TCP_ACCECN under these conditions misleads
> the upper network stack.
>
> Fix this by removing the incorrect SKB_GSO_TCP_ECN flag assignment
> in hns3_gro_complete().
>
> Fixes: d474d88f88261 ("net: hns3: add hns3_gro_complete for HW GRO process")

One note:
since this patch fixes a bug (incorrect SKB_GSO_TCP_ECN flag set in hns3_gro_complete),
it should target net instead of net-next.

I'm running HW tests on hns3 to verify the fix. Will share results
based on what I observe.

Thanks,
Jijie Shao