Re: [PATCH v5 net-next 05/14] tcp: L4S ECT(1) identifier and NEEDS_ACCECN for CC modules

On 10/30/25 3:34 PM, chia-yu.chang@nokia-bell-labs.com wrote:

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 7f5df7a71f62..d475f80b2248 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -328,12 +328,17 @@ static void tcp_ecn_send(struct sock *sk, struct sk_buff *skb, struct tcphdr *th, int tcp_header_len) { struct tcp_sock *tp = tcp_sk(sk);

• bool ecn_ect_1;

if (!tcp_ecn_mode_any(tp)) return;

• ecn_ect_1 = tp->ecn_flags & TCP_ECN_ECT_1;
• if (ecn_ect_1 && !tcp_accecn_ace_fail_recv(tp))

• __INET_ECN_xmit(sk, true);
  

I'm possibly lost, but I can't find ecn_flags TCP_ECN_ECT_1 bit being set here or elsewhere in this series.

Also why isn't this chunk under `if (tcp_ecn_mode_accecn(tp))` ?

/P