Re: [PATCH v9 net-next 05/15] tcp: disable RFC3168 fallback identifier for CC modules
From: Eric Dumazet <edumazet@google.com>
Date: 2026-01-20 09:56:51
Also in:
bpf, linux-doc, linux-kselftest
On Mon, Jan 19, 2026 at 7:59 PM [off-list ref] wrote:
From: Chia-Yu Chang <redacted> When AccECN is not successfully negociated for a TCP flow, it defaults fallback to classic ECN (RFC3168). However, L4S service will fallback to non-ECN. This patch enables congestion control module to control whether it should not fallback to classic ECN after unsuccessful AccECN negotiation. A new CA module flag (TCP_CONG_NO_FALLBACK_RFC3168) identifies this behavior expected by the CA. Signed-off-by: Chia-Yu Chang <redacted> Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>