From nobody Sun Mar 22 10:12:32 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B1755363C63; Mon, 9 Mar 2026 08:03:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773043426; cv=none; b=D1e4HZK3n59WHZ9f2qHn52ODD+NRu2Gj1rA0MlsKgQiUehWt5eh17+/4RR1VB8H7WejJf48qY/IT9Oo0J+r0X+yqoZj4d7b+KVB6pi0L1O+ClO4X8NqW3Cn8+upxOnb9L2w1a8uCK9B5L491ye8NepIeGQF0nAAzddNAZ09Bh44= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773043426; c=relaxed/simple; bh=U6eOZs3iNxBCZqrgik+0s/86JK4oBEk09rxPxv6C1jc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=O1OI1Md9Nz9xlujJ+bagvEJpng3jUleXB5jFT9BcG+lwmER4vX4bOmwAj5hEPvuVqYdKWeM1SdPvYvGxzRSck7O3/j1n1+w3srrpbtugiAbxiZ6ZWQg/z3SJ/D430d09v5Hs1jkj9ryxDNVXg93td2eG5pthSFzyj0IavX0629I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Vhjxp+Tz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Vhjxp+Tz" Received: by smtp.kernel.org (Postfix) with ESMTPS id 6EB55C2BC87; Mon, 9 Mar 2026 08:03:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773043426; bh=U6eOZs3iNxBCZqrgik+0s/86JK4oBEk09rxPxv6C1jc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=Vhjxp+TzGcrl9Uu+gCftb9lUUbQwVQq3qygNlH4kUhLqY827Ph0rKVqKGnjPfgfqH NQLCgWuLPGkZOB1Cz6aIa3a29sRLeUX3Xmo/4j8sb31WL4vSN87TkcxOhkg6T8ptB0 8IQNtKBjZqADri0bWm8qgqfFWMjbXMeej1e8yThK7JMCLbHLkN1wwM1VWbXJGEUzf2 jZASe+9elgTFryZ3gc6a3vLm8KmoJuQOn/Ne3AuuXcpWOu1aXLSNhrWGxs65Vk0+BO PTT0wDcJzNLQflk399xUD4I+RsqxjBHbCD9s6G0zBRb0CU+IG832svcsdP5sqmxSlV p0bKeHKK+GhXQ== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5D591EF36FB; Mon, 9 Mar 2026 08:03:46 +0000 (UTC) From: Simon Baatz via B4 Relay Date: Mon, 09 Mar 2026 09:02:27 +0100 Subject: [PATCH net-next v3 2/6] mptcp: keep rcv_mwnd_seq in sync with subflow rcv_wnd Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260309-tcp_rfc7323_retract_wnd_rfc-v3-2-4c7f96b1ec69@gmail.com> References: <20260309-tcp_rfc7323_retract_wnd_rfc-v3-0-4c7f96b1ec69@gmail.com> In-Reply-To: <20260309-tcp_rfc7323_retract_wnd_rfc-v3-0-4c7f96b1ec69@gmail.com> To: Eric Dumazet , Neal Cardwell , Kuniyuki Iwashima , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Shuah Khan , David Ahern , Jon Maloy , Jason Xing , mfreemon@cloudflare.com, Shuah Khan , Stefano Brivio , Matthieu Baerts , Mat Martineau , Geliang Tang Cc: netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, mptcp@lists.linux.dev, Simon Baatz X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1773043425; l=1316; i=gmbnomis@gmail.com; s=20260220; h=from:subject:message-id; bh=ChftbPgxBgowAH5jlThlLmD2ZcIdQ5MNv0dOVMZk0bc=; b=ebwxj9jswhY7N+FX93x/tqn0TUOf6ljdixhMtvB9X8ZTBTSLzUET9CMuG0w7U6djoehuAO9z1 K6f847zwt1VANVMgE8WgLKsGJzlx1Qb2yKGdLXsQZf0vswy9hFLWe/W X-Developer-Key: i=gmbnomis@gmail.com; a=ed25519; pk=T/JIz/6F5bf1uQJr69lmyi7czVG+F9TVZ/8x5z9Wtqw= X-Endpoint-Received: by B4 Relay for gmbnomis@gmail.com/20260220 with auth_id=641 X-Original-From: Simon Baatz Reply-To: gmbnomis@gmail.com From: Simon Baatz MPTCP shares a receive window across subflows and applies it at the subflow level by adjusting each subflow's rcv_wnd when needed. With the new TCP tracking of the maximum advertised window sequence, rcv_mwnd_seq must stay consistent with these subflow-level rcv_wnd adjustments. Signed-off-by: Simon Baatz Reviewed-by: Eric Dumazet Reviewed-by: Matthieu Baerts (NGI0) --- net/mptcp/options.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 43df4293f58bfbd8a8df6bf24b9f15e0f9e238f6..8a1c5698983cff3082d68290626= dd8f1e044527f 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -1076,6 +1076,7 @@ static void rwin_update(struct mptcp_sock *msk, struc= t sock *ssk, * resync. */ tp->rcv_wnd +=3D mptcp_rcv_wnd - subflow->rcv_wnd_sent; + tcp_update_max_rcv_wnd_seq(tp); subflow->rcv_wnd_sent =3D mptcp_rcv_wnd; } =20 @@ -1338,8 +1339,9 @@ static void mptcp_set_rwin(struct tcp_sock *tp, struc= t tcphdr *th) */ rcv_wnd_new =3D rcv_wnd_old; win =3D rcv_wnd_old - ack_seq; - tp->rcv_wnd =3D min_t(u64, win, U32_MAX); - new_win =3D tp->rcv_wnd; + new_win =3D min_t(u64, win, U32_MAX); + tp->rcv_wnd =3D new_win; + tcp_update_max_rcv_wnd_seq(tp); =20 /* Make sure we do not exceed the maximum possible * scaled window. --=20 2.53.0