From nobody Mon Dec 15 00:33:11 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 12B613002B6 for ; Wed, 3 Dec 2025 18:25:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764786320; cv=none; b=OsMA6BMgTdQ8I3LIPnmJpRDPRs7QtSkmzX8j+kZ1OBnyCaZmknKZ0Gi6muLXFRNqt8P3TmZsCOGCwfeHT2CCFfFzr157PZwzoOBDsLs/men2hYmz1/PBozVxGz+wxMPlcmzxAWXDGTwtPZH3r4X3UShbc4vfynibIdvKHF8+66E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764786320; c=relaxed/simple; bh=OPc1i2YcovizJrx5xij2KqBskEdciCOX8oKORmsRCAA=; h=From:To:Subject:Date:Message-ID:MIME-Version:content-type; b=YFBoYQdeTsugUBFfb8enGCczrHk/wm95zpnuryBjbaSJq2OabJ9fKHYjldTtwBvAcaGa0IJ6ciP3en12xj8xUkjg0YSZH81mRb0GXR5Sh9mbrQ68cxUgjSdyq8G1GGQCyUpIyzFrC9WKg3tdbvhbk1vviFNi7Il9g0lsvbCyUok= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=HZd9amrl; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HZd9amrl" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1764786316; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=xkRFqC/bBLytnxktmVT3PdAanA4cZb3w97brVIkmnsY=; b=HZd9amrlsZXuMiyCei4mUjs8hEYmLoM2kiHbfVn9+SsP3t2NlkqKvu0E5LTkA7RTtabWXQ +ghdPQp/Dsd8UiaDxjeLmjP96+Hj9xOiwd15E1QwGrae4/43LBfmUeXrGnkrMW21A6+/jj gjaOeDTsUv0QzmAkn1vAgqlGa/RqhUg= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-381-BdLgJ4VHMr6VpjmpCmRIcg-1; Wed, 03 Dec 2025 13:25:15 -0500 X-MC-Unique: BdLgJ4VHMr6VpjmpCmRIcg-1 X-Mimecast-MFC-AGG-ID: BdLgJ4VHMr6VpjmpCmRIcg_1764786314 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 27F6F180060D for ; Wed, 3 Dec 2025 18:25:14 +0000 (UTC) Received: from gerbillo.redhat.com (unknown [10.45.224.2]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 0D4C01954105 for ; Wed, 3 Dec 2025 18:25:12 +0000 (UTC) From: Paolo Abeni To: mptcp@lists.linux.dev Subject: [PATCH mptcp-next] mptcp: cleanup duplicate ack suppression on fastclose. Date: Wed, 3 Dec 2025 19:25:07 +0100 Message-ID: <6d4733b0268246892cbbb8c2d3bcebce1714404a.1764786299.git.pabeni@redhat.com> Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 7NwQiCDnCBC2saNDRnAfpNdhVFDuTSOqAlvAK1FjIQE_1764786314 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8"; x-default="true" The current transition to TCP_CLOSE in __mptcp_close_ssk() is rather obscure, especially since it's done unconditionally for all subflow. Such action is needed only when disposing the given socket - that is for MPJ subflows, or at mptcp close time. Move the statement in a better place and explain it's role for future memory. Signed-off-by: Paolo Abeni --- net/mptcp/protocol.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index cd5a19ab3ba1..61066eb81412 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2533,9 +2533,6 @@ static void __mptcp_close_ssk(struct sock *sk, struct= sock *ssk, if (dispose_it) list_del(&subflow->node); =20 - if (subflow->send_fastclose && ssk->sk_state !=3D TCP_CLOSE) - tcp_set_state(ssk, TCP_CLOSE); - need_push =3D (flags & MPTCP_CF_PUSH) && __mptcp_retransmit_pending_data(= sk); if (!dispose_it) { __mptcp_subflow_disconnect(ssk, subflow, flags); @@ -2554,6 +2551,10 @@ static void __mptcp_close_ssk(struct sock *sk, struc= t sock *ssk, WARN_ON_ONCE(!sock_flag(ssk, SOCK_DEAD)); kfree_rcu(subflow, rcu); } else { + /* Prevent __tcp_close() from sending additional resets */ + if (subflow->send_fastclose && ssk->sk_state !=3D TCP_CLOSE) + tcp_set_state(ssk, TCP_CLOSE); + /* otherwise tcp will dispose of the ssk and subflow ctx */ __tcp_close(ssk, 0); =20 --=20 2.52.0