From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 AC71E2E8DEC; Mon, 17 Aug 2026 15:09:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786979350; cv=none; b=RJ0b6QQuzwhD1hQaOC7WZifsBp24svrSl8w07jkQoPKQxXgehPPQ2PpbomXpZF6VO0qNzVqfYfmGzPVFSYC/IvhfatZA8iDl8YkdX/1VmWhqUg7C9w4wgrAj7MBSXnD2peviG01jO7/Vl5NVMobdpYFnp2l08S/MFg3F0lDTS+0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786979350; c=relaxed/simple; bh=YhV/oQUzIpVFsdK+0WbT8fdPoMR9ShpW78M/4ek6NGo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=FRLR1I6JCb0wXkFJCGFXvxHwzEqydBW2FVyNTcnYMZ3XY0ttgVT4rV+KfpcC+ynXzi7GN4GWs4NpKLXYEoOvmBpLN5GR0GQbbmrWTmXCWn5RM5pXCYn4FW7oHkJb+f2LT/pB1CFU5zcRj4TaRVuee65Fxu79dBNv4yqFolWfCv8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xzIb3C2m; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="xzIb3C2m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7F2E1F000E9; Mon, 17 Aug 2026 15:09:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786979349; bh=1RBFBNE6h5EOltC3POvCmO/vEuObF48eK9Gv0ZX+rf4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=xzIb3C2mWed89QRsh/VeFAg1jaOTWG7totNPwqqGAmmeUAFV0MsrskrROFxYM8Hdg 0+qjjspDYCUje+aP5NuySpa9XSKLfA+GS5CNNbA/aCjr9ftma7MCpkbbdZ8iVPheS2 NYziKH4ORGkt6JHrZ9vL0LHzR15fRYUPC+Lkbzxs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qingfang Deng , =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 157/609] ppp: use IFF_NO_QUEUE in virtual interfaces Date: Mon, 17 Aug 2026 15:27:33 +0200 Message-ID: <20260817132549.264642133@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132543.039278408@linuxfoundation.org> References: <20260817132543.039278408@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Qingfang Deng [ Upstream commit 95d0d094ba26432ec467e2260f4bf553053f1f8f ] For PPPoE, PPTP, and PPPoL2TP, the start_xmit() function directly forwards packets to the underlying network stack and never returns anything other than 1. So these interfaces do not require a qdisc, and the IFF_NO_QUEUE flag should be set. Introduces a direct_xmit flag in struct ppp_channel to indicate when IFF_NO_QUEUE should be applied. The flag is set in ppp_connect_channel() for relevant protocols. While at it, remove the usused latency member from struct ppp_channel. Signed-off-by: Qingfang Deng Reviewed-by: Toke Høiland-Jørgensen Link: https://patch.msgid.link/20250301135517.695809-1-dqfext@gmail.com Signed-off-by: Jakub Kicinski Stable-dep-of: 543adf072165 ("ppp: annotate data races in ppp_generic") Signed-off-by: Sasha Levin --- drivers/net/ppp/ppp_generic.c | 4 ++++ drivers/net/ppp/pppoe.c | 1 + drivers/net/ppp/pptp.c | 1 + include/linux/ppp_channel.h | 3 +-- net/l2tp/l2tp_ppp.c | 1 + 5 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index d3ea1d6da20568..5d0cde253683d6 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -3508,6 +3508,10 @@ ppp_connect_channel(struct channel *pch, int unit) ret = -ENOTCONN; goto outl; } + if (pch->chan->direct_xmit) + ppp->dev->priv_flags |= IFF_NO_QUEUE; + else + ppp->dev->priv_flags &= ~IFF_NO_QUEUE; spin_unlock_bh(&pch->downl); if (pch->file.hdrlen > ppp->file.hdrlen) ppp->file.hdrlen = pch->file.hdrlen; diff --git a/drivers/net/ppp/pppoe.c b/drivers/net/ppp/pppoe.c index 1744a3e3ae2cf7..6a1c1e1916698c 100644 --- a/drivers/net/ppp/pppoe.c +++ b/drivers/net/ppp/pppoe.c @@ -699,6 +699,7 @@ static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr, po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr) - 2; po->chan.private = sk; po->chan.ops = &pppoe_chan_ops; + po->chan.direct_xmit = true; error = ppp_register_net_channel(dev_net(dev), &po->chan); if (error) { diff --git a/drivers/net/ppp/pptp.c b/drivers/net/ppp/pptp.c index bf011bbb610589..466dd4575f9983 100644 --- a/drivers/net/ppp/pptp.c +++ b/drivers/net/ppp/pptp.c @@ -469,6 +469,7 @@ static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr, po->chan.mtu -= PPTP_HEADER_OVERHEAD; po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header); + po->chan.direct_xmit = true; error = ppp_register_channel(&po->chan); if (error) { pr_err("PPTP: failed to register PPP channel (%d)\n", error); diff --git a/include/linux/ppp_channel.h b/include/linux/ppp_channel.h index 45e6e427ceb8a0..f73fbea0dbc239 100644 --- a/include/linux/ppp_channel.h +++ b/include/linux/ppp_channel.h @@ -42,8 +42,7 @@ struct ppp_channel { int hdrlen; /* amount of headroom channel needs */ void *ppp; /* opaque to channel */ int speed; /* transfer rate (bytes/second) */ - /* the following is not used at present */ - int latency; /* overhead time in milliseconds */ + bool direct_xmit; /* no qdisc, xmit directly */ }; #ifdef __KERNEL__ diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c index 34d8582c0c072e..2e856a83a7506b 100644 --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -810,6 +810,7 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, po->chan.private = sk; po->chan.ops = &pppol2tp_chan_ops; po->chan.mtu = pppol2tp_tunnel_mtu(tunnel); + po->chan.direct_xmit = true; error = ppp_register_net_channel(sock_net(sk), &po->chan); if (error) { -- 2.53.0