From owner-freebsd-transport@freebsd.org Thu Aug 25 17:56:31 2016 Return-Path: Delivered-To: freebsd-transport@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B72D0BC6EC1 for ; Thu, 25 Aug 2016 17:56:31 +0000 (UTC) (envelope-from kbowling@llnw.com) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 99C731BDF for ; Thu, 25 Aug 2016 17:56:31 +0000 (UTC) (envelope-from kbowling@llnw.com) Received: by mailman.ysv.freebsd.org (Postfix) id 98EEDBC6EBF; Thu, 25 Aug 2016 17:56:31 +0000 (UTC) Delivered-To: transport@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 987F4BC6EBE for ; Thu, 25 Aug 2016 17:56:31 +0000 (UTC) (envelope-from kbowling@llnw.com) Received: from mail-yw0-x22c.google.com (mail-yw0-x22c.google.com [IPv6:2607:f8b0:4002:c05::22c]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 64CED1BDE for ; Thu, 25 Aug 2016 17:56:31 +0000 (UTC) (envelope-from kbowling@llnw.com) Received: by mail-yw0-x22c.google.com with SMTP id r9so34246291ywg.0 for ; Thu, 25 Aug 2016 10:56:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=llnw.com; s=google; h=mime-version:from:date:message-id:subject:to; bh=9uA10qdLEDJszgbKb/uXIbVpFAzUFviI6J/pl4h5FyQ=; b=QmsQNuv+oXz+BrX4fLfJufsBDdjZ7GpkzSdWrpKIjzOOiLoL+DLGMlL+6al5CxbQaY 5RLwT/4HeTFK0PtGj6ZueVTn+UfnHXa/8n0/0eDgxnzuDOiB9IcuzcOFLGf2eGAZEQJS w9hIHXW0JSHz1LKUZusXWNKTxpzyqfphyhcoQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=9uA10qdLEDJszgbKb/uXIbVpFAzUFviI6J/pl4h5FyQ=; b=VHIkwNf/UJsOMatB/yPnP0QrqJicPm4siVaXg8l2qs+xyT8tm1KRevQ7JL54/2W0bD odjHbnes4v89XvP1YZl+eT/lfjqE3b2mJJZaDvlVguwvsHpGmBz2AlnQhPWMRFxG4EAp uMVrHUvg2EklOiqdebHRKf/JmSA0LP4ypBzHx4PNqPj+oVvmp/av5DGN8D9FgfvZZgRP kykKmYFklFgTCrUJKRRqZcilqBZOlGT2i1lrii9bm8vDVYq969VXDR1lz23mhjliomL0 9EM1MhwH/aQ99xHImgeVx8NMDd+iX/gyrMeH1Z5JeKgNkA6S8YARijzBGn7TIQu2VXZr HJGw== X-Gm-Message-State: AE9vXwOa/9Bv9WqpXW+UjUZsjiL6CiTgiyO3mWIxjx5g0qaBHryF43Bc5NvR/w7rJojvMDar/RAstJq05GvpEykwvYrtrYjgSmBvj/2CQ8OtCdZYB83Z7xluk0hylkb1HjDbmo5GTKZ4utEwEg== X-Received: by 10.129.39.8 with SMTP id n8mr7786350ywn.294.1472147790334; Thu, 25 Aug 2016 10:56:30 -0700 (PDT) MIME-Version: 1.0 Received: by 10.37.68.137 with HTTP; Thu, 25 Aug 2016 10:56:29 -0700 (PDT) From: Kevin Bowling Date: Thu, 25 Aug 2016 10:56:29 -0700 Message-ID: Subject: Some transport MFCs to stable/11? To: transport@freebsd.org Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.22 X-BeenThere: freebsd-transport@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Discussions of transport level network protocols in FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Aug 2016 17:56:31 -0000 Hi, I'm tracking a list of things that are interesting that don't have MFC metadata in the commits. Do the following plan to MFC to stable/11, or can I have Hiren bring these back? rrs@ https://reviews.freebsd.org/rS304223 https://reviews.freebsd.org/rS304218 sephe@ https://reviews.freebsd.org/rS303766 https://reviews.freebsd.org/rS303656 gallatin@ https://reviews.freebsd.org/rS303626 Regards, Kevin Bowling - Systems Software Team - P: 480-227-1233 -- The information in this message may be confidential. It is intended solely for the addressee(s). If you are not the intended recipient, any disclosure, copying or distribution of the message, or any action or omission taken by you in reliance on it, is prohibited and may be unlawful. Please immediately contact the sender if you have received this message in error. From owner-freebsd-transport@freebsd.org Thu Aug 25 19:53:08 2016 Return-Path: Delivered-To: freebsd-transport@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 27B4FBC6AC0 for ; Thu, 25 Aug 2016 19:53:08 +0000 (UTC) (envelope-from Cheng.Cui@netapp.com) Received: from mx141.netapp.com (mx141.netapp.com [216.240.21.12]) (using TLSv1.2 with cipher RC4-SHA (128/128 bits)) (Client CN "mx141.netapp.com", Issuer "Symantec Class 3 Secure Server CA - G4" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id DFD3917C9 for ; Thu, 25 Aug 2016 19:53:07 +0000 (UTC) (envelope-from Cheng.Cui@netapp.com) X-IronPort-AV: E=Sophos;i="5.28,577,1464678000"; d="scan'208";a="142381768" Received: from hioexcmbx05-prd.hq.netapp.com ([10.122.105.38]) by mx141-out.netapp.com with ESMTP; 25 Aug 2016 12:52:42 -0700 Received: from HIOEXCMBX03-PRD.hq.netapp.com (10.122.105.36) by hioexcmbx05-prd.hq.netapp.com (10.122.105.38) with Microsoft SMTP Server (TLS) id 15.0.1210.3; Thu, 25 Aug 2016 12:52:42 -0700 Received: from HIOEXCMBX03-PRD.hq.netapp.com ([::1]) by hioexcmbx03-prd.hq.netapp.com ([fe80::a009:cb7a:e519:7347%21]) with mapi id 15.00.1210.000; Thu, 25 Aug 2016 12:52:41 -0700 From: "Cui, Cheng" To: "freebsd-transport@freebsd.org" Subject: question about if a recent Linux patch on window scaling is required in FreeBSD Thread-Topic: question about if a recent Linux patch on window scaling is required in FreeBSD Thread-Index: AQHR/wo9NkI6m8KaqUqM3LcKN+2axw== Date: Thu, 25 Aug 2016 19:52:41 +0000 Message-ID: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.122.56.79] Content-Type: text/plain; charset="iso-8859-1" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Mailman-Approved-At: Thu, 25 Aug 2016 21:06:57 +0000 X-BeenThere: freebsd-transport@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Discussions of transport level network protocols in FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Aug 2016 19:53:08 -0000 Hello everyone, I hope this email could reach you well, because I found related discussions about this topic on window scaling and the case of window shrinking (or retraction or loss of precision). And I try to make this question simple. There is a recent Linux patch at receiver side to round-up advertised window due to precision loss of window scaling. It reaches my attention because the same problem could also happen between a pair of Linux and FreeBSD nodes, and I am not aware of any similar patch in FreeBSD yet. The Linux patch is this: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id= =3D6 07bfbf2d55dd1cfe5368b41c2a81a8c9ccf4723 And I quote some description of the Linux patch below: > If the sender uses up the entire window before it is shrunk, this can > have chaotic effects on the connection. When sending ACKs, > tcp_acceptable_seq() will notice that the window has been shrunk since > tcp_wnd_end() is before tp->snd_nxt, which makes it choose tcp_wnd_end() >as=20 > sequence number. This will fail the receivers checks in tcp_sequence() >however=20 > since it is before it's tp->rcv_wup, making it respond with a dupack. I think the Linux's behavior is right ("ACK-only packets should be sent with the largest in-window sequence number that has ever been sent." ref: https://www.ietf.org/mail-archive/web/tcpm/current/msg10512.html), it actually chooses "tp->snd_una+tp->snd_wnd" (tcp_wnd_end()) instead of tp->snd_nxt, as it thought tp->snd_nxt is out of window, in case of precision loss which made the receiver's advertise-window smaller. But at the=20 other side, if the other side is FreeBSD, I think FreeBSD will also fail the=20 check since "tp->snd_una+tp->snd_wnd" is before it's tp->rcv_nxt, and ignore=20 the sequence number in the packet. I also sent an email to tcpm@ietf.org asking if this Linux patch is RFC 7323=20 (window scaling part) compliant, but I have not get any reply yet. So my question here is: Is there any recent change in FreeBSD to accommodate the=20 Linux behavior ("tp->snd_una+tp->snd_wnd" as sequence number)? If not, do we=20 consider to apply the same way as in the Linux patch? Thanks and apologize in advance if I did not do enough research, --Cheng Cui From owner-freebsd-transport@freebsd.org Fri Aug 26 18:29:23 2016 Return-Path: Delivered-To: freebsd-transport@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id F196AA94574 for ; Fri, 26 Aug 2016 18:29:23 +0000 (UTC) (envelope-from hiren@strugglingcoder.info) Received: from mail.strugglingcoder.info (strugglingcoder.info [104.236.146.68]) by mx1.freebsd.org (Postfix) with ESMTP id E236B296F; Fri, 26 Aug 2016 18:29:23 +0000 (UTC) (envelope-from hiren@strugglingcoder.info) Received: from localhost (unknown [10.1.1.3]) (Authenticated sender: hiren@strugglingcoder.info) by mail.strugglingcoder.info (Postfix) with ESMTPA id 27BDA17E05; Fri, 26 Aug 2016 11:29:17 -0700 (PDT) Date: Fri, 26 Aug 2016 11:29:17 -0700 From: hiren panchasara To: Peter Sewell Cc: "Jonathan T. Looney" , "freebsd-transport@freebsd.org" , Sam Kumar Subject: Re: TCP_HAVERCVDFIN Message-ID: <20160826182917.GP41576@strugglingcoder.info> References: <20160817235158.GE68615@strugglingcoder.info> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="lG9v85r552aFjg4G" Content-Disposition: inline In-Reply-To: <20160817235158.GE68615@strugglingcoder.info> User-Agent: Mutt/1.5.23 (2014-03-12) X-BeenThere: freebsd-transport@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Discussions of transport level network protocols in FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Aug 2016 18:29:24 -0000 --lG9v85r552aFjg4G Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 08/17/16 at 04:51P, hiren panchasara wrote: > Resurrecting this thread. >=20 > https://reviews.freebsd.org/D7475 >=20 > I like this new behavior and it is being tested at NF and LLNW without > any known problems. >=20 > Any strong objection against it other than it _may_ break something? :-) > I don't see us getting a conformance test suite anytime soon so I > suggest we go ahead with this fix without any MFC and see how it goes? https://svnweb.freebsd.org/changeset/base/304855 I've kept MFC period to 1 month. If anyone has a strong opinion against MFCing this change, I won't do it. Cheers, Hiren --lG9v85r552aFjg4G Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQF8BAABCgBmBQJXwIp2XxSAAAAAAC4AKGlzc3Vlci1mcHJAbm90YXRpb25zLm9w ZW5wZ3AuZmlmdGhob3JzZW1hbi5uZXRBNEUyMEZBMUQ4Nzg4RjNGMTdFNjZGMDI4 QjkyNTBFMTU2M0VERkU1AAoJEIuSUOFWPt/lqpwIAIUFdg28Epp7WaR6BsnMkZv2 EuOsyxax0jeZL9fj5Zzj3F7wQcKSQNnE8TdJKc2NI3QEOWvt2a1T8wBYEWQsF0JY 0l7HCvkUAqzqS+tMhutmP1UwXdXgivDFONE4GPOxwrR7HwzIy6u4woFV0tLZ+WNH cb9J9ptr0HQo2mLUBLoOshB6lFu0aT6okT/92RsWU7JBbeWOi8LvwXuIcyuono5P kY41pJLRyM9uV3mHFJoLs3XmqNPmMKXz6kuQBsvmw/cdgie0jrpBwXPXSURxNZb6 2hJ9F/6C4ejBxC26zGnWTOAKSS9C78wO2uapLnDaoGSPDlXsdfhYriUxW5fnPgo= =2AT+ -----END PGP SIGNATURE----- --lG9v85r552aFjg4G--