From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5C73C433EF for ; Wed, 29 Dec 2021 03:12:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238480AbhL2DMx (ORCPT ); Tue, 28 Dec 2021 22:12:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232913AbhL2DMx (ORCPT ); Tue, 28 Dec 2021 22:12:53 -0500 Received: from mail-qt1-x830.google.com (mail-qt1-x830.google.com [IPv6:2607:f8b0:4864:20::830]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3F6D7C061574; Tue, 28 Dec 2021 19:12:53 -0800 (PST) Received: by mail-qt1-x830.google.com with SMTP id j17so17830157qtx.2; Tue, 28 Dec 2021 19:12:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=CWajVAM/CofGIyu/UgB14ELKgBM5UfoqrcGTS6HVdrw=; b=M0HYVdM1LB1ODR6IbUkd6r9SdSXTBTIVXhtAwWk/Ps/PNBQK3KHWoJ3rNvIKlJ5vp+ l2dYHqPYFxLKfYfxvWD8/gfXUl2xCwPLFkmvGcNwMgEVCsVclGKdsgOBTthJn7jpvz94 l27Yeba35g7gQtwbkfhR09ucZkKE+WKdJVQQSbHaSFMhWrXE9mzUpeKEbJyrL9T8iy4L 9kNfDSoXF6NWdXgMD6M5kaXhrbu0vB8Tgv5gzMDhSGT8+kPfYtZQreLfRij3zw72eZlh HOEL+LyvhrpAKp2WofrK0Pd0au5g8JgtjbRRuPKBynOZ5CkVUMbUT3rVlSZY5yP2ajRh BXwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=CWajVAM/CofGIyu/UgB14ELKgBM5UfoqrcGTS6HVdrw=; b=wg+x83V2bQiRtwESQ6nyfZt+Jr7MbegHj36WDpO9V5UGBoBTtyuuFkAEgja1aR6hn/ KUN3d9kiDyDo+ZugAfOVdxpJEur1gh7kGB7+lJMaau4L6DfVz+KfyaeqYs3rgNB5issh 6S8J7mxJbC5jhMkmSTSuNo4FGHChLoWaNo0BjhWmB1kXQIJ2Up7ZApxkq7KoSU9DwRPm NoIDLjOsPeZ3lw9AVxoYgcktytpdrSBJ9V/HzLfnfgGjlCOsxvFhNthn6v8wP7olFcSX CLoKtKnLb6HgSKQ+afegOLOz3CKugz6SwovwYQSiA7Ux7/Cd9L8d4yQgwF9j3dy+ICzC rRJA== X-Gm-Message-State: AOAM530GmOLCmH/u9g7X6loMsoNA82a6ue7WixU9AIaIH/6DcqJ8Yr2R NoDJaJhFLioDkgMQR2s1qow= X-Google-Smtp-Source: ABdhPJyEjdm/+u2HjWz7v0WCSc3hGEIARUz4YKJ55KY0OnWjnRy8tfYmyj4eiVAB8bq8OCpoUqvbKA== X-Received: by 2002:a05:622a:14d0:: with SMTP id u16mr21354453qtx.641.1640747572450; Tue, 28 Dec 2021 19:12:52 -0800 (PST) Received: from localhost.localdomain ([193.203.214.57]) by smtp.gmail.com with ESMTPSA id t15sm17739972qta.45.2021.12.28.19.12.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Dec 2021 19:12:51 -0800 (PST) From: cgel.zte@gmail.com X-Google-Original-From: xu.xin16@zte.com.cn To: davem@davemloft.net Cc: kuba@kernel.org, corbet@lwn.net, netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, xu xin , Zeal Robot Subject: [PATCH linux-next] Documentation: fix outdated interpretation of ip_no_pmtu_disc Date: Wed, 29 Dec 2021 03:12:45 +0000 Message-Id: <20211229031245.582451-1-xu.xin16@zte.com.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org From: xu xin The updating way of pmtu has changed, but documentation is still in the old way. See commit-id 28d35bcdd3925e7293408cdb8aa5f2aac5f0d6e3. So This patch fix interpretation of ip_no_pmtu_disc. Besides, min_pmtu seems not to be discoverd, but set. Reported-by: Zeal Robot Signed-off-by: xu xin --- Documentation/networking/ip-sysctl.rst | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index c04431144f7a..dd5e53318805 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -25,9 +25,11 @@ ip_default_ttl - INTEGER ip_no_pmtu_disc - INTEGER Disable Path MTU Discovery. If enabled in mode 1 and a fragmentation-required ICMP is received, the PMTU to this - destination will be set to min_pmtu (see below). You will need - to raise min_pmtu to the smallest interface MTU on your system - manually if you want to avoid locally generated fragments. + destination will be set to the smallest of the old MTU + and ip_rt_min_pmtu (see __ip_rt_update_pmtu() in + net/ipv4/route.c). You will need to raise min_pmtu to the + smallest interface MTU on your system manually if you want to + avoid locally generated fragments. In mode 2 incoming Path MTU Discovery messages will be discarded. Outgoing frames are handled the same as in mode 1, @@ -49,7 +51,7 @@ ip_no_pmtu_disc - INTEGER Default: FALSE min_pmtu - INTEGER - default 552 - minimum discovered Path MTU + default 552 - minimum set Path MTU ip_forward_use_pmtu - BOOLEAN By default we don't trust protocol path MTUs while forwarding -- 2.25.1