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 40AEFC433EF for ; Wed, 29 Dec 2021 20:15:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231818AbhL2UPj (ORCPT ); Wed, 29 Dec 2021 15:15:39 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:33654 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231773AbhL2UPj (ORCPT ); Wed, 29 Dec 2021 15:15:39 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id F3DB9614D9; Wed, 29 Dec 2021 20:15:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00303C36AEA; Wed, 29 Dec 2021 20:15:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1640808938; bh=7iyaFWLPgYjnHDSKKvd0Mh8/pRpkgZcI8x6NKYB2mnU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=WX82uNED7rbYUY9uxhIffcoGboMiIvqurlmdOLXYH+QmXSA6PIIUQ3LPeXjUgn7SW 6CmL7+ZSc3Jcx5nzEsFuqF30IMMQ/WYHRiJPznqfwAQsxYvxr6AaA9u9ODXtpKCYzr j25LGAsMyo/UBdu2lN/uOTFSS6fBPHOwU0AbmUKvYuJdTIPTlC9j2L4RHA3/4uDfth hNTiizJA4l/3iVj9/oCnWDTvRtLN0JIUi2RYD20YTM43TQusv033n1cWnVVXBcc5h8 0a84MFo09GzI7KT4aTz8P2sdsOzqLFDYX43mw1Y2hgssFuFCY6sZpUYzFfpqBt+Qa7 8ts7LjuJOAU7w== Date: Wed, 29 Dec 2021 12:15:36 -0800 From: Jakub Kicinski To: cgel.zte@gmail.com Cc: davem@davemloft.net, corbet@lwn.net, netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, xu xin , Zeal Robot Subject: Re: [PATCH linux-next] Documentation: fix outdated interpretation of ip_no_pmtu_disc Message-ID: <20211229121536.06d270e5@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> In-Reply-To: <20211229031245.582451-1-xu.xin16@zte.com.cn> References: <20211229031245.582451-1-xu.xin16@zte.com.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Wed, 29 Dec 2021 03:12:45 +0000 cgel.zte@gmail.com wrote: > From: xu xin > > The updating way of pmtu has changed, but documentation is still in the > old way. See commit-id 28d35bcdd3925e7293408cdb8aa5f2aac5f0d6e3. So This not a correct way to quote a commit, please use: %h (\"%s\") as the format. > patch fix interpretation of ip_no_pmtu_disc. > > Besides, min_pmtu seems not to be discoverd, but set. > > Reported-by: Zeal Robot How does the bot discover this sort of problem? > 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 I don't see how this is a meaningful distinction to someone reading this documentation, more of a corner case. > + 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. Use tabs instead of spaces. > 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 Also not must of an improvement IMHO. > ip_forward_use_pmtu - BOOLEAN > By default we don't trust protocol path MTUs while forwarding