Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754681AbZAFT5N (ORCPT ); Tue, 6 Jan 2009 14:57:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751767AbZAFT5D (ORCPT ); Tue, 6 Jan 2009 14:57:03 -0500 Received: from bsdimp.com ([199.45.160.85]:64343 "EHLO harmony.bsdimp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751705AbZAFT5B (ORCPT ); Tue, 6 Jan 2009 14:57:01 -0500 X-Greylist: delayed 406 seconds by postgrey-1.27 at vger.kernel.org; Tue, 06 Jan 2009 14:57:00 EST Date: Tue, 06 Jan 2009 12:40:55 -0700 (MST) Message-Id: <20090106.124055.143671472.imp@bsdimp.com> To: linasvepstas@gmail.com Cc: johnstul.lkml@gmail.com, david@lang.hm, goodgerster@gmail.com, kyle@moffetthome.net, slashdot@jameshallam.info, zippel@linux-m68k.org, davidn@davidnewall.com, linux-kernel@vger.kernel.org, hancockr@shaw.ca, ntpwg@lists.ntp.isc.org, pretzalz@techhouse.org, burdell@iruntheinter.net, nick@nick-andrew.net, jeff@kosowsky.org Subject: Re: [ntpwg] Bug: Status/Summary of slashdot leap-second crash on new years 2008-2009 From: "M. Warner Losh" In-Reply-To: <3ae3aa420901052053m5a410671u13ecccfb7e29260c@mail.gmail.com> References: <3ae3aa420901050942y56f0ecdei39c091a73e49c1fd@mail.gmail.com> <1f1b08da0901051827r57158990ic795208ba37120ad@mail.gmail.com> <3ae3aa420901052053m5a410671u13ecccfb7e29260c@mail.gmail.com> X-Mailer: Mew version 5.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1808 Lines: 40 In message: <3ae3aa420901052053m5a410671u13ecccfb7e29260c@mail.gmail.com> "Linas Vepstas" writes: : 2009/1/5 john stultz-lkml : : > On Mon, Jan 5, 2009 at 9:42 AM, Linas Vepstas wrote: : > [snip] : >> The long term solution would be write an RFC to extend : >> NTP to also provide TAI information -- e.g. to add a : >> message that indicates the current leap-second offset : >> between UTC and TAI. : > : > I believe Roman has already added this ability: : > http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=153b5d054ac2d98ea0d86504884326b6777f683d;hp=9f14f669d18477fe3df071e2fa4da36c00acee8e : : Well, you're answering a different statment than what : I was talking about -- I wanted to make sure that TAI : information was available via NTP -- this has nothing : to do with the kernel, and would be something available : to all operating systems. : : Anyway -- I'm looking at the patch you reference, and : maybe I'm being dumb -- but -- I think I see a bug. : : case TIME_DEL decrements TAI, but TIME_INS does : not increment it. Instead, there's a lonely increment in : TIME_OOP which seems wrong. ?? No. That's right. The increment doesn't happen until the leap second has happened. The TIME_OOP exists to increment the TAI offset at the right time. The decrement would happen right away, since the second is deleted at the end of :58. I had to draw lots of pictures when I was working this code out in FreeBSD. Warner -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/