From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755616AbbFLPAR (ORCPT ); Fri, 12 Jun 2015 11:00:17 -0400 Received: from arcturus.aphlor.org ([188.246.204.175]:39772 "EHLO arcturus.aphlor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755251AbbFLPAP (ORCPT ); Fri, 12 Jun 2015 11:00:15 -0400 Date: Fri, 12 Jun 2015 10:59:59 -0400 From: Dave Jones To: Prarit Bhargava Cc: John Stultz , linux-kernel@vger.kernel.org, Daniel Bristot de Oliveira , Richard Cochran , Jan Kara , Jiri Bohac , Thomas Gleixner , Ingo Molnar , Shuah Khan Subject: Re: [PATCH 0/5 v2] Fixes for leapsecond expiring early ABS_TIME CLOCK_REALTIME timers Message-ID: <20150612145958.GB22489@codemonkey.org.uk> Mail-Followup-To: Dave Jones , Prarit Bhargava , John Stultz , linux-kernel@vger.kernel.org, Daniel Bristot de Oliveira , Richard Cochran , Jan Kara , Jiri Bohac , Thomas Gleixner , Ingo Molnar , Shuah Khan References: <1434063297-28657-1-git-send-email-john.stultz@linaro.org> <20150612145211.GA22489@codemonkey.org.uk> <557AF2FD.2070606@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <557AF2FD.2070606@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Score: -2.9 (--) X-Spam-Report: Spam report generated by SpamAssassin on "arcturus.aphlor.org" Content analysis details: (-2.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-Authenticated-User: davej@codemonkey.org.uk Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 12, 2015 at 10:55:57AM -0400, Prarit Bhargava wrote: > > > This series has only had limited testing, so I wanted to send > > > it out for initial review and comment. Folks can grab this tree > > > via git for testing here: > > > https://git.linaro.org/people/john.stultz/linux.git dev/early-leap-timer > > > > Any idea how far back this reaches ? Ie, which longterm stable releases > > might be affected by this ? > > Likely occurs in any kernel after NOHZ was introduced. At least on 3.14, it seems to happen even if NOHZ is disabled. # ./leap -i 5 -s Setting time to speed up testing Running for 5 iterations. Press ctrl-c to stop Setting time to Sat Jun 13 23:59:50 2015 Scheduling leap second for Sun Jun 14 00:00:00 2015 Setting timer for Sun Jun 14 00:00:00 2015 Sat Jun 13 23:59:57 2015 + 55 us (1) TIME_INS Sat Jun 13 23:59:57 2015 + 500127 us (1) TIME_INS Sat Jun 13 23:59:58 2015 + 189 us (1) TIME_INS Sat Jun 13 23:59:58 2015 + 500250 us (1) TIME_INS Sat Jun 13 23:59:59 2015 + 312 us (1) TIME_INS Sat Jun 13 23:59:59 2015 + 500372 us (1) TIME_INS Sun Jun 14 00:00:00 2015 + 3 us (1) TIME_INS - TIMER FIRED Error: Incorrect NTP state? Sun Jun 14 00:00:00 2015 + 12 us (1) TIME_INS Sat Jun 13 23:59:59 2015 + 500068 us (2) TIME_OOP Sun Jun 14 00:00:00 2015 + 130 us (2) TIME_OOP Sun Jun 14 00:00:00 2015 + 500190 us (2) TIME_WAIT Sun Jun 14 00:00:01 2015 + 256 us (2) TIME_WAIT Sun Jun 14 00:00:01 2015 + 500315 us (2) TIME_WAIT Sun Jun 14 00:00:02 2015 + 376 us (2) TIME_WAIT Leap complete Errors observed Dave