From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753378Ab2GWBnE (ORCPT ); Sun, 22 Jul 2012 21:43:04 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:54241 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753322Ab2GWBnA (ORCPT ); Sun, 22 Jul 2012 21:43:00 -0400 Message-Id: <20120723010703.011762368@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 23 Jul 2012 02:08:07 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, John Stultz , Richard Cochran , Thomas Gleixner , Prarit Bhargava , John Stultz Subject: [ 076/108] timekeeping: Fix CLOCK_MONOTONIC inconsistency during leapsecond In-Reply-To: <20120723010651.408577075@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: John Stultz This is a backport of fad0c66c4bb836d57a5f125ecd38bed653ca863a which resolves a bug the previous commit. Commit 6b43ae8a61 (ntp: Fix leap-second hrtimer livelock) broke the leapsecond update of CLOCK_MONOTONIC. The missing leapsecond update to wall_to_monotonic causes discontinuities in CLOCK_MONOTONIC. Adjust wall_to_monotonic when NTP inserted a leapsecond. Reported-by: Richard Cochran Signed-off-by: John Stultz Tested-by: Richard Cochran Link: http://lkml.kernel.org/r/1338400497-12420-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner Cc: Prarit Bhargava Cc: Thomas Gleixner Cc: Linux Kernel Signed-off-by: John Stultz Signed-off-by: Ben Hutchings --- kernel/time/timekeeping.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 4780a7d..5c9b67e 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -938,6 +938,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift) xtime.tv_sec++; leap = second_overflow(xtime.tv_sec); xtime.tv_sec += leap; + wall_to_monotonic.tv_sec -= leap; } /* Accumulate raw time */ @@ -1048,7 +1049,7 @@ static void update_wall_time(void) xtime.tv_sec++; leap = second_overflow(xtime.tv_sec); xtime.tv_sec += leap; - + wall_to_monotonic.tv_sec -= leap; } /* check to see if there is a new clocksource to use */