Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753505Ab3GXOSL (ORCPT ); Wed, 24 Jul 2013 10:18:11 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:45888 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751138Ab3GXOGr (ORCPT ); Wed, 24 Jul 2013 10:06:47 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Arjan van de Ven" , "Bart Van Assche" , "Thomas Gleixner" , "Stephen Rothwell" , "Bart Van Assche" Date: Wed, 24 Jul 2013 15:02:45 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [51/85] timer: Fix jiffies wrap behavior of round_jiffies_common() In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.101 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 Content-Length: 1390 Lines: 44 3.2.49-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche commit 9e04d3804d3ac97d8c03a41d78d0f0674b5d01e1 upstream. Direct compare of jiffies related values does not work in the wrap around case. Replace it with time_is_after_jiffies(). Signed-off-by: Bart Van Assche Cc: Arjan van de Ven Cc: Stephen Rothwell Link: http://lkml.kernel.org/r/519BC066.5080600@acm.org Signed-off-by: Thomas Gleixner Signed-off-by: Ben Hutchings --- kernel/timer.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/kernel/timer.c +++ b/kernel/timer.c @@ -145,9 +145,11 @@ static unsigned long round_jiffies_commo /* now that we have rounded, subtract the extra skew again */ j -= cpu * 3; - if (j <= jiffies) /* rounding ate our timeout entirely; */ - return original; - return j; + /* + * Make sure j is still in the future. Otherwise return the + * unmodified value. + */ + return time_is_after_jiffies(j) ? j : original; } /** -- 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/