From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756965Ab1DYUYf (ORCPT ); Mon, 25 Apr 2011 16:24:35 -0400 Received: from 1wt.eu ([62.212.114.60]:34062 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932139Ab1DYUYY (ORCPT ); Mon, 25 Apr 2011 16:24:24 -0400 Message-Id: <20110425200233.905313677@pcw.home.local> User-Agent: quilt/0.48-1 Date: Mon, 25 Apr 2011 22:02:53 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@kernel.org, stable-review@kernel.org Cc: Tim Deegan , Jan Beulich , Jiri Slaby , Jeremy Fitzhardinge , Linus Torvalds , Greg Kroah-Hartman Subject: [PATCH 021/173] fix jiffy calculations in calibrate_delay_direct to handle overflow In-Reply-To: <46075c3a3ef08be6d70339617d6afc98@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27.59-stable review patch. If anyone has any objections, please let us know. ------------------ From: Tim Deegan commit 70a062286b9dfcbd24d2e11601aecfead5cf709a upstream. Fixes a hang when booting as dom0 under Xen, when jiffies can be quite large by the time the kernel init gets this far. Signed-off-by: Tim Deegan [jbeulich@novell.com: !time_after() -> time_before_eq() as suggested by Jiri Slaby] Signed-off-by: Jan Beulich Cc: Jiri Slaby Cc: Jeremy Fitzhardinge Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- init/calibrate.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/init/calibrate.c +++ b/init/calibrate.c @@ -66,7 +66,7 @@ static unsigned long __cpuinit calibrate pre_start = 0; read_current_timer(&start); start_jiffies = jiffies; - while (jiffies <= (start_jiffies + 1)) { + while (time_before_eq(jiffies, start_jiffies + 1)) { pre_start = start; read_current_timer(&start); } @@ -74,8 +74,8 @@ static unsigned long __cpuinit calibrate pre_end = 0; end = post_start; - while (jiffies <= - (start_jiffies + 1 + DELAY_CALIBRATION_TICKS)) { + while (time_before_eq(jiffies, start_jiffies + 1 + + DELAY_CALIBRATION_TICKS)) { pre_end = end; read_current_timer(&end); }