From 70a062286b9dfcbd24d2e11601aecfead5cf709a Mon Sep 17 00:00:00 2001 From: Tim Deegan Date: Thu, 10 Feb 2011 08:50:41 +0000 Subject: [PATCH] fix jiffy calculations in calibrate_delay_direct to handle overflow 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 Cc: stable@kernel.org Signed-off-by: Linus Torvalds --- init/calibrate.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/init/calibrate.c b/init/calibrate.c index 6eb48e53d61c..24fe022c55f9 100644 --- a/init/calibrate.c +++ b/init/calibrate.c @@ -66,7 +66,7 @@ static unsigned long __cpuinit calibrate_delay_direct(void) 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_delay_direct(void) 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); } -- 2.20.1