From: Barry Song <21cnbao@gmail.com>
To: akpm@linux-foundation.org, davem@davemloft.net, patrick.ohly@intel.com
Cc: uclinux-dist-devel@blackfin.uclinux.org,
linux-kernel@vger.kernel.org, Barry Song <21cnbao@gmail.com>
Subject: [PATCH] Fix half-Y2K38 problem in timecompare_update while calculating offset
Date: Mon, 28 Sep 2009 18:16:44 +0800 [thread overview]
Message-ID: <1254133004-24877-1-git-send-email-21cnbao@gmail.com> (raw)
ktime will overflow from 03:14:07 UTC on Tuesday, 19 January 2038,
ktime_add() in timecompare_update() will overflow a half earlier.
As a result, wrong offset will be gotten, then cause some strange
problems.
---
kernel/time/timecompare.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/kernel/time/timecompare.c b/kernel/time/timecompare.c
index 71e7f1a..d2d893e 100644
--- a/kernel/time/timecompare.c
+++ b/kernel/time/timecompare.c
@@ -89,7 +89,7 @@ int timecompare_offset(struct timecompare *sync,
* source time
*/
sample.offset =
- ktime_to_ns(ktime_add(end, start)) / 2 -
+ (ktime_to_ns(end) + ktime_to_ns(start)) / 2 -
ts;
/* simple insertion sort based on duration */
--
1.5.6.3
next reply other threads:[~2009-09-28 10:17 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-28 10:16 Barry Song [this message]
2009-09-30 2:44 ` Mike Frysinger
2010-01-05 19:28 ` Mike Frysinger
2010-01-06 3:18 ` Barry Song
2009-09-30 5:35 ` Américo Wang
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