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Date: Mon, 4 Aug 2003 23:49:22 +0200 (CEST)
From: Tim Schmielau <tim@physik3.uni-rostock.de>
To: Patrick Moor <pmoor@netpeople.ch>
cc: lkml <linux-kernel@vger.kernel.org>, george anzinger <george@mvista.com>
Subject: Re: time jumps (again)
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> Some days ago I started noticing strange time jumps on my Athlon system.
> (Asus board, VIA chipset, AMD Athlon 650MHz processor). I haven't
> noticed them before and I am pretty sure there weren't any for the last
> few years! Uptime of the machine is now 218 days, and problems began
> appearing after 215 days approximately.
>
> What happens: when doing a
>   $ while true; do date; done
> I'm noticing time jumps _exactly_ at the beginning of a "new" second (or
> at the end of an "old" one). the jump is exactly 4294 (4295) seconds
> into the future. Example:
> ...
> Mon Aug  4 18:11:06 CEST 2003
> Mon Aug  4 18:11:06 CEST 2003
> Mon Aug  4 19:22:41 CEST 2003
> Mon Aug  4 19:22:41 CEST 2003
> Mon Aug  4 19:22:41 CEST 2003
> Mon Aug  4 18:11:07 CEST 2003
> Mon Aug  4 18:11:07 CEST 2003
> ...
>

Wild guess - does the following patch fix it?

Tim


--- linux-2.4.20/arch/i386/kernel/time.c.orig	Mon Aug  4 23:38:47 2003
+++ linux-2.4.20/arch/i386/kernel/time.c	Mon Aug  4 23:40:53 2003
@@ -274,8 +274,8 @@
 	read_lock_irqsave(&xtime_lock, flags);
 	usec = do_gettimeoffset();
 	{
-		unsigned long lost = jiffies - wall_jiffies;
-		if (lost)
+		long lost = jiffies - wall_jiffies;
+		if (lost>0)
 			usec += lost * (1000000 / HZ);
 	}
 	sec = xtime.tv_sec;