Re: Back to the Future ? or some thing sinister ?

[Nathan Lynch <ntl@pobox.com>]

Chaitanya Hazarey wrote:
>
> We have got a machine, lets say X , make is IBM and the CPU is Intel
> Pentium 4 2.60 GHz. Its running a 2.6.13.1 Kernel and previously,
> 2.6.27-4 Kernel the distribution is Debian Sagre.
> 
> processor       : 0
> vendor_id       : GenuineIntel
> cpu family      : 15
> model           : 2
> model name      : Intel(R) Pentium(R) 4 CPU 2.60GHz
> stepping        : 9
> cpu MHz         : 2591.888
> cache size      : 512 KB
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 2
> wp              : yes
> flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid
> xtpr
> bogomips        : 5188.79
> 
> 
> 
> 
> The problem is that, after a some time ( fuzzy , but I think like 2
> hours ) of inactivity or because of some esoteric factor which triggers
> a state in which the time on the machine starts going around in a loop.
> if I do cat /proc/uptime, it goes 4  ticks ahead and again rewinds back
> to the starting count ( not zero, but the moment in time when the event
> was triggred. )
> 
> The problem seems to be specific to the 2.6 series of kernel, not the
> 2.4 series.
> 
> I  would like to know how to go about the debugging of the problem, and
> that which specific part of the kernel will be directly interacting with
> the rtc / system clock.

Look into upgrading the BIOS on that machine; I've had similar
problems on a IBM P4 workstation that were fixed in this way.