Re: Catching NForce2 lockup with NMI watchdog

[Josh McKinney]

On approximately Fri, Dec 05, 2003 at 08:40:58AM +0100, Mikael Pettersson wrote:
> Jesse Allen writes:
>  > Hi,
>  > 
>  > I have a NForce2 board and can easily reproduce a lockup with grep on an IDE 
>  > hard disk at UDMA 100.  The lockup occurs when both Local APIC + IO-APIC are 
>  > enabled.  It was suggested to me to use NMI watchdog to catch it.  However, the 
>  > NMI watchdog doesn't seem to work.
>  > 
>  > When I set the kernel parameter "nmi_watchdog=1" I get this message in 
>  > /var/log/syslog:
>  > Dec  4 20:10:30 tesore kernel: ..MP-BIOS bug: 8254 timer not connected to 
>  > IO-APIC
>  > Dec  4 20:10:30 tesore kernel: timer doesn't work through the IO-APIC - 
>  > disabling NMI Watchdog!
>  > 
>  > "nmi_watchdog=2" seems to work at first, In /var/log/messages:
>  > Dec  4 20:13:11 tesore kernel: testing NMI watchdog ... OK.
>  > but it still locks up.
> 
> The NMI watchdog can only handle software lockups, since it relies on
> the CPU, and for nmi_watchdog=1 the I/O-APIC + bus, still running.
> Hardware lockups result in, well, hardware lockups :-(

So does this confirm that the lockups with nforce2 chipsets and apic
is actually a hardware problem after all? 
  
-- 
Josh McKinney		     |	Webmaster: http://joshandangie.org
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