total hang

[Keith Owens]

On Tue, 21 Aug 2001 11:35:48 -0400, 
Kapish K <kapish at ureach.com> wrote:
>      We see a wierd situation here - when we run some tests on
>an smp system, we see a total system freeze... whats'
>interesting is that we turn on magic-sysrq and kdb, but still we
>are totally locked on the keyboard - can't get to kdb or make
>the magic-sysrq work.. is there any other hacks to get into the
>system one way or the other and get some info.? network doesn't
>work either - no ping packets..

Sounds like a disabled spin loop, interrupts are being ignored.  Use
the non maskable interrupt, see Documentation/nmi_watchdog.txt.