How to debug hard lockup issue

[Lin Ming]

Hi list,

I encountered a hard lockup on a armv5 board with 2.6.32 kernel.
There is no any message output since it is hard lockup.

I tried watchdog, but watchdog can only reset the board. I still can't
get any info.

The hard lockup is possibly because kernel blocked/looped with
interrupts disabled.

Is there any non-maskable interrupt I can use to dump the kernel stack?
Or any other hint?

Thanks,
Lin Ming