Could somebody please give me a lesson on this area.

I get the following messages during booting:

  Digital Personal WorkStation 600au, 598MHz
  8192 byte page size, 1 processor.
  real mem = 134217728 (1933312 reserved for PROM, 132284416 used by NetBSD)
  avail mem = 113229824
  using 1614 buffers containing 13221888 bytes of memory
  mainbus0 (root)
  cpu0 at mainbus0: ID 0 (primary), 21164A ()
  cia0 at mainbus0: DECchip 2117x Core Logic Chipset (Pyxis), pass 1
  cia0: extended capabilities: 1<BWEN>
  cia0: using BWX for PCI config access
  sio_intr_setup: 1 LT!
  sio_sis: initial: ocw = (a3,ff), elcr = ( 2,14)
           current: ocw = (a3,ff), elcr = ( 0,14)
  panic: sio_setirqstat: hosed

I have two similar machines that don't have this problem.  They each 
have a slightly different configuration.

I took a quick look at the code.  I think this has something to do 
with edge triggered vs level triggered interrupts.  I'm guessing 
that some board in this system is in a slot that's wired to the wrong 
kind of interrupt. 

Is there any simple way to figure out which board is causing the 
problem and/or what configurations will or won't work?