> Then I hit C-M-<Esc> and the debugger starts. When I 
> type `trace', I get "bad frame pointer". (I booted netbsd.gdb). 
> Sometimes the debugger crashes and the system restarts (sync
> or kgdb). 

Some additional information: If I make some steps forward in the
debugger (next), then the system hangs again in

  ipw_intr+0x1f3: ret

Invoking the debugger again results in

  kernel: supervisor trap page fault, code=0

Christoph Bauer