In message <199806102354.QAA26047@lestat.nas.nasa.gov>, Jason Thorpe writes:
>On Wed, 10 Jun 1998 16:45:45 -0700 (MST) 
> Tim Rightnour <root@garbled.net> wrote:
>
> > fatal user trap:
> > 
> >     trap entry = 0x2 (memory management fault)
> >     a0         = 0xffffffffc8000004
> >     a1         = 0x1
> >     a2         = 0x1
> >     pc         = 0x1200205b0
> >     ra         = 0x12001a8d4
> >     curproc    = 0xfffffe0000229c00
> >         pid = 22188, comm = make
> > 
> > Is this just a really long way of saying "SIGBUS" ?  I got 2 of these (from the
> > same make pid) while compiling current this afternoon.
>
>No... if it had been an error in user space, it would have been SIGSEGV.  But
>the address (a0) is in kernel space.
>
>Let's take a look at what we have here:
>
>	a0 == 0xffffffffc8000004.  That is in K1SEG, i.e. a mapped kernel
>	segment.
>
>	a1 == 1.  That means "access violation".  The address is mapped
>	and valid, but the user is not allowed to access it.  (Makes sense;
>	it's a kernel address :-)
>
>	a2 == 1.  That means "during a store".

ok, how do you interpret the pc address?  is that in user space?
i have no idea yet, but is the kernel mapped while in user space?
if so, could it be the user space trying to do a store in kernel space?

What's the ra value indicate?  

mts.