In article <200102220002.f1M02uD22892@buzzard.freeserve.co.uk>,
   Richard Earnshaw <rearnsha@buzzard.freeserve.co.uk> wrote:
> re you sure this was "on entry"?  I can't find that message in the source.

Yes. I have tried it again and it definitely says 'on entry' as
well as 'on exit'. 

Now that I know that the problem is recoverable, I have some
extra information. I tried running the ktrace command as you
suggested. I got matched pairs of 'spl level=6 on entry' and
'spl level=6 on exit' on the console from which I was trying
to run X and on root. On root there were twelve pairs of
messages, 'entry' first and then 'exit'. There was also the
traditional 'Multiple open of /dev/vidcvideo0 by proc 204'
message that always seems to show up with Xarm32VIDC.

> > Stopped in Xarm32VIDC at _cpu_Debugger+0x10: ldmdb r11,{r11,r13,r15}
> > 
> > The messages above were repeated a number of times. (About 10, I
> > think.) After that I got the db> prompt but it would not take any
> > more input. I found that the machine was working normally again
> > when I switched to one of the other consoles. I found that there
> > is a core dump (Xarm32VIDC.core). This is the first time this has
> > been produced.
> > 

> So, we have a syscall that is trying to return control to the user without 
> resetting the interrupt levels.  naughty!  A ktrace should tell us what it 
> is, and how it fails.

> R.

I ran the ktrace trace with:

  ktrace -d xinit

Would this have produced the output you want? A ktrace.out file
has been produced; it is a little over 200K bytes long. If I have
run the trace correctly I will email it to you, if you want to
examine it.

Dave Daniels