[parisc-linux] Re: Trace/Breakpoint trap on "make mrproper"

John Marvin jsm@udlkern.fc.hp.com
Fri, 7 Sep 2001 07:56:42 -0600 (MDT)


>
> It looks like this patch:
> >Date: Thu, 6 Sep 2001 03:48:16 -0600 (MDT)
> >From: John Marvin jsm@udlkern.fc.hp.com
> >Subject: [parisc-linux-cvs] Patch for SMP support, etc.>
> >A rather large patch that includes my current SMP support changes, plus
> >a variety of other fixes/changes.
>
> did something. But it's so large I'm not sure what exactly :-)
>
> Jurriaan
>

I was pretty sure my changes to handle_break (in traps.c) would fix that
problem.  When I read your note I remembered that I had seen a similar
problem and fixed it.  The kernel would hang when a user program executed
a break instruction (either intentionally or not) without an attached
debugger. That is the problem you were seeing.

However, now that the machine doesn't hang, I am not sure if the remaining
problem you are seeing is a kernel bug or a userland bug.  It would appear
that you are executing 0's (0x00000000 is a break instruction). That
should cause the kernel to send you a SIGTRAP signal. I just checked some
of your old mail, and it looks like you are getting a SIGTRAP. One thing
that looks strange is that you are getting signals delivered using stack
addresses both at ~0xfaf00000 and ~0xbff00000. I wonder if make is using
an alternate signal stack?

John