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From: John Baldwin <jhb@freebsd.org>
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Date: Wed, 6 Apr 2011 08:37:50 -0400
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	(bigwig.baldwin.cx); Wed, 06 Apr 2011 08:45:13 -0400 (EDT)
Cc: Justin Hibbits <chmeeedalf@gmail.com>,
	FreeBSD Current <current@freebsd.org>
Subject: Re: KGDB stack traces in the kernel.
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On Monday, April 04, 2011 9:04:23 pm Justin Hibbits wrote:
> On Apr 4, 2011, at 6:57 PM, Julian Elischer wrote:
> > is there anyone here with enough gdb/kgdb source experience to know  
> > what
> > we would need to put on the stack at fork_exit() to make it stop  
> > when it
> > gets there?
> >
> > not only is it annoying but it slows down debugging because kgdb and  
> > the ddd
> > front end ask for stacks a LOT. sometimes it actually just hangs as  
> > the stack
> > goes into a loop and never ends.
> >
> > I had a quick look but didn't spot how gdb decides it has reached  
> > the end of a stack.
> >
> > Julian
> 
>  From my experience, it checks for a NULL stack chain pointer.  Once  
> that reaches NULL, it's the end of the stack.

No, I removed that because it broke debugging panics due to NULL function 
pointers.

-- 
John Baldwin