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From: Justin Hibbits <chmeeedalf@gmail.com>
To: Julian Elischer <julian@freebsd.org>
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Date: Mon, 4 Apr 2011 21:04:23 -0400
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Cc: FreeBSD Current <current@freebsd.org>
Subject: Re: KGDB stack traces in the kernel.
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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.

- Justin