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Date: Tue, 05 Apr 2011 13:33:22 -0700
From: Julian Elischer <julian@freebsd.org>
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To: Justin Hibbits <chmeeedalf@gmail.com>
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Cc: FreeBSD Current <current@freebsd.org>
Subject: Re: KGDB stack traces in the kernel.
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On 4/4/11 6:04 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.
>
> - Justin
>
I'll try adding NULL when we build the intial stack up.
:-)