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Subject: Re: Detailed Stack Information Patch [2/3]
From: Stefani Seibold <stefani@seibold.net>
To: Mikael Pettersson <mikpe@it.uu.se>
Cc: Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>,
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Date: Fri, 03 Apr 2009 10:01:08 +0200
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Am Freitag, den 03.04.2009, 09:32 +0200 schrieb Mikael Pettersson:
> Stefani Seibold writes:
>  > I think a user space daemon will be the a good way if the /proc/*/maps
>  > or /proc/*/stack will provide the following information:
>  > 
>  > - start address of the stack
>  > - current address of the stack pointer
>  > - highest used address in the stack
> 
> You're assuming
> 1. a thread has exactly one stack
> 2. the stack is a single unbroken area
> 3. the kernel knows the location of this area
> 
> None of these assumptions are necessarily valid, esp. in
> the presence of virtualizers, managed runtimes, or mixed
> interpreted/JIT language implementations.

We are talking about the kernel view. And from this point a thread has
only one stack and it is a single mapped continuous area. There are only
one exception and that is the sigaltstack().