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Date: Sun, 4 Apr 2004 20:38:25 +0200
From: Muli Ben-Yehuda <mulix@mulix.org>
To: Sergiy Lozovsky <serge_lozovsky@yahoo.com>
Cc: Andi Kleen <ak@muc.de>, linux-kernel@vger.kernel.org
Subject: Re: kernel stack challenge
Message-ID: <20040404183825.GA18536@mulix.org>
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On Sun, Apr 04, 2004 at 11:24:38AM -0700, Sergiy Lozovsky wrote:

> I wonder how it is possible to access task struct
> having current stack pointer. %esp points at the
> middle of the stack (when we are in the kernel) when
> interrupt occures.

Look at the curren()t and get_current() macros. Basically, the stack
is page aligned, so with the proper masking of %esp you can get to the
bottom of the stack.=20

See http://www.kernelnewbies.org/faq/, "how does get_current work?".=20

Cheers,=20
Muli=20
--=20
Muli Ben-Yehuda
http://www.mulix.org | http://mulix.livejournal.com/


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