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From: Keith Owens <kaos@ocs.com.au>
To: Andi Kleen <ak@suse.de>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cache colour task_structs 
In-Reply-To: Your message of "01 Nov 2001 02:43:20 BST."
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Date: Thu, 01 Nov 2001 15:42:12 +1100
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On 01 Nov 2001 02:43:20 +0100, 
Andi Kleen <ak@suse.de> wrote:
>You could do that even today (without slab task_struct) by using a 
>random/coloured at fork time value for esp0.  This could just be a static
>colour counter that is subtracted.
>
>Just don't forget to teach ptrace and proc WCHAN and oops printing about it; 
>they currently use hardcoded stack offsets. It'll also likely break kdb.

Should not affect kdb.  It uses current->esp0 for accessing user regs.
Back trace unwinds the stack until it hits a 0 return address, it just
not check for esp0.