Date: Thu, 29 Nov 2007 14:05:14 +0200 (EET)
From: Pekka J Enberg <penberg@cs.helsinki.fi>
To: Vegard Nossum <vegard.nossum@gmail.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: [RFC] kmemcheck: trap uses of uninitialized memory (v2)
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Hi Vegard,

On Thu, 29 Nov 2007, Vegard Nossum wrote:
> If I understand you correctly, you only want to be notified if any
> memory within an allocation is used before any memory within the
> allocation has been initialized. I think that this would be quite
> useless compared to tracking all the bytes of an allocation.

Ok, why is it useless? I am trying to understand what kind of errors you 
hope to catch here.

On Thu, 29 Nov 2007, Vegard Nossum wrote:
> I am not truly concerned about the memory usage; this kind of error 
> detection is by definition slow and memory intense.

There's "slow" and then there's "too slow for mainline" :-). But even if 
you want to track every byte, you could use a bitmap in the slab layer to 
cut down memory usage and get rid of "shadow pages", no?

			Pekka
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