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Date: Wed, 6 Oct 2004 15:25:33 -0700
From: Andrew Morton <akpm@osdl.org>
To: Pavel Machek <pavel@suse.cz>
Cc: rjw@sisk.pl, linux-kernel@vger.kernel.org, akpm@zip.com.au, agruen@suse.de
Subject: Re: Fix random crashes in x86-64 swsusp
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Pavel Machek <pavel@suse.cz> wrote:
>
> Maybe we should memset freed memory to zero so such bugs are
> prevented?

It would make sense to poison these pages, yes.  Zero would not be a good
choice of value, actually - something like 0xbb would cause nice oopses if
someone used a pointer which was backed by __init memory.

CONFIG_DEBUG_PAGEALLOC will pick up this sort of bug, but that's i386-only.