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Date: Tue, 01 Dec 2009 15:53:13 +0100
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] Permit zero-sized qemu_malloc() & friends
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To: Avi Kivity <avi@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>, qemu-devel@nongnu.org

On 12/01/09 15:34, Avi Kivity wrote:
> On 12/01/2009 02:40 PM, Gerd Hoffmann wrote:
>>
>> Even more advanced: Make zero_length_malloc page-sized and
>> page-aligned, then munmap int, so dereferencing it actually traps.
>
> That will cause vma fragmentation.

I was thinking about a single unmapped page, which wouldn't cause 
fragmentation.  But that is a bad idea too for other reasons ...

cheers,
   Gerd