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Message-ID: <4C3E0A4D.6070609@linux.vnet.ibm.com>
Date: Wed, 14 Jul 2010 14:04:45 -0500
From: Anthony Liguori <aliguori@linux.vnet.ibm.com>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] [PATCH] Make default invocation of block drivers
	safer
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To: Aurelien Jarno <aurelien@aurel32.net>
Cc: Kevin Wolf <kwolf@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, Christoph Hellwig <hch@lst.de>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, qemu-devel@nongnu.org

On 07/14/2010 01:54 PM, Aurelien Jarno wrote:
> On Wed, Jul 14, 2010 at 08:43:11PM +0200, Christoph Hellwig wrote:
>    
>> Err, strong NACK.  Please don't start messing with the contents of the
>> data plane, we're getting into real trouble there.  It's perfectly
>> valid for a guest to create an image inside an image, and with hardware
>> support for nested virtualization I guess this use case will become
>> rather common, just as it already is on S/390 with VM.
>>
>>      
> Maybe it should only be done on the hard drive used to boot?
>    

It's just as dangerous on any other disk.  My use of "bootsector" in the 
code is probably misleading.

Regards,

Anthony Liguori