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Subject: [Qemu-devel] Re: [PATCH v2 3/7] docs: Add QED image format
	specification
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To: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org, Christoph Hellwig <hch@lst.de>

  On 10/11/2010 05:30 PM, Stefan Hajnoczi wrote:
> >
> >  It was discussed before, but I don't think we came to a conclusion. Are
> >  there any circumstances under which you don't want to set the
> >  QED_CF_BACKING_FORMAT flag?
>
> I suggest the following:
>
> QED_CF_BACKING_FORMAT_RAW = 0x1
>
> When set, the backing file is a raw image and should not be probed for
> its file format.  The default (unset) means that the backing image file
> format may be probed.
>
> Now the backing_fmt_{offset,size} are no longer necessary.

Should it not be an incompatible option?  If the backing disk starts 
with a format magic, it will be probed by an older qemu, incorrectly.

-- 
error compiling committee.c: too many arguments to function