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Date: Sat, 28 Mar 2009 20:13:12 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [6907] Introducing qcow2 extensions (Uri Lublin)
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To: qemu-devel@nongnu.org
Cc: uri Lublin <ulublin@redhat.com>

Avi Kivity wrote: 
>
> We should introduce a notion of compatible vs. incompatible extensions.
>
> A compatible extension my be ignored by the qcow2 code if it does not 
> understand the magic number.  An incompatible extension causes an 
> abort.  This allows both more flexibility in how we can change the 
> file format.  I believe ext* does the same thing.

I was assuming that all extensions would be compatible.  I don't like 
the idea of having qcow2 files floating around that require specific 
version of QEMU.

For that, we should just bump to qcow3 (that's what versioning is for, 
right? :-).

Regards,

Anthony Liguori