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Date: Wed, 13 Jun 2012 14:55:53 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] Semantics of DeviceState::realized and
	BlockDriverState
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To: Markus Armbruster <armbru@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, qemu-devel <qemu-devel@nongnu.org>, Anthony Liguori <anthony@codemonkey.ws>, =?ISO-8859-1?Q?Andreas_F=E4rber?= <afaerber@suse.de>

Il 13/06/2012 14:53, Markus Armbruster ha scritto:
>> > This behavior is necessary to allow overriding backing files.
> Could you explain why we need to override backing files between open and
> attach?

Open tells us that you need a backing file.

After attach, state should be finalized.

Hence, between open and attach is the only time when you can override
backing files.

> Can you give another example of something we need to be able to do
> between open and attach?

I can't think of anything.

Paolo