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Date: Sat, 26 Jun 2010 12:11:46 +0200
From: Christoph Hellwig <hch@lst.de>
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References: <1277484812-22012-1-git-send-email-armbru@redhat.com>
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Subject: [Qemu-devel] Re: [PATCH 08/12] block: Catch attempt to attach
	multiple devices to a blockdev
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To: Markus Armbruster <armbru@redhat.com>
Cc: kwolf@redhat.com, hch@lst.de, qemu-devel@nongnu.org, kraxel@redhat.com

On Fri, Jun 25, 2010 at 06:53:28PM +0200, Markus Armbruster wrote:
> For instance, -device scsi-disk,drive=foo -device scsi-disk,drive=foo
> happily creates two SCSI disks connected to the same block device.
> It's all downhill from there.

And from some quick testing a while ago the thing seems to actually
work.  Not that I think that it is a good idea, but do we want to change
behaviour in that respect?

> Device usb-storage deliberately attaches twice to the same blockdev,
> which fails with the fix in place.  Detach before the second attach
> there.

Can anyone explain what the hell usb storage is actually trying to do
with the two drives?