Re: [Qemu-devel] Re: [PATCH 08/12] block: Catch attempt to attach multiple devices to a blockdev

[Christoph Hellwig]

On Mon, Jun 28, 2010 at 10:24:49AM +0200, Kevin Wolf wrote:
> How would breaking compatibility help us? For the user a USB MSD is only
> one device, so requiring two -device parameters sounds wrong.

But it is separate devices.  At least the standards compliant usb
storage devices just are a bride of scsi commands over usb and fit into
the SAM device model, which makes a difference between initiator, target
and LUN.  So having a different device for the specific target vs the
initiator port makes a difference. (and yes, we're still totally missing
support for multiple luns, which would require another level of
devices).  Trying to hide this is not all that useful - not anymore
useful than hiding it on a "normal" scsi host controller anyway.