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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] Re: [PATCH 0/9] Virtio cleanups
Date: Mon, 22 Mar 2010 16:16:29 +0000
References: <cover.1268765204.git.quintela@redhat.com>
	<20100322151742.GA19675@redhat.com> <4BA791D6.805@codemonkey.ws>
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Juan Quintela <quintela@redhat.com>, qemu-devel@nongnu.org, "Michael S. Tsirkin" <mst@redhat.com>

> But look at the lguest virtio implement.  We would definitely model a
> VirtIOBus if we implemented something like that in qemu.  VirtIO really
> is designed to be a bus.

When you say "bus" you actually mean point-point connection, right[1]?
I don't see anything in virtio that allows arbitration of multiple devices, or 
any particular need for one as it can be handled by the host bus bindings.

Paul

[1] Technically I suppose a p-t-p connection is a degenerate case of a bus. 
While modern hardware busses (USB, PCIe) are electrically point-point, 
logically they are usually a shared bus topology.