Subject: Re: [PATCH v3 3/6] vbus: add a "vbus-proxy" bus model for vbus_driver objects

From: Avi Kivity <[email-masked]>
Date: Tue, 18 Aug 2009 13:00:25 +0300

On 08/18/2009 12:53 PM, Michael S. Tsirkin wrote:
> I'm not hung up on PCI, myself.  An idea that might help you get Avi
> on-board: do setup in userspace, over PCI.  Negotiate hypercall support
> (e.g.  with a PCI capability) and then switch to that for fastpath. Hmm?
>    

Hypercalls don't nest well.  When a nested guest issues a hypercall, you 
have to assume it is destined to the enclosing guest, so you can't 
assign a hypercall-capable device to a nested guest.

mmio and pio don't have this problem since the host can use the address 
to locate the destination.

-- 
error compiling committee.c: too many arguments to function