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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] RFC: usb redirection over the network,
	=?iso-8859-1?q?=09interesting_outside_of?= spice?
Date: Mon, 29 Nov 2010 17:13:22 +0000
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To: qemu-devel@nongnu.org
Cc: spice-devel@lists.freedesktop.org, =?iso-8859-1?q?Fran=E7ois_Revol?= <revol@free.fr>, Gerd Hoffmann <kraxel@redhat.com>

>    Hi,
> 
> > Not me at the moment, but unless you tunnel it inside another
> > protocol, you'd really want to look at the existing USB-over-IP
> > protocols instead of reinventing the wheel:
> > http://usbip.sourceforge.net/ (some support in Linux already IIRC)
> > (and there are others which I don't recall)
> 
> Doesn't look very useful on a quick glance.
> 
> First: Yes, we wanna embed this into other protocol(s).
> 
> Second, seems usbip is implemented using special drivers in kernel space
> for both sides.  We will not need special drivers on the qemu side (we
> just hook up the devices to the emulated hci).  On the client side using
> libusb looks alot more sensible than requiring kernel modules.

I don't know how good the usp/ip stuff is, but I'd be very reluctant to invent 
yet annother remote-usb protocol.  USB is very hairy, so there's good reason 
to go with something that has already been tested.

IMO the ability to interact with the native kernel support is a feature in its 
own right.  If we end up with a libusb implementation of the usb/ip device 
end, then that only seems like a good thing - you potentialy get testing 
coverage from both qemu users and native vhci-hcd users.

Paul