Re: [PATCH 2 of 2] xl: Accept a list for usbdevice in config file

[George Dunlap <george.dunlap@eu.citrix.com>]

On 29/11/12 12:25, Ian Campbell wrote:
> On Thu, 2012-11-29 at 12:20 +0000, George Dunlap wrote:
>> On Thu, Nov 29, 2012 at 11:44 AM, George Dunlap
>> <george.dunlap@eu.citrix.com> wrote:
>>          qemu.git/vl.c suggests other options might include, "disk:",
>>          "serial:", "net:" and "bt:"; other non-colon-including options
>>          include "keyboard", "mouse", "wacom-tablet", and "braile".
>>          
>>          On the other hand, a number of these seem to require
>>          supplementary options to work well; e.g., network and bt
>>          (bluetooth) require one argument to hook up a USB device, and
>>          another option to say how it's connected to what.
>>          
>>          It's also interesting to note that the KVM documentation
>>          doesnt' mention using "-usb" and "-usbdevice" at all -- they
>>          seem to prefer using "-device" to specify hubs &c.
>>
>> Speaking of which, the KVM docs refer to "-usb" and "-usbdevice" as
>> "legacy interfaces", which will only get you piix3.
> This is a concern for other types of device too. We seem to invoke new
> qemu with a mixture of legacy and new-style interfaces.
>
>>    It seems like exposing the full capabilities of qemu would mean
>> either 1) coming up with a full specifciation which we can then
>> translate into qemu directives, as libvirt seems to do, or 2) just
>> recommend people construct their own qemu command-line options to pass
>> through.
> Does libvirt let you care about topologies or just it just automatically
> create a new USB controller for every N devices you add and hook things
> up in some order?

No idea -- I took a quick glance through the libvirt docs and I didn't 
see anything particular about a topology.  I don't have a system set up 
with libvirt, so I can't try it and see what the resulting qemu command 
line looks like :-)

http://libvirt.org/formatdomain.html#elementsUSB

  -George