[pve-devel] pve-qemu-kvm: patches cleanup for last git

Alexandre DERUMIER aderumier at odiso.com
Mon Mar 12 08:59:13 CET 2012

> And we I try to live migrate, why tablet on ehci, Migratation start on other node 
> but crash with kvm error message "can not migrate unmigrate device ...." 

>>You can't migrate a VM which uses usb devices from the host. 
>>Note: because of that, we only use ehci if you add a usb device from the host. 

> I see in qemu doc (usb2.txt) that tablet is always on uhci. 
> Maybe because it's a virtual device and migration is not planned to work on ehci 
> ? 
> maybe can we always put tablet on uhci ? 

>>Why does that make sense? 

  Because live migration works with tablet on uhci. (related to my point 2 with hotplug)  

> 2) I'm working on usb hotplug, it's working fine for devices but I can't hotplug 
> ehci controller (very instable in windows/linux). 
> So I need to have usb controller present at vm start. 
> What is the reason to have it activated only when usb devices exist in config at 
> start ? (stabibility ?) 

>>Because ehci does not support live migration. 

 Oh, ok, I thinked it doesn't work only if physical usb device was attached to it, but not if the controller was alone.

>>If you configure a usbhost device with BUS-PORT you can hot-plug that device (physically). 

>>So do we really need hotplug of the ehci controller (why)? 

I was thinking about hot-pluging a usb device,after vm started without usb configuration.
Example : 
I have a host with a lot vm (40vm by exemple), it's impossible to map 1 bus-port to each vm.
And I want, time to time, plug a usb drive to some vm by exemple, to copy some data on it.
How Can I do it for the moment ?



	Alexandre D erumier 
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Fax : 03 20 68 90 81 
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