Description of problem:
KVM allows to passthrough USB devices to the virtual machine.
This is done with the --usbdevice parameter. Syntax is:
–usbdevice host:1234:5678,
where 1234=vendor id, and 5678=product id.
But there is a problem if you have two *identical* USB devices (e.g. two smartcard readers, or two USB mice), in which case it's not possible to direct one USB device to virtual machine 1 and the second USB device to virtual machine 2. This happens for *identical* USB devices, where the vendor id and the product id is the same for botth.
In Virtualbox for example it's possible to distingish those devices. They realized it by adding a third parameter, the Serial number of the USB device.
This value is given in the "lsusb" output as "iSerial" field.
How reproducible:
Just add two identical USB devices (e.g. smartcard readers or USB mice from the same vendor) and try to pass each of them to different virtual machines.
Additional info:
My proposal is, that in qemu-kvm the --usbdevice parameter should be extended like this
--usbdevice host:<vendor id>[:<product id>[:<serial number>]
In addition corresponing options to select that in virt-manager would be helpful as well.
The '-usbdevice' argument is one of the legacy syntax options with QEMU. USB devices are now specified using the generic '-device' option. None the less, it should be possible to make this new argument take a USB serial number as you suggest.
Comment 2Fedora Admin XMLRPC Client
2012-03-15 17:58:43 UTC
This package has changed ownership in the Fedora Package Database. Reassigning to the new owner of this component.