autotest/autotest — pull request #81 by zhouqt (2011-11-22 14:34:59+00:00)
Title: KVM Test: Update usb related functions and Add new usb_multi_disk test

This request mainly contains two part:
1) Update usb related part in kvm_vm.py, to support checking free port(s) on each usb controller.
2) Add a new kvm test called usb_multi_disk, this case tests block device attached on usb interface.