Emmet is, unfortunately, correct. I had forgotten to re-disable the section in /etc/init.d/mountdevsubfs.sh too.
The devices file itself is created when a usbfs mount is created, using: $ mkdir .usbfs $ sudo mount -n -t usbfs -obusmode=0700,devmode=0600,listmode=0644 usbfs .usbfs $ ls .usbfs 001 002 003 004 005 devices $ cat devices $ cat .usbfs/devices T: Bus=05 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=480 MxCh= 8 B: Alloc= 0/800 us ( 0%), #Int= 0, #Iso= 0 D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=01 MxPS=64 #Cfgs= 1 P: Vendor=0000 ProdID=0000 Rev= 2.06 S: Manufacturer=Linux 2.6.22-14-generic ehci_hcd ... Unless there is some over-arching reason *not* to use usbfs then the best solution is, I think, to amend /etc/init.d/mountdevsubfs.sh so instead of: # # Magic to make /proc/bus/usb work # #mkdir -p /dev/bus/usb/.usbfs #domount usbfs "" /dev/bus/usb/.usbfs -obusmode=0700,devmode=0600,listmode=0644 #ln -s .usbfs/devices /dev/bus/usb/devices #mount --rbind /dev/bus/usb /proc/bus/usb we have # # Magic to give virtual machines (KVM/QEMU, VirtualBox, VMWare, etc) access to host USB devices # mkdir -p /dev/bus/usb/.usbfs domount usbfs "" /dev/bus/usb/.usbfs -obusmode=0700,devmode=0600,listmode=0644 ln -s .usbfs/devices /dev/bus/usb/devices This could be added as an additional stanza (which takes the solution back to amending the "sysvinit" package). The alternative is to add a complete new set of scripts and links, either: /etc/rc.S/S12mountdevusbfs -> /etc/init.d/mountdevusbfs.sh or /etc/rc2.d/S20mountdevusbfs -> /etc/init.d/mountdevusbfs.sh That, coupled with the alteration to KVM/QEMU would solve the issue. Comments please? -- Could not open /proc/bus/usb/devices https://bugs.launchpad.net/bugs/156085 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs