USB hardware not autodetected

[mattismyname]

OS: Ubuntu 11.04 x86_64 server image
qemu-kvm: 0.14.0+noroms-0ubuntu4.1

Steps to reproduce problem:
1. Boot a VM
2. Add a USB auto filter for device: virsh qemu-monitor-command oag01 usb_add\ host:*.*:0951:1642
3. Verify filter was added: virsh qemu-monitor-command oag01 info\ usbhost
4. Plug in USB device with appropriate ID
5. Verify device shows in host listing: virsh qemu-monitor-command oag01 info\ usbhost
6. Check for device passed through to guest: virsh qemu-monitor-command oag01 info\ usb

Expected outcome: Device was passed through to guest after plugging it in.
Actual outcome: Device was not passed through to guest (step 6 above produces no output)

[mattismyname (mattismyname)]

I just found the qemu logfile for this VM and saw the following:

husb: open device 2.2
/dev/bus/usb/002/002: Permission denied
husb: open device 2.11
/dev/bus/usb/002/011: Permission denied
husb: open device 6.2
/dev/bus/usb/006/002: Permission denied
husb: open device 2.12
/dev/bus/usb/002/012: Permission denied

Looks to be a likely permissions problem.

[mattismyname (mattismyname)]

Also, this from kern.log:

Jun 27 03:32:51 oah01 kernel: [10894.848750] type=1400 audit(1309170771.373:139): apparmor="DENIED" operation="open" parent=1 profile="libvirt-bb801dd2-829f-0b8a-4702-52cd23f5e090" name="/dev/bus/usb/002/012" pid=3354 comm="kvm" requested_mask="rw" denied_mask="rw" fsuid=102 ouid=102

[Serge Hallyn (serge-hallyn)]

Thanks for taking the time to report this bug.

To work around this, please follow comments #1 and #12 from bug 545795. (If you prefer I can quote them here). That will tell apparmor to allow the accesses you want.

Please let us know if you continue to have problems.

[Serge Hallyn (serge-hallyn)]

I'm setting this bug to triaged as I think the solution should be more discoverable. I'm not however sure how to accomplish that, open to suggestions.