On Tue, Jun 01, 2010 at 12:49:05PM -0400, Cole Robinson wrote: > On 05/28/2010 02:09 PM, Andreas Ntaflos wrote: > > Hello list, > > > > this may be off topic but it is closely related to my Libvirt adventures > > so maybe you can help me. > > > > I want to pass a USB device (a USB Huawei E620 modem) through to a KVM > > guest. Pass-through in general works fine and the modem is visible in > > the guest. However, the host still sees it and sometimes tries to access > > it (such modems seem to also be USB storage devices). This naturally > > leads to conflicts and I believe this crashed the guest very badly > > yesterday. > > > > So I am looking for a way to make sure the host passes through the USB > > device (in its entirety) without trying to touch it and claim it as its > > own. Preferably without disabling the USB storage subsystem completely > > on the host. > > > > Any ideas? Is there a best practice for such things in the Libvirt > > world? Or any other world? > > > > For PCI devices, libvirt automatically performs a device reset and some > other voodoo to make sure the host doesn't try to use the device. Maybe > there is something similar that libvirt can do for USB devices as well? > I'm not very knowledgable about that stuff so I can't say for certain. Yes there is the same. We need to finish implementing identical infrastructure to that used for PCI devices. We need to do resets and bind/unbind host device drivers, and implement the so called 'managed' mode. Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|
