Re: [fedora-virt] USB passthrough and disconnect
On 10/15/2009 09:36 AM, Gianluca Cecchi wrote:
Hello,
following the instructions at
http://www.redhat.com/archives/fedora-virt/2009-June/msg00182.html
I'm able to attach an USB key to my Windows XP SP3 guest.
More better, I'm able to attach and use it with the guest already started.
Very good!
(Actually I don't have SElinux enabled so I skipped what related to it )
The doubt is, when in Windows I then safely remove the key and get the ok
msg from the os, if I try to hot remove the USB device in details windows of
the guest I receive the message that will be effective after reboot.
Is this expected and the hot unplug a feature next to come, or do I miss
anything in correct way to do things?
USB hotunplug isn't supported by libvirt at the moment. I believe this
is because it has historically been difficult to get the proper
information from qemu that is required for hotunplug.
My sw versions for host are F11 x86_64 with up2date rawvirt repo:
libvirt-0.7.1-11.fc11.x86_64
qemu-kvm-0.11.0-6.fc11.x86_64
virt-manager-0.8.0-7.fc11.noarch
Suppose the message is correct behaviour based on current state of things,
what would be correct approach if during a vm session I use several usb keys
for example?
1) insert first usb key in host
2) add hw of first usb key in details tab of guest
3) use it in guest and at the end disconnect it from inside guest OS
4) remove hw in details tab of guest; confirming that this will overwrite
any othe rchanges occured in guest config....
5) remove key form host usb plug
6) insert second usb key in host
7) add hw of second usb key in details tab of guest
8) use it in guest and at the end disconnect it from inside guest OS
9) ? If I do same as 4 do I loose the action made in 4) ??
Yes, you will likely lose the effect of step 4. When the VM shuts down,
USB1 will still appear to be attached.
This is a side effect of how virt-manager interacts with libvirt to
update a running VMs config when hotplug/unplug is not available (as in
the USB hotunplug case, or say trying to hotplug an IDE disk).
We actually should be able to fix in this in virt-manager now, and can
remove the 'This will overwrite any other changes' text. I'll get to it
for the next virt-manager release.
- Cole