attaching usb dongle to KVM VM
Solution 1
It's probably a problem with access rights. Your QEMU deamon is not allowed to access the USB devices. Try:
chown libvirt-qemu /dev/bus/usb/ -R
or whichever user your KVM is running as. This should do the trick.
Solution 2
To grant permanent access to the raw USB device nodes to the user the hypervisor runs as, you need to create an udev rule; the chown-based answer will only work until the next reboot.
In /lib/udev/rules.d
, create a file like 51-usb_passthrough.rules
:
SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTRS{busnum}=="2" ATTRS{devpath}=="1" GROUP="kvm"
Here I used physical bus and port numbers to target the device (as I prefer passing through the physical port no matter what device is plugged in rather than reconfiguring my VM each time I connect a new device), but of course you can use whatever attributes you want; the GROUP
argument determines the group that will own the device node, this should be whatever user runs the virtual machines.
Run udevadm control --reload-rules
to make the new rule effective immediately (you still need to disconnect/reconnect the USB devices) or simply reboot the host.
Solution 3
Easy solution: connect with
nc -U socket-file
to your QEMU monitor, where socket-file is the path to monitor. How to find: ps -FA | grep qemu. You will find there at the command line.
And run the command at the monitor:
device_add usb-host,id=<ANY string>,hostbus=<BUS>,hostport=<PORT>
this is pass-through by port number. You can pass through any device with any VID/PID. You can also pass-through particular devices using
device_add usb-host,id=<ANY string>,vendorid=0x0461,productid= 0x0010
and they can be plugged in to any port of your host.
Helpful commands also:
info usbhost
info usb
Related videos on Youtube
csch
Updated on September 18, 2022Comments
-
csch almost 2 years
I'm struggling to connect a usb device, that gets detected correctly by the host, to a kvm vm.
I have a freshly installed Ubuntu Server 14.10 as KVM/QEMU host. I set up an Ubuntu vm using this command:
virt-install --connect qemu:///system \ -n test01 \ -r 1024 \ --vcpus=2 \ --disk path=/vmstorage/01/test01.img,size=5 \ --vnc \ --noautoconsole \ --os-variant=ubuntuutopic \ --hvm \ --cdrom /path/to/ubuntu-14.10-server-i386.iso
After the successful installation a
virsh dumpxml test01
returns<domain type='kvm' id='16'> <name>test01</name> <uuid>f58ca825-c999-4168-9f5a-616057d9955d</uuid> <memory unit='KiB'>1048576</memory> <currentMemory unit='KiB'>1048576</currentMemory> <vcpu placement='static'>2</vcpu> <resource> <partition>/machine</partition> </resource> <os> <type arch='x86_64' machine='pc-i440fx-utopic'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> <apic/> <pae/> </features> <cpu mode='custom' match='exact'> <model fallback='allow'>SandyBridge</model> </cpu> <clock offset='utc'> <timer name='rtc' tickpolicy='catchup'/> <timer name='pit' tickpolicy='delay'/> <timer name='hpet' present='no'/> </clock> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <emulator>/usr/bin/kvm-spice</emulator> <disk type='file' device='disk'> <driver name='qemu' type='raw'/> <source file='/vmstorage/01/test01.img'/> <backingStore/> <target dev='vda' bus='virtio'/> <alias name='virtio-disk0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> </disk> <disk type='block' device='cdrom'> <driver name='qemu' type='raw'/> <backingStore/> <target dev='hda' bus='ide'/> <readonly/> <alias name='ide0-0-0'/> <address type='drive' controller='0' bus='0' target='0' unit='0'/> </disk> <controller type='usb' index='0' model='ich9-ehci1'> <alias name='usb0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x7'/> </controller> <controller type='usb' index='0' model='ich9-uhci1'> <alias name='usb0'/> <master startport='0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0' multifunction='on'/> </controller> <controller type='usb' index='0' model='ich9-uhci2'> <alias name='usb0'/> <master startport='2'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x1'/> </controller> <controller type='usb' index='0' model='ich9-uhci3'> <alias name='usb0'/> <master startport='4'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x2'/> </controller> <controller type='pci' index='0' model='pci-root'> <alias name='pci.0'/> </controller> <controller type='ide' index='0'> <alias name='ide0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <interface type='bridge'> <mac address='52:54:00:11:b2:c1'/> <source bridge='br0'/> <target dev='vnet0'/> <model type='virtio'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> <serial type='pty'> <source path='/dev/pts/0'/> <target port='0'/> <alias name='serial0'/> </serial> <console type='pty' tty='/dev/pts/0'> <source path='/dev/pts/0'/> <target type='serial' port='0'/> <alias name='serial0'/> </console> <input type='mouse' bus='ps2'/> <input type='keyboard' bus='ps2'/> <graphics type='vnc' port='5900' autoport='yes' listen='0.0.0.0'> <listen type='address' address='0.0.0.0'/> </graphics> <video> <model type='cirrus' vram='9216' heads='1'/> <alias name='video0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> <memballoon model='virtio'> <alias name='balloon0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> </memballoon> </devices> <seclabel type='dynamic' model='apparmor' relabel='yes'> <label>libvirt-f58ca825-c999-4168-9f5a-616057d9955d</label> <imagelabel>libvirt-f58ca825-c999-4168-9f5a-616057d9955d</imagelabel> </seclabel> </domain>
I now want to attach an USB stick. After some googleing I found some sources that basically all suggest the following approach:
- attach stick to host
-
get vendor- and product-id
root@host01:~# lsusb Bus 002 Device 004: ID 13fe:5100 Kingston Technology Company Inc. Flash Drive Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 004: ID 0624:0249 Avocent Corp. Bus 001 Device 003: ID 0624:0248 Avocent Corp. Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
-
add new config-snippet to vm via
virsh edit test01
<devices> <!- ... -> <hostdev mode='subsystem' type='usb' managed='yes'> <source> <vendor id='0x13fe'/> <product id='0x5100'/> </source> </hostdev> </devices/>
restart vm
After that the vm should see the stick via
lsusb
, but nothing changes. If I try to attach the device to a second vm though,virsh start <othervm>
fails witherror: Requested operation is not valid: USB device 002:003 is in use by driver QEMU, domain test01
BUT I can still mount and access the stick on the host. I tried different sticks and different vm-operating systems (ubuntu and windows), no success.Some instructions suggest to turn off apparmor, but a
/etc/init.d/apparmor stop
didn't change anything.This is driving me nuts, since I don't get any error or log messages and I have no clue how to find out what's wrong. Any ideas on how to get the usb connected to the vm, or at least, how to analyse it further?
-
Admin over 9 yearsThis would only work temporarily until the next reboot; see my answer for a permanent solution.
-
Natus Drew over 8 yearsthis didn't solve the problem for me
-
Max almost 7 yearsI had the same issue with ubuntu 16.04 and this didn't work for me. I found I need to modify the apparmor configuration as described in Ubuntu KVM passthrough wiki: help.ubuntu.com/community/KVM/…
-
rabexc over 6 yearsNote that instead of using netcat, you can likely use libvirt and virsh directly with something like
virsh -c qemu:///system qemu-monitor-command --hmp test01 "device_add usb-host,..."
.