So I'm passing through my system's built in USB and sound devices to my Windows 10 VM. It's worked for the longest time, but all of the sudden USB does not work (but confusingly enough audio does?!).   Here's the error from my logs:   2016-11-28T05:26:53.587398Z qemu-system-x86_64: vfio: Cannot reset device 0000:00:14.0, no available reset mechanism. 2016-11-28T05:26:53.587451Z qemu-system-x86_64: vfio: Cannot reset device 0000:00:1f.3, no available reset mechanism. 2016-11-28T05:26:55.595408Z qemu-system-x86_64: vfio: Cannot reset device 0000:00:14.0, no available reset mechanism. 2016-11-28T05:26:55.595505Z qemu-system-x86_64: vfio: Cannot reset device 0000:00:1f.3, no available reset mechanism.   Device 14 is my USB controller, 1f.3 is my sound card.   The weirdest thing is that the reset mechanism errors have happened before without impeding my ability to use my USB devices. Perhaps it's a change in something to do with the linux kernel upgrade? I only recently upgraded from 6.2 to 6.2.4   Any ideas? I'm at my wits end; I've been googling for several hours and I kinda need my kb and mouse to do homework   Here's my XML if it helps   <domain type='kvm' id='4'>   <name>Windows 10</name>   <uuid>fbaf2590-f88d-466b-a4a3-e381d683f558</uuid>   <metadata>     <vmtemplate xmlns="unraid" name="Windows 10" icon="windows.png" os="windows10"/>   </metadata>   <memory unit='KiB'>8388608</memory>   <currentMemory unit='KiB'>8388608</currentMemory>   <memoryBacking>     <nosharepages/>     <locked/>   </memoryBacking>   <vcpu placement='static'>6</vcpu>   <cputune>     <vcpupin vcpu='0' cpuset='0'/>     <vcpupin vcpu='1' cpuset='1'/>     <vcpupin vcpu='2' cpuset='2'/>     <vcpupin vcpu='3' cpuset='4'/>     <vcpupin vcpu='4' cpuset='5'/>     <vcpupin vcpu='5' cpuset='6'/>   </cputune>   <resource>     <partition>/machine</partition>   </resource>   <os>     <type arch='x86_64' machine='pc-i440fx-2.5'>hvm</type>     <loader readonly='yes' type='pflash'>/usr/share/qemu/ovmf-x64/OVMF_CODE-pure-efi.fd</loader>     <nvram>/etc/libvirt/qemu/nvram/fbaf2590-f88d-466b-a4a3-e381d683f558_VARS-pure-efi.fd</nvram>   </os>   <features>     <acpi/>     <apic/>     <hyperv>       <relaxed state='on'/>       <vapic state='on'/>       <spinlocks state='on' retries='8191'/>       <vendor id='none'/>     </hyperv>   </features>   <cpu mode='host-passthrough'>     <topology sockets='1' cores='3' threads='2'/>   </cpu>   <clock offset='localtime'>     <timer name='hypervclock' present='yes'/>     <timer name='hpet' present='no'/>   </clock>   <on_poweroff>destroy</on_poweroff>   <on_reboot>restart</on_reboot>   <on_crash>restart</on_crash>   <devices>     <emulator>/usr/local/sbin/qemu</emulator>     <disk type='file' device='disk'>       <driver name='qemu' type='raw' cache='writeback'/>       <source file='/mnt/user/vdisks/Windows 10/vdisk1.img'/>       <backingStore/>       <target dev='hdc' bus='virtio'/>       <boot order='1'/>       <alias name='virtio-disk2'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>     </disk>     <disk type='file' device='disk'>       <driver name='qemu' type='raw' cache='writeback'/>       <source file='/mnt/user/vdisks2/Windows 10/Windows 10/vdisk2.img'/>       <backingStore/>       <target dev='hdd' bus='virtio'/>       <alias name='virtio-disk3'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>     </disk>     <disk type='file' device='cdrom'>       <driver name='qemu' type='raw'/>       <source file='/mnt/user/install/isos/virtio-win-0.1.118.iso'/>       <backingStore/>       <target dev='hda' bus='ide'/>       <readonly/>       <boot order='2'/>       <alias name='ide0-0-0'/>       <address type='drive' controller='0' bus='0' target='0' unit='0'/>     </disk>     <controller type='usb' index='0' model='nec-xhci'>       <alias name='usb'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>     </controller>     <controller type='pci' index='0' model='pci-root'>       <alias name='pci.0'/>     </controller>     <controller type='ide' index='0'>       <alias name='ide'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>     </controller>     <controller type='virtio-serial' index='0'>       <alias name='virtio-serial0'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>     </controller>     <interface type='bridge'>       <mac address='52:54:00:45:34:46'/>       <source bridge='br0'/>       <target dev='vnet0'/>       <model type='virtio'/>       <alias name='net0'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x02' 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>     <channel type='unix'>       <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-Windows 10/org.qemu.guest_agent.0'/>       <target type='virtio' name='org.qemu.guest_agent.0' state='disconnected'/>       <alias name='channel0'/>       <address type='virtio-serial' controller='0' bus='0' port='1'/>     </channel>     <hostdev mode='subsystem' type='pci' managed='yes'>       <driver name='vfio'/>       <source>         <address domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>       </source>       <alias name='hostdev0'/>       <rom file='/mnt/user/install/drivers/vbios.dump'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>     </hostdev>     <hostdev mode='subsystem' type='pci' managed='yes'>       <driver name='vfio'/>       <source>         <address domain='0x0000' bus='0x01' slot='0x00' function='0x1'/>       </source>       <alias name='hostdev1'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x08' function='0x0'/>     </hostdev>     <hostdev mode='subsystem' type='pci' managed='yes'>       <driver name='vfio'/>       <source>         <address domain='0x0000' bus='0x00' slot='0x1f' function='0x3'/>       </source>       <alias name='hostdev2'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>     </hostdev>     <hostdev mode='subsystem' type='pci' managed='yes'>       <driver name='vfio'/>       <source>         <address domain='0x0000' bus='0x00' slot='0x14' function='0x0'/>       </source>       <alias name='hostdev3'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/>     </hostdev>     <hostdev mode='subsystem' type='pci' managed='yes'>       <driver name='vfio'/>       <source>         <address domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>       </source>       <alias name='hostdev4'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x0b' function='0x0'/>     </hostdev>     <memballoon model='virtio'>       <alias name='balloon0'/>       <address type='pci' domain='0x0000' bus='0x00' slot='0x0c' function='0x0'/>     </memballoon>   </devices> </domain>   And here's my lspci output   00:00.0 Host bridge [0600]: Intel Corporation Skylake Host Bridge/DRAM Registers [8086:1918] (rev 07) 00:01.0 PCI bridge [0604]: Intel Corporation Skylake PCIe Controller (x16) [8086:1901] (rev 07) 00:14.0 USB controller [0c03]: Intel Corporation Sunrise Point-H USB 3.0 xHCI Controller [8086:a12f] (rev 31) 00:16.0 Communication controller [0780]: Intel Corporation Sunrise Point-H CSME HECI #1 [8086:a13a] (rev 31) 00:17.0 SATA controller [0106]: Intel Corporation Sunrise Point-H SATA controller [AHCI mode] [8086:a102] (rev 31) 00:1c.0 PCI bridge [0604]: Intel Corporation Sunrise Point-H PCI Express Root Port #5 [8086:a114] (rev f1) 00:1d.0 PCI bridge [0604]: Intel Corporation Sunrise Point-H PCI Express Root Port #9 [8086:a118] (rev f1) 00:1d.2 PCI bridge [0604]: Intel Corporation Sunrise Point-H PCI Express Root Port #11 [8086:a11a] (rev f1) 00:1d.3 PCI bridge [0604]: Intel Corporation Sunrise Point-H PCI Express Root Port #12 [8086:a11b] (rev f1) 00:1f.0 ISA bridge [0601]: Intel Corporation Sunrise Point-H LPC Controller [8086:a14a] (rev 31) 00:1f.2 Memory controller [0580]: Intel Corporation Sunrise Point-H PMC [8086:a121] (rev 31) 00:1f.3 Audio device [0403]: Intel Corporation Sunrise Point-H HD Audio [8086:a170] (rev 31) 00:1f.4 SMBus [0c05]: Intel Corporation Sunrise Point-H SMBus [8086:a123] (rev 31) 00:1f.6 Ethernet controller [0200]: Intel Corporation Ethernet Connection (2) I219-LM [8086:15b7] (rev 31) 01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GP104 [GeForce GTX 1070] [10de:1b81] (rev a1) 01:00.1 Audio device [0403]: NVIDIA Corporation GP104 High Definition Audio Controller [10de:10f0] (rev a1) 02:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM1142 USB 3.1 Host Controller [1b21:1242] 03:00.0 Non-Volatile memory controller [0108]: Samsung Electronics Co Ltd NVMe SSD Controller [144d:a802] (rev 01) 04:00.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1083/1085 PCIe to PCI Bridge [1b21:1080] (rev 04) 05:01.0 USB controller [0c03]: VIA Technologies, Inc. VT82xx/62xx UHCI USB 1.1 Controller [1106:3038] (rev 62) 05:01.1 USB controller [0c03]: VIA Technologies, Inc. VT82xx/62xx UHCI USB 1.1 Controller [1106:3038] (rev 62) 05:01.2 USB controller [0c03]: VIA Technologies, Inc. USB 2.0 [1106:3104] (rev 65) 05:01.3 FireWire (IEEE 1394) [0c00]: VIA Technologies, Inc. VT6306/7/8 [Fire II(M)] IEEE 1394 OHCI Controller [1106:3044] (rev 46) 06:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM1142 USB 3.1 Host Controller [1b21:1242]