VGA Passthrough error: Device does not support requested feature x-vga

Char

New Member
Jul 16, 2017
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0
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Hello friends,

I use PVE 4.4 and want to passthrough ATI 6450 (UEFI Compatble) to virtual machine Windows 10 x64

When I simply add
Code:
hostpci0: 01:00, x-vga=on, pcie=1
in vmid.conf file, I get error:

kvm: -device vfio-pci,host=01:00.1,id=hostpci0.0,bus=ich9-pcie-port-1,addr=0x0.0,x-vga=on,multifunction=on: vfio: Device does not support requested feature x-vga
kvm: -device vfio-pci,host=01:00.1,id=hostpci0.0,bus=ich9-pcie-port-1,addr=0x0.0,x-vga=on,multifunction=on: Device initialization failed
and I can see, that PVE make wrong passthrough string:

Code:
-device 'vfio-pci,host=01:00.1,id=hostpci0.0,bus=ich9-pcie-port-1,addr=0x0.0,x-vga=on,multifunction=on'
-device 'vfio-pci,host=01:00.0,id=hostpci0.1,bus=ich9-pcie-port-1,addr=0x0.1'
01:00.0 - videoadapter
01:00.1 - is a sound device of videoadapter

if I change this string to correct value:

Code:
-device 'vfio-pci,host=01:00.0,id=hostpci0.0,bus=ich9-pcie-port-1,addr=0x0.0,x-vga=on,multifunction=on'
-device 'vfio-pci,host=01:00.1,id=hostpci0.1,bus=ich9-pcie-port-1,addr=0x0.1'
and run manually from command line:

Code:
#!/bin/sh
/usr/bin/kvm -id 100 -chardev 'socket,id=qmp,path=/var/run/qemu-server/100.qmp,server,nowait' \
-mon 'chardev=qmp,mode=control' -pidfile /var/run/qemu-server/100.pid -daemonize \
-smbios 'type=1,uuid=3e4d90f4-734f-4bad-83fe-3d1d7556516b' -name win10 -smp '4,sockets=1,cores=4,maxcpus=4' -nodefaults \
-boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' -vga none -nographic -no-hpet \
-cpu 'kvm64,+lahf_lm,+sep,+kvm_pv_unhalt,+kvm_pv_eoi,hv_vendor_id=proxmox,hv_spinlocks=0x1fff,hv_vapic,hv_time,hv_reset,hv_vpindex,hv_runtime,hv_relaxed,enforce,kvm=off' \
-m 8192 -k en-us \
-device 'pci-bridge,id=pci.2,chassis_nr=2,bus=pci.0,addr=0x1f' \
-device 'pci-bridge,id=pci.1,chassis_nr=1,bus=pci.0,addr=0x1e' \
-device 'piix3-usb-uhci,id=uhci,bus=pci.0,addr=0x1.0x2' \
-device 'usb-tablet,id=tablet,bus=uhci.0,port=1' \
-device 'vfio-pci,host=01:00.0,id=hostpci0.0,bus=pci.0,addr=0x10.0,x-vga=on,multifunction=on' \
-device 'vfio-pci,host=01:00.1,id=hostpci0.1,bus=pci.0,addr=0x10.1' \
-device 'vfio-pci,host=06:00.0,id=hostpci1,bus=pci.0,addr=0x11' \
-device 'vfio-pci,host=05:00.0,id=hostpci2,bus=pci.0,addr=0x1b' \
-device 'virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3' -iscsi 'initiator-name=iqn.1993-08.org.debian:01:237f992a4ebe' \
-drive 'file=/vmprox/template/iso/virtio-win-0.1.137.iso,if=none,id=drive-ide0,media=cdrom,aio=threads' \
-device 'ide-cd,bus=ide.0,unit=0,drive=drive-ide0,id=ide0,bootindex=200' \
-drive 'file=/vmprox/template/iso/ru-en_windows_10_x86-x64_20in1_KMS-activation.iso,if=none,id=drive-ide2,media=cdrom,aio=threads' \
-device 'ide-cd,bus=ide.1,unit=0,drive=drive-ide2,id=ide2,bootindex=201' \
-device 'virtio-scsi-pci,id=scsihw0,bus=pci.0,addr=0x5' \
-drive 'file=/vmdata/images/100/vm-100-disk-3.raw,if=none,id=drive-scsi1,format=raw,cache=none,aio=native,detect-zeroes=on' \
-device 'scsi-hd,bus=scsihw0.0,channel=0,scsi-id=0,lun=1,drive=drive-scsi1,id=scsi1' \
-netdev 'type=tap,id=net0,ifname=tap100i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown' \
-device 'e1000,mac=CA:75:AC:33:D4:07,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300' -rtc 'driftfix=slew,base=localtime' \
-global 'kvm-pit.lost_tick_policy=discard'
vga passthrough work perfectly.

In case x-vga=on, but no pcie
Code:
hostpci0: 01:00, x-vga=on
problem remains the same:

PVE make wrong strings:
Code:
-device 'vfio-pci,host=01:00.1,id=hostpci0.0,bus=pci.0,addr=0x10.0,x-vga=on,multifunction=on' \
-device 'vfio-pci,host=01:00.0,id=hostpci0.1,bus=pci.0,addr=0x10.1' \
and generate error, wnen i start vm.

if i change to correct values:
Code:
-device 'vfio-pci,host=01:00.0,id=hostpci0.0,bus=pci.0,addr=0x10.0,x-vga=on,multifunction=on' \
-device 'vfio-pci,host=01:00.1,id=hostpci0.1,bus=pci.0,addr=0x10.1' \
and run vm from console, all works perfectly.


I get this problem with q35 chipset and i440fx chipset with both ovmf and seabios.

Does anyone knows how to solve this problem?
 
Last edited:

dcsapak

Proxmox Staff Member
Staff member
Feb 1, 2016
4,756
462
103
32
Vienna
yes this is a bug, which is/will be fixed in qemu-server 4.0-111
as a workaround you can write:

Code:
hostpci0: 01:00.0;01:00.1,x-vga=on
 
  • Like
Reactions: Char

Char

New Member
Jul 16, 2017
2
0
1
41
yes this is a bug, which is/will be fixed in qemu-server 4.0-111
Thank you, can you post me a link to this bug on proxmox ve bugzilla (or maillist)?

UPD: Is that right Bugzilla link for this bug?
 
Last edited:

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