[vfio-users] GPU HDMI audio passthrough weird behavior?

Muted Bytes mutedbytes at gmail.com
Sun Apr 24 10:07:41 UTC 2016

Yes, I tried removing multifunction=on and removing addr=00.1, which
resulted in the device error code.

Also, the device and subsystem ids appear to be correct in the guest, as in
they match what is shown in lspci, so its weird that the Acer stuff shows
up at all. I actually can't find any reference to this "graphics dock" in
device manager except that it shows up as a removable device in Windows
tray and in control panel devices (where printers are listed), but it is
quite bothersome nonetheless.
On Apr 23, 2016 9:53 PM, "Karsten Mettke" <k.mettke at d4net.de> wrote:

Did you set the target address to a different Slot? Code 10 happened when I
was trying to set the hdmi card to the same Slot the GPU was,but to
function x01.‎
I am starting the kernel with
kvm.allow_unsafe_assigned_interrupts=1 kvm.ignore_msrs=1
It was required for the GPU already so i dontknow if that would help with
hdmi. Ommitting those would cause the vm not to start with either code 10
or a Lot of dmesg entries about blocked/invalid msrs

I guess it is grouping it because the device ID is messed up, and windows
thinks it is a different device, in your case the Acer dock.

Karsten Mettke.

Disclaimer: i am just a nerd :)
*Von: *Muted Bytes
*Gesendet: *Sonntag, 24. April 2016 09:27
*An: *Karsten Mettke; vfio-users
*Betreff: *Re: AW: [vfio-users] GPU HDMI audio passthrough weird behavior?

Thanks for the suggestion, however if I try to separate out the function
then I get a code 10 error and device cannot start.

Ultimately, I'm wondering why Windows is grouping the gpu hdmi audio bus
and controller as an external Acer "graphics dock" when no such thing
exists in the system.
On Apr 23, 2016 6:54 PM, "Karsten Mettke" <k.mettke at d4net.de> wrote:

Maybe i should clarify. I meant passing them seperate into own Slots in the
guest. This way you can ommit multifunction=on. Which Made it working for

Gesendet von meinem BlackBerry 10-Smartphone.
Von: Muted Bytes
Gesendet: Sonntag, 24. April 2016 04:47
An: vfio-users
Betreff: [vfio-users] GPU HDMI audio passthrough weird behavior?

Hi all,

Has anyone experienced weird behavior when assigning HDMI function of
GPU along with the GPU itself in Windows guest? In my case, I have:

02:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc.
[AMD/ATI] Pitcairn XT [Radeon HD 7870 GHz Edition] [1002:6818]
02:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI]
Cape Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series]

and pass these through using
-device vfio-pci,host=02:00.0,addr=00.0,multifunction=on \
-device vfio-pci,host=02:00.1,addr=00.1 \

however, in the guest the 1002:aab0 HDMI Audio shows up under system
devices as a "High Definition Audio Bus" rather than an HDMI
device/controller, and what shows up as the "AMD High Definition Audio
Device" itself is something which is 1002:aa01. Where does this
1002:aa01 come from? Is this correct that 1002:aab0 device at 02:00.1
is the "bus"? As a result of this behavior, a completely different
device as "Acer DynaVivid Graphics Dock" is showing up on my system as
a result of the "High Definition Audio Bus" after installing AMD
drivers. None of my devices are Acer, and certainly nothing should be
a graphics dock?


vfio-users mailing list
vfio-users at redhat.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/vfio-users/attachments/20160424/ed860304/attachment.htm>

More information about the vfio-users mailing list