Hardware passthrough of onboard sound card fails

[tshorts]

I'm trying my first passthrough for a "guest gaming PC" on my unraid server. 

The Windows VM boots when I only have the NVIDIA Graphics card, and NVIDIA Sound card enabled.

But when I try to passthrough a secondary soundcard, the one integrated on the motherboard, which is the one that will be used, the boot fails.

 

IOMMU group 10:	[8086:a2c8] 00:1f.0 ISA bridge: Intel Corporation 200 Series PCH LPC Controller (B250)
[8086:a2a1] 00:1f.2 Memory controller: Intel Corporation 200 Series/Z370 Chipset Family Power Management Controller
[8086:a2f0] 00:1f.3 Audio device: Intel Corporation 200 Series PCH HD Audio
[8086:a2a3] 00:1f.4 SMBus: Intel Corporation 200 Series/Z370 Chipset Family SMBus Controller

 

 

It's 00.1f.3 I try to add.

 

I get this error:

 

Syslog:

Feb 14 02:51:16 Tserve kernel: vfio-pci 0000:01:00.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=io+mem:owns=none
Feb 14 02:51:16 Tserve kernel: br0: port 2(vnet0) entered blocking state
Feb 14 02:51:16 Tserve kernel: br0: port 2(vnet0) entered disabled state
Feb 14 02:51:16 Tserve kernel: device vnet0 entered promiscuous mode
Feb 14 02:51:16 Tserve kernel: br0: port 2(vnet0) entered blocking state
Feb 14 02:51:16 Tserve kernel: br0: port 2(vnet0) entered forwarding state
Feb 14 02:51:17 Tserve kernel: vfio_ecap_init: 0000:01:00.0 hiding ecap 0x19@0x900
Feb 14 02:51:17 Tserve kernel: br0: port 2(vnet0) entered disabled state
Feb 14 02:51:17 Tserve kernel: device vnet0 left promiscuous mode
Feb 14 02:51:17 Tserve kernel: br0: port 2(vnet0) entered disabled state
Feb 14 02:51:18 Tserve kernel: vfio-pci 0000:01:00.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=io+mem:owns=none

 

 

 

 

PCIe ACS override is set to Both and split the GPU to different IOMMU groups. But not for the Intel group. 

 

I've tried "VFIO allow unsafe interrupts" both No and Yes, but I get the same error. 

I can't find any way to add the other things in that IOMMU group to the VM. 

 

Is there a way to get the Intel/motherboard soundcard to work, or is it impossible due to the structure of the motherboard? 

 

 

 

Edited February 14, 2021 by tshorts

[Squid]

1 hour ago, tshorts said:

But not for the Intel group. 

If ACS can't break apart the integrated soundcard from other devices, then there's not much that you can do.