audio is same IOMMU group as ethernet - how pass through?

[chromium]

So I compared iommu groups with and without pcie_acs_override=downstream,multifunction and they are identical, so it looks like it's unable to split anything on this system.

IOMMU group 0 00:02.0 VGA compatible controller [0300]: Intel Corporation CoffeeLake-S GT2 [UHD Graphics 630] [8086:3e92]
IOMMU group 10 01:00.0 Non-Volatile memory controller [0108]: SK hynix Gold P31/PC711 NVMe Solid State Drive [1c5c:174a]
IOMMU group 1 00:00.0 Host bridge [0600]: Intel Corporation 8th Gen Core Processor Host Bridge/DRAM Registers [8086:3ec2] (rev 07)
IOMMU group 2 00:08.0 System peripheral [0880]: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th/8th Gen Core Processor Gaussian Mixture Model [8086:1911]
IOMMU group 3 00:12.0 Signal processing controller [1180]: Intel Corporation Cannon Lake PCH Thermal Controller [8086:a379] (rev 10)
IOMMU group 4 00:14.0 USB controller [0c03]: Intel Corporation Cannon Lake PCH USB 3.1 xHCI Host Controller [8086:a36d] (rev 10)
IOMMU group 4 00:14.2 RAM memory [0500]: Intel Corporation Cannon Lake PCH Shared SRAM [8086:a36f] (rev 10)
IOMMU group 5 00:15.0 Serial bus controller [0c80]: Intel Corporation Cannon Lake PCH Serial IO I2C Controller #0 [8086:a368] (rev 10)
IOMMU group 6 00:16.0 Communication controller [0780]: Intel Corporation Cannon Lake PCH HECI Controller [8086:a360] (rev 10)
IOMMU group 6 00:16.3 Serial controller [0700]: Intel Corporation Cannon Lake PCH Active Management Technology - SOL [8086:a363] (rev 10)
IOMMU group 7 00:17.0 SATA controller [0106]: Intel Corporation Cannon Lake PCH SATA AHCI Controller [8086:a352] (rev 10)
IOMMU group 8 00:1b.0 PCI bridge [0604]: Intel Corporation Cannon Lake PCH PCI Express Root Port #17 [8086:a340] (rev f0)
IOMMU group 9 00:1f.0 ISA bridge [0601]: Intel Corporation Q370 Chipset LPC/eSPI Controller [8086:a306] (rev 10)
IOMMU group 9 00:1f.3 Audio device [0403]: Intel Corporation Cannon Lake PCH cAVS [8086:a348] (rev 10)
IOMMU group 9 00:1f.4 SMBus [0c05]: Intel Corporation Cannon Lake PCH SMBus Controller [8086:a323] (rev 10)
IOMMU group 9 00:1f.5 Serial bus controller [0c80]: Intel Corporation Cannon Lake PCH SPI Controller [8086:a324] (rev 10)
IOMMU group 9 00:1f.6 Ethernet controller [0200]: Intel Corporation Ethernet Connection (7) I219-LM [8086:15bb] (rev 10)

Identical in both scenarios

 

[MadMurl0c]

@chromium Did you find any fix/workaround? I have the exact same problem. I try to virtualize a HTPC and need to pass through HDMI Video + Audio. Video works fine but since Audio is in the same IOMMU Group with Ethernet my Proxmox host becomes unresponsive once I add the Audio Device to the VM. I thought it would be enough to pass through the GPU but I cannot get any audio output devices that way

 

[paoloc68]

I have the same problem, two GPUs on the same IOMMU group