Need Assistance with amdgpu and X

From hours of trawling through /r/vfio and various guides, I'm stuck trying to get my second GPU to passthrough

OS: Ubuntu 18,04

Kernel: 4.17.5-041705-generic

GPUs: Dual AMD RX Vega 64

0c:00.0 VGA compatible controller \[0300\]: Advanced Micro Devices, Inc. \[AMD/ATI\] Vega 10 XT \[Radeon RX Vega 64\] \[1002:687f\] (rev c1)

Subsystem: Advanced Micro Devices, Inc. \[AMD/ATI\] Vega 10 XT \[Radeon RX Vega 64\] \[1002:0b36\]

Kernel driver in use: amdgpu

Kernel modules: amdgpu

0c:00.1 Audio device \[0403\]: Advanced Micro Devices, Inc. \[AMD/ATI\] Device \[1002:aaf8\]

Subsystem: Advanced Micro Devices, Inc. \[AMD/ATI\] Device \[1002:aaf8\]

Kernel driver in use: vfio-pci

Kernel modules: snd\_hda\_intel

Above is my target GPU to passthrough. My host one is...

44:00.0 VGA compatible controller \[0300\]: Advanced Micro Devices, Inc. \[AMD/ATI\] Vega 10 XT \[Radeon RX Vega 64\] \[1002:687f\] (rev c1)

Subsystem: Advanced Micro Devices, Inc. \[AMD/ATI\] Vega 10 XT \[Radeon RX Vega 64\] \[1002:6b76\]

Kernel driver in use: amdgpu

Kernel modules: amdgpu

44:00.1 Audio device \[0403\]: Advanced Micro Devices, Inc. \[AMD/ATI\] Device \[1002:aaf8\]

Subsystem: Advanced Micro Devices, Inc. \[AMD/ATI\] Device \[1002:aaf8\]

Kernel driver in use: vfio-pci

Kernel modules: snd\_hda\_intel

Identical devices, which really complicates the matter. I saw posts about setting in modules with vfio\_pci loading before amdgpu, but that doesn't seem to be successful. What am I doing wrong?

Contents of module:

install vfio\_pci /sbin/vfio-pci-override.sh

softdep amdgpu pre: vfio vfio\_pci

vfio

vfio\_iommu\_type1

vfio\_virqfd

options vfio\_pci ids=1002:687f,1002:0b36

vfio\_pci ids=1002:687f,1002:0b36

vfio\_pci

I 755'd the script to no avail. I even had it in /usr/bin/ based on another guide without success. I'm rocking a TR1950X and as such do not have an iGPU to blacklist amdgpu. I managed to change Xorg to set "AutoAddGPU" to "off" which allowed me to unbind the GPU before without freezing, but I couldn't use the driver\_override on the GPU to passthrough vfio. It'll take it, nothing happens.

I tried to unbind the driver, but I get access denied. Looking at the contents of the folder, unbind is missing on the list of files in /sys/bus/pci/devices/0000:0c:00.0/. I hadn't erased any files.

I feel like this is almost a repost of sorts with all the confusion following this, but I've looked through a lot of these and I'm pretty much out of options.