Cannot start VM missing strange item...

[Mattias Hedman]

This is the error code 1 for my 300 VM:
kvm: -device vfio-pci,host=0000:42:00.0,id=hostpci0,bus=ich9-pcie-port-1,addr=0x0,x-vga=on: vfio 0000:42:00.0: failed to open /dev/vfio/56: Device or resource busy
start failed: QEMU exited with code 1

failed to open /dev/vfio/56 - say what? What is this?

 

[krikey]

It looks like you're trying to pass through a PCI device to your VM. If so, could it have already been used by the host and therefore not available to the client VM?

What is the device you're trying to pass through?

 

[Mattias Hedman]

It looks like you're trying to pass through a PCI device to your VM. If so, could it have already been used by the host and therefore not available to the client VM?

What is the device you're trying to pass through?

It is a GPU I am trying to pass through, this is the VM that sole access to it. It was working just fine until I had to restart the pve-host.

 

[krikey]

Did you clone the VM that had sole access to the GPU and is that running at all?

Can you confirm that the host isn't using the GPU by seeing whether theres any output to your monitor attached to the GPU?

I've got my rig setup with Proxmox host using the mobo iGPU which is plugged into the HDM port on my monitor. The client (Windows 10) has dedicated access to the GPU which is also plugged into the same monitor via DisplayPort. This is sometimes confusing, especially when Windows 10 goes into sleep and I end up with the PVE command line.

 

[Mattias Hedman]

@krikey No it is not cloned.
It uses a GPU that is connected via PICe inside my server. Drivers for the GPU is installed both on the host and on the VM.

 

[krikey]

Did you follow https://pve.proxmox.com/wiki/Pci_passthrough paying special attention to the "blacklist" section. Im not sure if you need to install the GPU drives on the host as your'e not going to be using it there anyway.

 

[Mattias Hedman]

I have read that, when I installed all the things I followed this guide: https://www.youtube.com/watch?v=TPKWs3OG6tU
But as I said, it worked perfect before a host restart.

 

[krikey]

I'm not going to watch the 30 minute video but as part of the process of enabling IOMMU, you needed to have done a restart (as per the guide at https://pve.proxmox.com/wiki/Pci_passthrough) before the GPU can essentially be handed over to the client.

Presumably you followed this guide and confirmed each step as it's laid out, not just read it?