Couldn't Add vGPU to VM use vendor-specific VFIO framework

Hello everyone,

I tried to use L40s to add a vGPU to VM on KVM in Ubuntu 22.04, but it shows “Unmanaged PCI device [my vGPU pci] must be manually detached from the host”.

My device supports SR-IOV and seems to use the vendor-specific VFIO framework.
Therefore, I followed the steps in this document (Chapter 2.10) to setting vGPU and use virsh to add it.
When I tried to start VM, it failed and show error above.

Did I do something wrong or is there anything I haven’t configured?
Please help me, thanks.