Comment 3 for bug 1826422

This seems related to INTx (legacy) interrupt mode, which NVIDIA GeForce will use by default. Using regedit in a Windows VM or adjusting nvidia.ko module parameters of a Linux VM can enable the driver to use MSI, which seems unaffected. We also have the vfio-pci device option x-no-kvm-intx=on, which is probably a good compliment to configuring the driver to use MSI until we get this figured out, as the Windows driver likes to occasional switch MSI off, which would leave you in a bad state. Routing INTx through QEMU would be a performance regression though, so while a workaround, having it routed through QEMU and not using MSI, is not a great combination.