I have been running GPU passthrough with UEFI and KVM on Linux for the best part of a decade (XP x64, now Windows 10 x64), and that has been working great, but recently I tried to get it working with Windows 10 IA32, and my Nvidia GPU always shows code 43 error. I applied all the VM hiding I use on x64, and in fact the libvirt domain xml is identical, with the only exception being the use of IA32 OVMF image instead of the X64 one and the OS in the VM. Same host, same GPU.
Does anyone know if there are any known problems and workarounds for getting this to work with 32-bit guests? The OS boots fine, but it refuses to work with my GTX 1070. If I completely uninstall the driver and delete it, it eventually tries the Microsoft Basic Display Adapter, but even that shows code 43. So there seems to be something genuinely broken in the 32-bit path, and given the only differences are the OVMF firmware and the OS, it is obviously something between those two that is causing the problem (for once I don't think it is the Nvidia driver).
Has anyone managed to get 32-bit UEFO Windows working with GPU passthrough?