My partially broken OVMF GPU passthrough notes

gistfile1.txt

cmdline:
	hugepages=2048
	intel_iommu=on,igfx_off,pt
	rd-driver-pre=vfio-pci
	vfio-pci.ids=10de:1380,10de:0fbc,1002:ffffffff:ffffffff:ffffffff:00030000:ffff00ff,1002:ffffffff:ffffffff:ffffffff:00040300:ffffffff,10de:ffffffff:ffffffff:ffffffff:00030000:ffff00ff,10de:ffffffff:ffffffff:ffffffff:00040300:ffffffff
	vfio-pci.disable_vga=1 (OVMF way, optional)
	#i915.enable_hd_vgaarb=1 (Legacy way)
	#kvm_intel.emulate_invalid_guest_state=0 (optional)
	#kvm.ignore_msrs=1 (optional)

add these modules to initramfs (/etc/initramfs-tools/modules on debian):
	vfio
	vfio_iommu_type1
	vfio_pci
	vfio_virqfd

ensure early vfio-pci binding: ...

script example:

#!/bin/bash

VDIR=/mnt/hdd/virt
MON=/tmp/qemu-monitor
cd $VDIR

mkfifo $MON.in $MON.out

sudo qemu-system-x86_64 -nodefaults -nodefconfig \
        -monitor pipe:$MON \
        -enable-kvm -m 2048 -cpu host,kvm=off \
        -smp 4,sockets=1,cores=4,threads=1 \
        -drive if=pflash,format=raw,readonly,file=ovmf_code_x64.bin \
        -drive if=pflash,format=raw,file=ovmf_vars_x64.bin \
        -drive file=install.iso,if=none,id=drive-cd-0,format=raw \
        -device ide-cd,drive=drive-cd-0,unit=0,bus=ide.1 \
        -drive
if=ide,id=drive-hd-0,file=drive.img,format=raw,cache=none,aio=native \
        -device vfio-pci,host=01:00.0 -device vfio-pci,host=01:00.1 \
        -vga none -nographic

rm -f $MON.in $MON.out