pve-passthrough

Turn on IOMMU
/etc/default/grub
add "intel_iommu=on, iommu=pt" in GRUB_CMDLINE_LINUX_DEFAULT
update-grub
For spoto-pve-hackintosh use this command
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt pcie_acs_override=downstream,multifunction nofb textonly nomodeset video=efifb:off"

For hvse-pve-hackintosh, use
dmesg | grep -e DMAR -e IOMMU
to check for errors

Interrupt remapping

echo "options vfio_iommu_type1 allow_unsafe_interrupts=1" > /etc/modprobe.d/iommu_unsafe_interrupts.conf
echo "options kvm ignore_msrs=1" > /etc/modprobe.d/kvm.conf

Add modules in /etc/modules

vfio
vfio_iommu_type1
vfio_pci
vfio_virqfd

Check the ID
lspci -n -s 01:00
find the ID (01:00) with lspci -v
echo "options vfio-pci ids=10de:1b81,10de:10f0 disable_vga=1"> /etc/modprobe.d/vfio.conf
enter the ID (all of it in ids=)
update-initramfs -u
reboot the host

Prevent PVE host from using the GPU

echo "blacklist radeon" >> /etc/modprobe.d/blacklist.conf 
echo "blacklist nouveau" >> /etc/modprobe.d/blacklist.conf 
echo "blacklist nvidia" >> /etc/modprobe.d/blacklist.conf

When using PCI passthrough, all the RAM is pre-allocated, no ballooning.

When choosing all function when selecting a GPU for passthrough, all the subgroup of a devices with function (eg. both VGA and audio for a GPU)

To start a system with iGPU only when dGPU is plugged in, enable iGPU Multi-Monitor and Primary Display to iGPU in the BIOS.

If GPU require a rom file, edit the configuration of VM
hostpci0: ...., romfile=file.rom file.rom is placed in /usr/share/kvm