Guide: bind devices to vfio-pci for easy passthrough to VMs
TL;DR - skip to the second post if you just want to know how to convert from legacy PCI stubbing via Syslinux to the new point and click method in Unraid 6.9
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At times you will want to "hide" devices from Unraid so that they can be passed through to a VM.
Unraid Prior to 6.7
In the past (pre Unraid 6.7) we would stub the device by adding a Vendor:Device code to the vfio-pci.ids parameter in Syslinux, something like this:
append vfio-pci.ids=8086:1533
This worked
I've enabled SR-IOV on a network adapter via modprobe:
/boot/config/modprobe.d/mlx4_core.conf
options mlx4_core num_vfs=4
This creates four Virtual Function devices that can be assigned to multiple virtual machines for direct hardware access (without requiring a dedicated NIC)
This also makes them available to vfio-pci passthrough function:
However this fails
Loading config from /boot/config/vfio-pci.cfg
BIND=0000:03:00.1|15b3:10