Anthony Shipman wrote:
VT-d is completely unrelated. VT-d is virtualisation support. if you ever want to run kvm or virtualbox or similar you'll need it enabled. [...]
Wikipedia says that VT-d is Intel's idea of an IOMMU. But my BIOS doesn't show it despite what the manual says. There is nothing else in the BIOS resembling an IOMMU or memory hole remapping.
AIUI, 1. Intel's CPU virtualization is called "VT-x". You need it to modprobe kvm. 2. Intel's I/O virtualization is called "VT-d". According to #kvm, it is ONLY useful if you assign an ENTIRE disk (as in sata0, not an arbitrary block device) to a VM. Since I don't do that (I use mdadm and LVM), that's where I lost interest in VT-d. 3. Strictly, VT-x is CPU virtualization for x86-64. There is a separate VT-i or something for itanium, but nobody cares.