[ubuntu] VT-d in KVM

Hello,
regarding "How to assign devices with VT-d in KVM", i`m trying to modifying kernel config.
So after going to -> /usr/src/linux-headers-3.x.x-x and make menuconfig, cannot find
"Bus options (PCI etc.)" -> "Support for DMA Remapping Devices"
"Bus options (PCI etc.)" -> "Enable DMA Remapping Devices"
"Bus options (PCI etc.)" -> "PCI Stub driver"
They just missing in menu options.
Where I'm wrong?


Thank you in advance!