ref>
Note to developers: Xen 4.0 can be built on RHEL5 / CentOS 5,
but if you want to modify the sources before building, then you need to have a newer version of "flex" than what's included in the EL5 distributions! For more information please see http://lists.xensource.com/archives/html/xen-devel/2010-03/msg00180.html and http://xenbits.xensource.com/xen-4.0-testing.hg?rev/3138b3885999
*
Hyper-V
VT-x
VT-c(?)
VT-i
VT-d
AMD-V
AMD-Vi
IOMMU（input/output memory management unit）-890FX
