--- wikisrc/ports/xen/howto.mdwn	2016/12/20 13:16:43	1.115
+++ wikisrc/ports/xen/howto.mdwn	2016/12/20 14:52:43	1.116
@@ -30,9 +30,13 @@ style is less efficient but can run unmo
 Generally any amd64 machine will work with Xen and PV guests.  In
 theory i386 computers without amd64 support can be used for Xen <=
 4.2, but we have no recent reports of this working (this is a hint).
-For HVM guests, the VT or VMX CPU feature (Intel) or SVM/HVM/VT
-(amd64) is needed; "cpuctl identify 0" will show this.  TODO: Clean up
-and check the above features.
+For HVM guests, hardware support is needed, but it is common on recent
+machines.  For Intel CPUs, one needs the VT-x extension, shown in
+"cpuctl identify 0" as VMX.  For AMD CPus, one needs the AMD-V
+extensions, shown in "cpuctl identify 0" as SVM.  There are further
+features for IOMMU virtualization, Intel's VT-d and AMD's AMD-Vi.
+TODO: Explain whether Xen on NetBSD makes use of these features.
+TODO: Review by someone who really understands this.
 
 At boot, the dom0 kernel is loaded as a module with Xen as the kernel.
 The dom0 can start one or more domUs.  (Booting is explained in detail