In paravirtualization, guest operating systems (OSs) are aware of being virtualized. In this approach, the guest operating system kernel is modified to eliminate the need for Binary Translation. While it is possible to modify open source operating systems, such as Linux and OpenBSD, it is not possible to modify “closed” source operating systems such as Microsoft Windows. Paravirtualization is possible in open source operating systems. A full virtualization approach should be adopted for unmodified guest operating systems such as Microsoft Windows.
Xen and KVM are product examples of paravirtualization.