What is the HVM?
The HVM is the hardware virtual machine capability, which allows operating systems that are not virtualization-aware to operate on top of a virtualization platform such as xVM Server. To make an operating system run on the Xen hypervisor, it was necessary to make changes to the guest. This was not allowed for some OSs such as Microsoft. As a solution, the Xen hypervisor leverages the facilities of AMD-V and Intel VT chips together with the HVM code to allow guests to run unchanged. This approach has also been used for the Solaris 10 Operating System unmodified.
