Analysis of information sources in references of the Wikipedia article "Virtual 8086 mode" in English language version.
To facilitate virtualization of real mode, the VMRUN instruction may legally load a guest CR0 value with PE = 0 but PG = 1. Likewise, the RSM instruction is permitted to return to paged real mode. This processor mode behaves in every way like real mode, with the exception that paging is applied. The intent is that the VMM run the guest in paged-real mode at CPL0, and with page faults intercepted. The VMM is responsible for setting up a shadow page table that maps guest physical memory to the appropriate system physical addresses. The behavior of running a guest in paged real mode without intercepting page faults to the VMM is undefined.
a VM entry is allowed only to guests with paging enabled that are in protected mode or in virtual-8086 mode. Guest execution in other processor operating modes need to be specially handled by the VMM; see also CS 686: Special Topic: Intel EM64T and VT Extensions (Spring 2007), lesson 24 how to do this from Linux (not that the code is pretty dated, so might not work as-is with current kernels) more up-to-date code can be found here. Also beware that this sample code is more complicated than strictly booting the logical processor in virtual 8086 mode; its ultimate goal is make some real-mode BIOS calls.
A list of Intel processors that support VT-x but not EPT
a VM entry is allowed only to guests with paging enabled that are in protected mode or in virtual-8086 mode. Guest execution in other processor operating modes need to be specially handled by the VMM; see also CS 686: Special Topic: Intel EM64T and VT Extensions (Spring 2007), lesson 24 how to do this from Linux (not that the code is pretty dated, so might not work as-is with current kernels) more up-to-date code can be found here. Also beware that this sample code is more complicated than strictly booting the logical processor in virtual 8086 mode; its ultimate goal is make some real-mode BIOS calls.
{{cite journal}}: Cite journal requires |journal= (help)a VM entry is allowed only to guests with paging enabled that are in protected mode or in virtual-8086 mode. Guest execution in other processor operating modes need to be specially handled by the VMM; see also CS 686: Special Topic: Intel EM64T and VT Extensions (Spring 2007), lesson 24 how to do this from Linux (not that the code is pretty dated, so might not work as-is with current kernels) more up-to-date code can be found here. Also beware that this sample code is more complicated than strictly booting the logical processor in virtual 8086 mode; its ultimate goal is make some real-mode BIOS calls.
a VM entry is allowed only to guests with paging enabled that are in protected mode or in virtual-8086 mode. Guest execution in other processor operating modes need to be specially handled by the VMM; see also CS 686: Special Topic: Intel EM64T and VT Extensions (Spring 2007), lesson 24 how to do this from Linux (not that the code is pretty dated, so might not work as-is with current kernels) more up-to-date code can be found here. Also beware that this sample code is more complicated than strictly booting the logical processor in virtual 8086 mode; its ultimate goal is make some real-mode BIOS calls.
A list of Intel processors that support VT-x but not EPT