Method for switching between virtualized and non-virtualized system operation

摘要

A method performed by an embedded system controlled by a CPU and capable of operating as a virtualized system under supervision of a hypervisor or as a non-virtualized system under supervision of an operating system, is provided. The embedded system is executed in a normal mode if no execution of any security critical function is required, where the normal mode execution is performed under supervision of the operating system. If a security critical function execution is required, where protected mode execution is performed under supervision of the hypervisor, the operating system is switching execution of the embedded system from normal mode to protected mode, by handing over the execution of the embedded system from the operating system to the hypervisor. When execution of the security critical function is no longer required by the system is switched from protected mode to normal mode, under supervision of the hypervisor.

主权项

1. In a system comprising an embedded system capable of operating as a virtualized system under supervision of a hypervisor or as a non-virtualized system under supervision of an operating system, a method comprising the steps of:
executing the embedded system in a normal mode, if no execution of any security critical function is required by the embedded system, where the normal mode execution is performed under supervision of the operating system; determining that execution of a security critical function is required by the embedded system; switching, by the operating system, execution of the embedded system from normal mode to protected mode, by handing over the execution of the embedded system from the operating system to the hypervisor, in response to the determination that execution of the security critical function is required by the embedded system, where protected mode execution is performed under supervision of the hypervisor; determining that the execution of the security critical function is no longer required by the embedded system; and switching, under supervision of the hypervisor, the embedded system from protected mode to normal mode, in response to the determination that execution of the security critical function is no longer required by the embedded system.