Abstract: Methods, systems, and computer program products for direct assignment of physical devices to confidential virtual machines (VMs). At a first guest privilege context of a guest partition, a direct assignment of a physical device associated with a host computer system to the guest partition is identified. The guest partition includes the first guest privilege context and a second guest privilege context, which is restricted from accessing memory associated with the first guest privilege context. The guest partition corresponds to a confidential VM, such that a memory region associated with the guest partition is inaccessible to a host operating system. It is determined, based on a policy, that the physical device is allowed to be directly assigned to the guest partition. Communication between the physical device and the second guest privilege context is permitted, such as by exposing the physical device on a virtual bus and/or forwarding an interrupt.

Abstract: A system and method for controlling Radio Frequency (RF) devices. A serial RF control bus (106) provides a half-duplex serial communication interconnect path between a bus master (108) and one or more bus slaves (110). The bus master is coupled to a processor (102), and each bus slave is coupled to an RF device (104) that operates without a free-running clock. The processor controls the RF devices by sending and receiving messages over the RF control bus. The bus master and bus slaves format these messages for transmission across the RF control bus. The RF control bus includes a bi-directional data line (120), a first clock line (124), and a second clock line (122). The first clock line is asserted by the bus master when transmitting serial data to and receiving serial data from the RF slaves via the data line. The second clock line is asserted by the RF slaves when transmitting serial data to the bus master via the data line.