MCS-IOV: Real-Time I/O Virtualization for Mixed-Criticality Systems

Abstract

In mixed-criticality systems, timely handling of I/O is a key for the system being successfully implemented and functioning appropriately. The criticality levels of functions and sometimes the whole system are often dependent on the state of the I/O. An I/O system for a MCS must provide simultaneously isolation/separation, performance/efficiency and timingpredictability, as well as being able to manage I/O resource in an adaptive manner to facilitate efficient yet safe resource sharing among components of different criticality levels. Existing approaches cannot achieve all of these requirements simultaneously. This paper presents a MCS I/O management framework, termed MCS-IOV. MCS-IOV is based on hardware assisted virtualisation, which provides temporal and spatial isolation and prohibits fault propagation with small extra overhead in performance. MCS-IOV extends a real-time I/O virtualisation system, by supporting the concept of mixed criticalities and customised interfaces for schedulers, which offers good timing-preditability. MCS-IOV supports I/O driven criticality mode switch (the mode switch can be triggered by detection of unexpected I/O behaviors, e.g., a higher I/O utilization than expected) and timely I/O resource reconfiguration up on that. Finally, We evaluated and demonstrate MCS-IOV in different aspects.

HSP-V: Hypervisor-Less Static Partitioning for RISC-V COTS Platforms

“…Similarly, Arm TrustZone offers hardware-based access control by enabling a processor to run in two isolated execution environments, i.e., the secure and non-secure world. TrustZone is widely used in mobile devices and ARM-based servers [25], hosting secure kernels such as Trustonic 3 , Qualcomm's QSEE 4 , and Linaro's OP-TEE 5 , ensuring the protection of securitycritical data, and facilitating the deployment of various TAs with distinct functionalities.…”

“…C yber-physical systems have evolved significantly in the past few decades [1], transitioning from single-purpose devices with limited communications and simple interfaces to power-and compute-hungry general-purpose systems with multiple functionalities and complex interactions [2]. To meet the demands for reduced size, weight, power, and cost (SWaP-C), there has been a paradigm shift towards the deployment of mixed-criticality systems (MCS), which integrate and consolidate different applications with distinct levels of criticality into a single hardware platform [3]- [5]. This approach requires spatial, temporal, and fault isolation among all subsystems, ensuring that subsystems with lowercriticality do not compromise the timing, functionality, or performance of the safety-critical ones.…”

Self-secured devices: High performance and secure I/O access in TrustZone-based systems

“…Self-virtualized devices were designed, from the ground-up, for servers and cloud requirements and materialized in the SRIOV for PCIe [23]. Preeminent solutions for IO virtualization for (embedded) mixed-criticality systems include BlueIO [30] and MCS-IOV [31].…”