Formal Specification for Building Robust Real-time Microkernel

Manuel Rodríguez, Jean-Charles Fabre, Jean Arlat

 

Abstract

This paper presents a method based on formal specifications for building robust real-time microkernels.
Temporal logic is used to specih the functional and temporal properties of real-time kernels with respect to
their main services (e.g., scheduling, time, synchronization, and clock interrupts). As an example of
a synchronization mechanism, the specification of the Priority Ceiling Protocol is provided. The objective is to
verify kernel properties at runtime in order to improve the internal kernel’s detection mechanisms and
complement their weaknesses. The core of this paper is a complete description of the temporal logic formulas corresponding to real-time kernel specifications. The formulas developed in this paper are the basis for the implementation of fault containment wrappers. The combination of COTS microkernels and wrappers leak to the notion of robust microkernels. The provided case study illustrates the approach on top of an instance of the Chorus microkernel.

Keywords: Formal specification, operating system kernels, real-time systems, synchronisation, temporal logic.