As system designers are transitioning to the usage of pre-existing software architectural elements to reduce time-to-market and costs, they face challenges in safety-critical applications. Pre-existing software may have been implemented without following any safety and/or quality standard, and its documentation may be incomplete or unclear. As recommended by part 6 of the functional safety standard ISO 26262 (product development at the software level), stringent rules and guidelines must be followed during the implementation of a new software. The qualification of a pre-existing software according to ISO 26262 may hence be very time consuming and expensive if not addressed in a structured way. This work presentsSTPA for Pre-existing Software(STPA-PES), a new software hazardous behavior analysis approach designed to identify criticalities or abnormal conditions in complex pre-existing software to be mitigated with adequate safety measures. The major challenge in such a process consists in the definition of a model that correctly represents the system under analysis when the architectural design of pre-existing software is not available. As a relevant example, the proposed approach is finally applied to dynamic memory allocator (DynMA) in Linux kernel to show how STPA-PES is able to derive safety requirements of this software architectural element.

Dynamic memory allocation is a pivotal feature of modern software systems but has mostly been scarcely used in real-time systems due to the limited time-predictability offered by dynamic memory allocators (DynMAs). While many general-purpose DynMAs have been proposed during the last decades, only a few efforts were devoted to the design of real-time DynMAs capable of providing bounded allocation times. Furthermore, the most notable of them dates back to almost 20 years ago. Motivated by this observation and the significant developments made in the field of general-purpose DynMAs in recent years, this work takes a new look at dynamic memory allocation for real-time systems. After analyzing and comparing modern DynMAs, we discuss how to modify the Mimalloc general-purpose DynMA into RT-Mimalloc, so that more predictable allocation times can be obtained. All the studies and evaluations performed in this work were based on both modern state-of-the-art benchmarks for memory allocation and synthetic workload to assess specific capabilities of the tested DynMAs. The evaluation showed that RT-Mimalloc is capable to improve the longest-observed allocation times of real-time DynMAs proposed in previous work while retaining most of the benefits of modern general-purpose DynMAs in terms of average-case performance.

Next generation cars will increase the passengers’ time for fun and relax, as well as the number of unknown passengers traveling together. A key functionality to improve the users’ experience is that of Temporary Mobile Social Networking (TMSN): where passengers form, for a limited-time, a mobile social group with common interests and activities, using their already available social network accounts. The goal of TMSN is to automatically redesign the users’ profiles and interfaces into a group-wise passengers’ profile and a common interface, by reducing isolation and enabling socialization. In this paper, a TMSN-inspired music selection is proposed and developed via the Spotify music streaming service. Early results are promising and encourage further developments towards the concept of in-car entertainment.