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Car manufacturers relentlessly replace or augment the functionality of mechanical subsystems with electronic components. Most such subsystems (e.g., steer-by-wire) are safety related, hence, subject to regulation. ISO-26262, the dominant standard for road vehicles, regards software faults as systematic , while differentiating hardware faults between systematic and random . The analysis of systematic faults entails rigorous processes and qualitative considerations. The increasing complexity of modern on-board computers, however, questions the very notion of treating the violation of execution-time envelopes for software programs as a systematic fault. Modern hardware in fact reduces the user's ability to delve deep enough into the fabric of hardware–software interaction to gage its extent of contribution to the worst-case execution time (WCET). Changing the nature of the WCET-analysis problem may help address that challenge effectively. To this end, we propose a solution that should allow ISO-26262 to quantify the likelihood of execution-time exceedance events, relating it to target failure metrics employed in support of certification arguments, similarly to random faults in hardware. To this end, we inject randomization in the timing behavior of the computer hardware to relieve the user from the need to control hard-to-reach low-level parts, and use measurement-based probabilistic timing analysis to quantify, constructively, the failure rates resulting from the likelihood of execution-time exceedance events., This work was supported in part by the Spanish Ministry of Science and Innovation under Grant TIN2015-65316-P, in part by the HiPEAC Network of Excellence, and in part by the CONCERTO project (ARTEMIS-JU Grant 333053). The work of J. Abella was supported in part by the Ministry of Economy and Competitiveness under Ramon y Cajal postdoctoral fellowship number RYC-2013-14717. The work of C. Hernández was supported in part by the Spanish Ministry of Economy and Competitiveness and in part by FEDER funds through Grant TIN2014-60404-JIN. The work of E. Mezzetti was supported in part by the Spanish Ministry of Economy and Competitiveness under Juan de la Cierva-Incorporación Postdoctoral Fellowship number IJCI-2016-27396., Peer Reviewed, Postprint (author's final draft)

The use of Commercial Off-The-Shelf (COTS) multicores in real-time industry is on the rise due to multicores' potential performance increase and energy reduction. Yet, the unpredictable impact on timing of contention in shared hardware resources challenges certification. Furthermore, most safety certification standards target single-core architectures and do not provide explicit guidance for multicore processors. Recently, however, CAST-32A has been presented providing guidance for software planning, development and verification in multicores. In this paper, from a theoretical level, we provide a detailed review of CAST-32A objectives and the difficulty of reaching them under current COTS multicore design trends; at experimental level, we assess the difficulties of the application of CAST-32A to a real multicore processor, the NXP P4080., This work has been partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under grant TIN2015-65316-P and the HiPEAC Network of Excellence. Jaume Abella has been partially supported by the MINECO under Ramon y Cajal grant RYC-2013-14717., Peer Reviewed, Postprint (author's final draft)

The use of increasingly complex hardware and software platforms in response to the ever rising performance demands of modern real-time systems complicates the verification and validation of their timing behaviour, which form a time-and-effort-intensive step of system qualification or certification. In this paper we relate the current state of practice in measurement-based timing analysis, the predominant choice for industrial developers, to the proceedings of the PROXIMA (Probabilistic real-time control of mixed-criticality multicore systems) project in that very field. We recall the difficulties that the shift towards more complex computing platforms causes in that regard. Then we discuss the probabilistic approach proposed by PROXIMA to overcome some of those limitations. We present the main principles behind the PROXIMA approach as well as the changes it requires at hardware or software level underneath the application. We also present the current status of the project against its overall goals, and highlight some of the principal confidence-building results achieved so far., The research leading to these results has received funding from the European Community’s Seventh Framework Programme [FP7/2007-2013] under the PROXIMA Project (grant agreement 611085). Carles Hern´andez is jointly funded by the Spanish Ministry of Economy and Competitiveness (MINECO) and FEDER funds through grant TIN2014-60404-JIN. Jaume Abella has been partially supported by the MINECO under Ramon y Cajal postdoctoral fellowship number RYC-2013-14717., Peer Reviewed, Postprint (author's final draft)