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Hazard Analysis Application to Complex Software (Video)

By Blog, Workshop

The Spring ELISA Workshop, which took place on April 5-7 virtually, had more than 130 global registrants that learned more about the various working groups, hot topics related to enabling linux in safety applications and networked with ambassadors. If you missed the workshop, you can check out the materials here or subscribe to the new ELISA Youtube Channel and add these sessions to your watch list.

In April, Raffaele Giannessi, Industrial PhD, and Fabrizio Tronci, Functional Safety Manager and Alessandro Biasci, Project Manager at Huawei, presented a session titled, “Hazard Analysis Application to Complex Software.” In this talk, they showcase the methodology to apply STPA to software non-physical system and application of case study on dynamic memory allocation.

Watch the video below.

If you are interested in learning more about the ELISA Project, please join us at one of the September events:

  • ELISA Summit, a virtual conference happening on September 7-8 . ELISA ambassadors and leaders will offer an introductory overview of the project, more in-depth technical content, emerging trends, and hot topics related to open source software in safety-critical applications. Register to attend at no cost here: https://events.linuxfoundation.org/elisa-summit/register/.
  • ELISA Forum, in-person in Dublin, Ireland on September 12. This is a co-located event with Open Source Summit Europe. ELISA Ambassadors and leaders will offer an overview of the project, the activities of the various working groups (WGs) and how the WGs interact and work together to tackle the challenges in advancing open source in safety-critical systems and bridge the gap between functional safety and Linux kernel development velocity. There will also be in-depth updates for the System-Theoretic Process Analysis (STPA) methodology to a sample use case and a Q&A session. Pre-registration is required. To register for ELISA Forum, add it to your Open Source Summit Europe registration.

Integrity of the Safety Application Address Space (video)

By Blog, Workshop

The Spring ELISA Workshop, which took place on April 5-7 virtually, had more than 130 global registrants that learned more about the various working groups, hot topics related to enabling linux in safety applications and networked with ambassadors. If you missed the workshop, you can check out the materials here or subscribe to the new ELISA Youtube Channel and add these sessions to your watch list.

Red Hat’s Christoffer Hall-Federiksen, Senior Software Engineer, and Gabriele Paoloni, Senior Principal Software Engineer and Chair of the ELISA Project Governing Board, presented a session titled, “Integrity of the Safety Application Address Space.”

In this video, you’ll get an overview  of the address space descriptors and critical Linux Kernel code involved along different scenarios (process creation, memory allocation, context switch, etc.), safety goals and an interactive discussion on the next steps. 

Watch the video below.

Introduction to ELISA (Video)

By Blog, Working Group, Workshop

The Spring ELISA Workshop, which took place on April 5-7 virtually, had more than 130 global registrants that learned more about the various working groups, hot topics related to enabling linux in safety applications and networked with ambassadors. If you missed the workshop, you can check out the materials here or subscribe to the ELISA Youtube Channel and add these sessions to your watch list.

At the workshop, Shuah Khan, Chair of the ELISA Technical Steering Committee (TSC) and Kernel Maintainer and Linux Fellow at the Linux Foundation, joined Kate Stewart, ELISA TSC member and co-chair of the Medical Devices Working Group, to kick off the workshop with an introduction to the ELISA Project.

You can view the video below, which is intended for new community members interested in the project and those who aren’t regular participants in the working groups.

We invite you to join a working group to learn more! Click here to check out the working groups and subscribe to their mailing lists and calendars to join meetings.

Lund Linux Con (Video)

By Ambassadors, Blog

Recently, Philipp Ahmann, an ELISA Ambassador and member of the Technical Steering Committee and Technical Business Development Manager at Bosch, had the chance to speak at the Lund Linux Con about the technical strategy of the ELISA Project, the established work groups as well as the work of the Automotive Working Group.

The Lund Linux Con is a Linux Kernel focused conference in the south of Sweden, typically taking place in May every year. More than 100 participants attended the in person event sponsored by Axis Communications, Western Digital and Volvo Cars to meet and exchange about various Linux Kernel related topics. You can watch Philipp’s presentation below or check out his slides here:

If you’re like to learn more or watch other sessions from the conference, you can view the Youtube Playlist here: https://www.youtube.com/playlist?list=PLTIKt9flsc089GmCeR10mJLhqHbSC6mpi

#Lund #opensource #linuxkernel #functionalsafety #Linux

ELISA’s New Systems Working Group

By Blog, Working Group

Written Philipp Ahmann, ELISA Ambassador and TSC member and Business Development Manager at Robert Bosch GmbH

Many projects share architectural elements, including container technologies, RTOS requirements, or virtualization, but safety concerns mainly touch single-point elements of such a system rather than sticking everything together. This construction of full system architectures is created by distributors or within companies towards a product. Due to their complexity, these systems utilize the work results of various related projects, either open source or proprietary. 

As a result of these recent discussions with industry partners and the open source software (OSS) community, the ELISA Technical Steering Committee (TSC) approved the formation of the Systems Work Group in June 2022.

Although the use of these systems heavily differs, their system architecture elements are repeating. As mentioned, the embedded systems world often ends up with a heterogeneous architecture mixed with RTOS and Linux, virtualization and containers. This is true for medical, industrial, automotive and other industries. These systems have to fulfill certain compliance requirements, including a proper Software Bill of Material (SBOM). It is needed to tailor them for various product lines, to enable a quick project start, reduce maintenance and training efforts and ensure faster product ramp ups. Lastly, these systems typically connect with cloud services for features like monitoring, over the air update, or feature extensions, to increase their maintenance time and to architect higher care for safety as well as dependability, reliability and safety. 

Working Groups, Project interaction and Architecture

The Systems WG explicitly encourages the collaboration of companies and OSS projects to develop a reference system as a workbench. It will target a community, which either also works toward enabling safety use cases with open source software or which plans to make use of open source mixed-criticality system elements as a base for their product lines. 

Currently, the ELISA project already interacts with following community projects:

Taking these puzzle pieces from different projects and bringing them together in a reproducible showcase with goals such as proper SBOM generation is not established in any other open source project so far. There is a lack of an umbrella work group within the extended embedded and edge domain, which provides a reference architecture and a reproducible, dependable system to serve as a blueprint to explore new use cases, functions, or modules. It goes well in line with the recent trend toward software defined vehicles and the first steps into software defined industries, but is not limited to this.

Although the reference architecture may include elements like hypervisors or containers, which have explicitly not been part of ELISA so far, it should enable other working groups to showcase their work on process, features, and tooling with the implementation of a reference system. It can also create ideas and show potential risks or hazards due to a better system understanding; a systems-based understanding of an architecture later on used in a similar way in real world products.

As an important remark, the working group starts with a reference system fully based on “as- is” open source technology. Only a few of the elements contained in the reference system have been developed with considerable safety in mind. This means the created system will act as an example and stimulus environment for mixed criticality Linux based use cases, but is not at all safe or certifiable. 

Instead, it should enable users to exchange certain elements like the container technology, RTOS, or hypervisor technology. This will require a modular design, good documentation and a way to reproduce the system with easy to follow steps.

Next steps and Beyond

The starting point for the reference system is based on the work Stefano Stabelini presented during the Open Source Summit North America, hosted in Austin, TX, June 21-24, called “Static Partitioning with Xen, LinuxRT, and Zephyr: A Concrete End-to-end Example”. As a next step, the system architecture presented in this tutorial will be further extended by adding the Yocto Project as build tooling for all system elements and enhancing the base Linux operating system by adding Automotive Grade Linux towards the end of this year. A full SBOM shall be generated as well. 

Through early 2023, it is planned to extend the system to a physical hardware next to the existing QEMU image, and to also to add container technology, along with cloud connections represented. By doing so, it is possible that a Debian-based Linux may be used as a guest VM or within a container to pick up a wider community.

The work will be documented in a way that showcases why and how the system is configured as it is, while the underlying tooling will enable reproducibility by a few steps as checkout, build and deploy.

Summary

Along with proper documentation on tailoring and reproduction of the showcase, the reference system can serve as a workbench to challenge concepts and implementations from ELISA and other open source projects. It can be used as a quick start to test new ideas during proofs of concept and to let others easily experience achievements of the ELISA project working groups dealing with Linux features, tooling, architecture and more. It is there to foster collaboration of a wide range of open source projects and enables learning from real world scenarios close to later product line architectures. 

Join us

The new Systems WG hosts weekly meetings on Mondays  at 15:00 UTC (8 am PT/11 am ET). To receive the meeting invitation (and working group posts), simply subscribe to the mailing list. The meeting invitation will be sent to you after subscription. Also feel free to reach out to one of the ELISA ambassadors to learn about further ELISA activities.

What is a page table and why should we care about it?(Video)

By Blog, Seminar Series

In March, the ELISA Project launched the Monthly Seminar Series, which focuses on hot topics related to ELISA and its mission. Presenters are members, contributors and thought leaders from the ELISA Project and surrounding communities.

For June, Khalid Aziz, Senior Software Engineer from Oracle, gave a presentation titled, “What is a page table and why should we care about it?” Physical memory on a computer is a shared resource. Kernel allocates and reclaims this shared resource to ensure all workloads on a system have adequate resources to complete their tasks. Accurate management of physical memory assignment is required for fairness and data safety. This is the task of Memory Management subsystem in the Linux kernel. We will discuss how the Memory Management subsystem assigns and tracks physical memory, how it ensures isolation between unrelated workloads and how it enables sharing of data in memory for workloads that need it. We will discuss the management overhead associated with isolation and dive deeper into  specific approaches on managing overhead for effective sharing.

The March seminar focused on the Real-time Linux Analysis Toolset. ELISA community member Daniel Bristot De Oliveira, Senior Principal Software Engineering at Red Hat, presented the tools provided by rtla. You can find out more or watch the video here.

Mixed-Criticality Processing on Linux (Video)

By Blog, Workshop

The Spring ELISA Workshop, which took place on April 5-7 virtually, had more than 130 global registrants that learned more about the various working groups, hot topics related to enabling linux in safety applications and networked with ambassadors. If you missed the workshop, you can check out the materials here or subscribe to the new ELISA Youtube Channel and add these sessions to your watch list.

Christopher Temple, Lead Safety & Reliability Systems Architect at Arm Germany GmbH, and Paul Albertella, ELISA Project TSC member, Chair for Open Source Engineering Process Working Group and Consultant at Codethink, presented a session, “Mixed-Criticality Processing on Linux.”

Check out the video that features the presentation and community discussion about how to create a common understanding of mixed-criticality processing on Linux and the related problems, collect and discuss alternatives for addressing the problems. 

In the video, you’ll see there is good engagement from existing ELISA participants and new ones, and the group ended with a clearer understanding of the challenges faced when safety functions co-exist on a system with non-safety functions, and with other safety functions. There was a broad consensus about how ELISA might provide useful guidance for how to tackle some of these, by describing design patterns for systems that include Linux, rather than focussing on what Linux needs in order to be ‘safe’.

Safety Monitors Inside the Kernel (Video)

By Blog, Workshop

The Spring ELISA Workshop, which took place on April 5-7 virtually, had more than 130 global registrants that learned more about the various working groups, hot topics related to enabling linux in safety applications and networked with ambassadors. If you missed the workshop, you can check out the materials here or subscribe to the new ELISA Youtube Channel and add these sessions to your watch list.

Gabriele Paoloni, ELISA Project Governing Board Chair and Senior Principal Software Engineer at Red Hat, and Daniel Bristot, Senior Principal SW Engineer at Red Hat, gave a presentation at the Spring ELISA Workshop titled, “Safety Monitors Inside the Kernel.”

The recently proposed “Runtime Verification Monitor” framework, which can be found here, has the capability of monitoring the Kernel Drivers / Subsystems to behave as expected and to protect them against interference from within the Kernel itself. The video will explain how the RVM framework works with a specific focus on the Watchdog Monitor that has been proposed in the patchset and how it can support a functional safety claim. Watch it here:

Software Supply Chain Integrity Transparency & Trustworthiness and Related Community Efforts (Video)

By Blog, Workshop

The Spring ELISA Workshop, which took place on April 5-7 virtually, had more than 130 global registrants that learned more about the various working groups, hot topics related to enabling linux in safety applications and networked with ambassadors. If you missed the workshop, you can check out the materials here or subscribe to the new ELISA Youtube Channel and add these sessions to your watch list.

For the first-time ever, the ELISA Project featured a keynote presentation. Robert (Bob) Martin, Senior Principal Engineer at the MITRE Corporation, presented a keynote titled, “Software Supply Chain Integrity Transparency & Trustworthiness and Related Community Efforts.” Check out the presentation materials here or watch the video:

Trust, transparency, and integrity of software supply chains is at the center of many of the global security and safety challenges confronting communities around the world, including government agencies and the industries that support them or provide our critical infrastructure. The pandemic, utility ransomware attacks, the attack on SolarWinds, and the Ever Given have brought supply chain security, resilience, integrity, transparency, and trustworthiness into sharpened focus to a broader audience, and the many inadequacies have surfaced regarding timely access to reliable suppliers, software, and stocks of fuel, personal protective equipment, micro-electronics, medical devices, and food supplies, to name a few.

At the same time, the computerization of everything gave rise to pervasive cyber threats for more and more of the capabilities and infrastructure we and our organizations rely upon to function – including those stemming from vulnerabilities inherent in repurposed software of often dubious provenance and unknown pedigree. Further complicating this landscape is the increasingly globalized nature of the technology in these systems and lack of transparency. Adversaries large and small seek to inject themselves into every conceivable stage of software technology development, supply, and support, for disruptive, monetary and intelligence goals of their own.

This video will discuss the capabilities emerging across industry and government to assess and address the challenges to providing trustworthy software supplies with assurance of integrity and transparency to their composition, source, and veracity – the building blocks of software supply chains we can gain justifiable confidence in at scale and speed.

ELISA Spring 2022 Workshop Recap

By Blog, Workshop

Written by Paul Albertella, ELISA Project TSC member, Chair for Open Source Engineering Process Working Group and Consultant at Codethink

The ELISA Project hosted its annual Spring Workshop on April 5-7. It’s a combination of interesting talks and  productive working sessions on Enabling Linux in Safety Applications. I’ve attended a lot of these over the past three years, but for this one there was a perceptible shift towards  applying techniques and building solutions. If you couldn’t attend, here’s a quick recap of the workshop.

Day 1 opened with an interesting session from Red Hat’s Daniel Bristot and Gabriele Paoloni titled “Safety Monitors inside the Kernel” about a Realtime Verification Monitor concept, which they have been implementing for inclusion in the Linux kernel. This involves using ‘deterministic automata’ (definition here) modules within the kernel that are generated from directed graph models (defined using Graphviz/dot), which are then driven by events within the kernel using ‘instrumentation’ akin to systrace. The goal is to verify the expected behaviour of specific safety-related functionality within the kernel at runtime, and provide a way to trigger a ‘safe state’ mechanism if a problem is detected.

This was followed by a discussion about whether we should add a new ELISA working group with a focus on industrial and/or IoT safety use cases, led by Philipp Ahmann with Bosch GmbH. This discussion aimed to settle opinions about whether ELISA is a proper place to start such a working group, or if there are better communities to reach out to. Watch the video here:

Gabriele Paoloni then gave a talk about PAS 8296, which is an ISO initiative to provide more detailed guidance on applying the 26262 standard to pre-existing software.

The day ended with a keynote presentation by Bob Martin from the MITRE Corporation, which discussed the capabilities emerging across industry and government to assess and address the challenges to providing trustworthy software supplies with assurance of integrity and transparency to their composition, source, and veracity – the building blocks of software supply chains we can gain justifiable confidence in at scale and speed.

On Day 2, Red Hat’s Christoffer Hall-Frederiksen and Gabriele Paoloni were back again, talking about the work that they have done to document how Linux manages address space integrity. This was very informative, providing an accessible overview of how Linux manages processes, threads and memory.

After that, Alessandro Biasci, Raffaele Giannessi and Fabrizio Tronici from Huawei talked about their use of STPA to analyse dynamic memory functionality for Linux, and how some of the risks they identified might be addressed using memory tagging.

I then did a talk on ‘Refining the RAFIA Approach, ​​which addresses the challenges of creating safety argumentation and supporting evidence for systems involving open source software. This talk provided an update on how this approach is being applied and refined, both as part of ELISA workgroup activities and in Codethink’s projects.

The last session of the day focused on the Kernel Configuration database and was presented by Elana Copperman with Mobileye and Wenhui Zhang from Bytedance. This was an attempt to gather together information available on various kernel configuration items that may be relevant when addressing particular risks, together with some notes on best practice when using these. 

This was originally structured using Common Weakness Enumerations (CWEs), and there are plans to include security-related configs as well. One topic of discussion was extending it to include information about the performance impact of the configs, and building automated setups to measure this for reference ‘instances’. At present the ‘database’ itself is just a big Google spreadsheet, but there’s potential for this to become a useful resource. I have been prototyping a solution to migrate the content to a GitHub repository and render it as web pages, which may help.

Day 3 was dominated by two more working sessions. The first, on Mixed Criticality Processing, was a productive discussion which I co-chaired with Chris Temple from Arm. There was some good engagement from existing ELISA participants and new ones, and we ended with a clearer understanding of the challenges faced when safety functions co-exist on a system with non-safety functions, and with other safety functions. There was a broad consensus about how ELISA might provide useful guidance for how to tackle some of these, by describing design patterns for systems that include Linux, rather than focussing on what Linux needs in order to be ‘safe’.

The second session, which I also co-chaired with Philipp, focussed on a possible example of such a pattern, which has been developed for the Telltale use case by the Automotive Working Group using STPA. We talked through the safety concept and control structure, and how we might build on this and implement a reference version based on an existing AGL demo, perhaps using a readily-available hardware platform such as Raspberry Pi.

The last session of the conference is always a working session for next steps and goals that is led by the Linux Foundation’s Shuah Khan, Chair of the ELISA Technical Steering Committee. Shuah and the TSC are currently putting together insights from that discussion, so stay tuned to learn more about the focuses for next quarter. 

If any of these pique your interest, you can go to the new ELISA Project Youtube Channel to see some of these videos or click on the schedule to check out the PPT presentations.