2/24/2026 Michael O'Boyle
CS Ph.D. student Wentao Zhang and his collaborators at Boeing were awarded a best paper at the 2025 Digital Avionics Systems Conference for developing safety-testing infrastructure for the Linux kernel, advancing the goal of certification for commercial aviation. Zhang is co-advised by computer science professors Darko Marinov and Tianyin Xu.
Written by Michael O'Boyle
In work awarded a best paper at the 2025 Digital Avionics Systems Conference, Siebel School of Computing and Data Science graduate student Wentao Zhang and his collaborators at Boeing developed safety-testing infrastructure for the Linux kernel, advancing the goal of certification for commercial aviation.
Linux, a free and open-source operating system kernel, is used in many computer systems from large-scale data centers to mobile Android devices. Its popularity and active development community make Linux a strong candidate for use in the aviation industry. However, it is necessary to rigorously evaluate and certify the safety of Linux based on regulatory requirements.
Researchers in The Grainger College of Engineering at the University of Illinois Urbana-Champaign and The Boeing Company have taken the first steps to evaluating and certifying Linux for aviation, developing a specialized testing infrastructure.
The status of their work was presented at the 2025 Digital Avionics Systems Conference, where the paper “An Open-Source Structural Coverage Tool for DO-178C Compliance” was awarded first place in “The Best of Conference” Awards.
“Our goal is to ‘make Linux fly,’ and the first step is to ensure that the kernel meets safety standards,” said Ph.D. student and lead author Wentao Zhang. “We are working on measuring the test adequacy of the Linux kernel code to understand the gaps. Our work with Boeing researchers has resulted in an infrastructure that can help perform mandated safety tests on Linux.”
Zhang is co-advised by computer science professors Darko Marinov and Tianyin Xu.
“Wentao’s work is a great example that shows the real-world research impacts of our students.” Xu said, “Software reliability is no longer only in academic papers but in fact influences the software to be deployed on airplanes, which everyone’s life relies on at some point of time.”
The researchers addressed an aspect of software certification known as “code coverage”, which indicates how adequately the software has been tested. Most aviation regulatory bodies in the world, including the Federal Aviation Administration, use the RTCA DO-178C standards for code coverage with an emphasis on a specific code coverage criterion known as MC/DC (Modified Condition/Decision Coverage). The goal is to demonstrate Software Level A, the highest available certification, for Linux.
“Certification is mostly done for user space applications that run on an operating system,” Xu said. “Certifying the safety of the operating system kernel itself requires additional support. For example, coverage measurement tools usually depend on OS services such as writing coverage reports into a file. However, in the kernel space, there is no file-writing abstraction, so we used debugs to persist in-memory data to the disk.”
Zhang worked with the team led by Boeing Technical Fellow Steve VanderLeest, an Illinois Grainger Engineering alum, to create specialized tool chains that measure Linux’s code coverage. In fact, a significant part of the research was verifying the tools themselves.
“Our contributions in the DASC paper are twofold: the testing infrastructure and ensuring the correctness of the infrastructure,” Zhang said. “When we went into the open-source tool kits for testing, we found that many of them are ambiguous, misleading or even wrong. We hope that our results will lead to more accurate numbers and reports that are easier to understand.”
Zhang, Marinov and Xu recently published their results on testing the code coverage tools at the 2025 International Conference on Automated Software Engineering (ASE).
Even with the new specialized testing infrastructure, the task of fully certifying Linux remains daunting.
“Our work shows that the code coverage of existing MC/DC Linux tests is very low, only 7%,” Marinov said. “How to significantly improve the test coverage of the Linux kernel is our next big problem and would need community support.”
The team has given a series of technical talks that outlines the problem and their progress at major industry venues such as the ELISA seminar and the Linux Plumber Conference.
Financial support was provided by The Boeing Company.
Illinois Grainger Engineering affiliations
Darko Marinov is a professor of computer science in the Siebel School of Computing and Data Science.
Tianyin Xu is an associate professor of computer science in the Siebel School of Computing and Data Science. He is also affiliated with the Department of Electrical and Computer Engineering.