I work on several multi-platform project that use GitHub Actions for continuous integration testing. GitHub Actions basically use Docker images to emulate or virtualize different processors and operating systems.
Lately some of the CI tests have failed under Docker, but work on real hardware, or when using qemu-user directly without using Docker container. It seems some of the machines hosting Docker runners are incompatible with qemu, and cause qemu to abort with error message "Illegal instruction". As the Docker instances on GitHub Actions are non-interactive, there is no chance attaching debugger to the instance and dumping what instruction causes the qemu to abort with signal 4.
