Same Firmware, Different Behavior: Understanding Configuration Effects in EDK2

The article discusses how firmware configuration changes can impact execution behavior in EDK2 firmware. It highlights that configuration alterations can reshape execution without affecting boot time and explores the nonlinear performance effects of certain configurations. The study uses an instrumented EDK2 build to analyze multiple boot runs across configurations, revealing subtle changes in execution sequences. Different modes of firmware behavior are identified: structural changes that redistribute work without affecting runtime, and regime shifts where configuration changes dominate runtime behavior. The article emphasizes the importance of evaluating configurations in combination and understanding how they affect system behavior.