The author describes debugging a persistent random lockup bug while building a bare-metal ARM64 hypervisor for postmarketOS, triggered by enabling CTR_EL0 interception. The post walks through the systematic hypothesis-driven investigation of ARM64 exception handling and special function register access. It highlights the real-world challenges of low-level hypervisor development on ARM architecture.
Background
ARM64 supports virtualization extensions (EL2) that allow building bare-metal hypervisors. postmarketOS is a Linux distribution targeting smartphones, and running a hypervisor on mobile ARM SoCs is an active area of experimentation.
- Source
- Lobsters
- Published
- Sep 4, 2026 at 02:27 PM
- Score
- 5.0 / 10