Robert Allan JamesandClaude Sonnet 5
b24a5a6e25
Root cause of the aarch64 BYE cold-restart exception (present since at least 2026-08-08, ESR_EL1=0x02000000/EC=0 "Unknown reason"), found via live gdb single-stepping through the actual crash: arch_cold_reset() issued PSCI SYSTEM_RESET via `smc #0`, but QEMU's aarch64 virt machine booted with AAVMF (UEFI firmware, no genuine EL3/TrustZone secure monitor) serves PSCI via HVC, not SMC -- nothing exists to answer an SMC call, so it trapped as an illegal instruction straight into the kernel's own exception handler. Not memory corruption, not a race -- a wrong conduit for this boot configuration. Fix: smc #0 -> hvc #0. Function ID and calling convention unchanged. Getting to this required first discovering that starkernel_kernel.elf is not the binary that actually runs -- MONOLITHIC_BUILD links kernel_main() directly into starkernel_loader.efi, a completely separate, differently-linked build artifact. Every earlier gdb breakpoint attempt this session failed because it used addresses from the wrong file. Real addresses (UEFI-chosen ImageBase + linker-map RVA) let gdb catch the crash live for the first time. Verified: full aarch64 acceptance pass, 30/30 stress-campaign reps PASS (unaffected -- this bug only manifested on BYE), and BYE now exits cleanly with no exception for the first time in this investigation. Full writeup in FABRIC-2.md Section I. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
src/starkernel/
LithosAnanke — the bare-metal UEFI kernel that boots StarForth directly on
hardware (amd64/aarch64/riscv64). Built only via Makefile.starkernel; the
only valid acceptance test is the three-arch QEMU boot (see
.claude/CLAUDE.md), never make test.
kernel_main.c— kernel entry point, driving the boot milestones (console init, PMM, VMM, interrupts, timers, kmalloc heap, VM bootstrap).repl.c— kernel REPL.doe_log.c— kernel-side DoE (Design of Experiments) metrics logging.
Subdirectories:
arch/{amd64,aarch64,riscv64}/— per-architecture support (APIC/GIC/ PLIC interrupt controller, timers, boot/ISR assembly).boot/— UEFI loader, ELF loading, kernel command-line parsing.capsule/— capsule birth/run/load/validate pipeline.hal/— hardware-abstraction-layer implementation (console, framebuffer, VT100, memory, host services).hash/— XXHash64 content-addressing implementation.math/— kernel-build Q48.16 fixed-point arithmetic.memory/— physical/virtual memory managers and the kernel heap.pci/— PCI bus enumeration.virtio/— VirtIO block device driver.vm/— kernel VM subsystem (bootstrap, core interpreter, parity logging, capsule arena).
See include/starkernel/README.md for the corresponding headers.