Punch list §25 item 0.4 complete. Adds aarch64_current_el() in arch.c: reads CurrentEL[3:2] on first call, caches the result (CurrentEL cannot change post-ExitBootServices, so every consumer gets the same answer without repeating the MRS). Called from arch_interrupts_init() in interrupts.c -- the earliest point with both a working console (up since M1) and a genuine first consumer (vector installation is the first EL-dependent operation) -- and the detected level is printed to the boot log there. Declared via extern-in-place in interrupts.c rather than added to the shared arch.h: "exception level" has no amd64/riscv64 equivalent, matching the convention already used for riscv64_timer_rearm() in item 0.3. Verified on real QEMU output: "AArch64: running at EL1", correctly positioned immediately before "IDT installed." in the serial log. Boots clean, dict_hash 0x3d4e1daf289da94f unchanged from the item 0.1-0.3 baseline. Scope: this item establishes the detection and exposes it; it does not yet change VBAR/ELR/SPSR or timer-register selection to use it. arch_interrupts_init() still writes VBAR_EL1 unconditionally, and now says so explicitly in its own doc comment -- if aarch64_current_el() ever reports 2 on real hardware, exceptions taken at EL2 vector through VBAR_EL2, which nothing programs yet. That gap is items 0.5 (vectors/saved-state) and 0.7 (CNTP vs CNTHP) to close, per FABRIC.md's GAP-B3 finding. The boot-log EL2 case prints a note pointing at both. Only aarch64-scoped files touched (arch.c, interrupts.c) -- no shared loader or header changed, so amd64 and riscv64 are provably unaffected; not rebuilt for this item. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
experiments/
Design of Experiments (DoE) campaign data and analysis for the LithosAnanke kernel.
bare_metal/— the bare-metal DoE experiment: blind full-factorial 2⁴ runs measuring the L8 Jacquard mode selector's effect on the Steady-State Machine across amd64/aarch64/riscv64. Seeexperiments/bare_metal/README.mdfor the full directory layout (runs/,latest/,analysis/{charts,tables,report}).
Hosted-VM DoE campaigns (factorial/heartbeat/ablation studies) live under
docs/working/experiments/ instead — this top-level directory is
specifically the kernel/bare-metal side.