On riscv64 a system=v3 boot never reached its prompt: Artemis's writes
"timed out" and Zuse was never confirmed (logs/20261026-134850). vblk_io()
bounded its wait by ~1M polling iterations, which on riscv64 under TCG is
about one heartbeat tick of real time -- shorter than a write that allocates
space in a sparse host image. Instrumented, the request was seen completing
just after the give-up ("used idx=409 last=408"), and every later request
then took its predecessor's completion for its own and returned before its
own I/O was done (a stale used index at each later request), reusing the
descriptor chain while the device still owned it: silent read and write
corruption from that point on. FABRIC-3.md's 2026-09-09 "request that never
gets a used-ring completion" is this same early give-up.
Now: the wait is for this request's own completion (the used index
reaching the avail index it was given), bounded by 5 s of real time on the
CPU's counter (timer_now_ns(), which needs no interrupts); a request that
truly never completes takes the disk out of service instead of letting a
later request reuse the chain.
Red (riscv64 system=v3, with temporary instrumentation): 151003, 151100 --
a timeout then dozens of stale completions each. Green: 151238, 151332 --
none; Zuse confirmed; the keyboard line answered. system=v3 with the fix:
riscv64 151438, amd64 151528, aarch64 151610, no timeouts. Accepted (v4):
151722, 151916, 152247, POST 538/538, dict_hash 0xfec8c47cfc6f437f;
test-32, 39 modules, 0 failures.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Source tree reorganization:
- Move StarForth v3 engine to v3/ (src/, include/, Makefile)
- Move kernel to kernel/ (src/, include/, linker/, Makefile)
- Create v4/ skeleton for F18-ISA golden model (DECOMPOSITION.md, JUSTIFICATION.md)
- Move FABRIC-0..4.md to docs/fabric/
- Move ONTOLOGY.md and ROADMAP.md to docs/
Board infrastructure:
- Add boards/ser5/, boards/raspi/, boards/milkv/, boards/zynq7020/
- Each board has board.mk (ISA, CPU flags, boot recipe) and README.md
- Root Makefile becomes thin dispatcher: boot_image, all, clean, docs take TARGET
- make boot_image TARGET=SER5|RASPI|MILKV builds one GPT/MBR image per board
- ZYNQ7020 target exists but stops with clear error (ARMv7 port not built yet)
- scripts/mkdiskimage.sh builds disk images for all boards
Docs pipeline:
- docs/book/ with LaTeX master (main.tex) and Makefile
- pandoc converts Markdown to LaTeX at build time
- Two Lua filters: table-widths.lua (wide tables wrap), code-breaks.lua (inline code breaks)
- make docs builds single PDF (754 pages, 0 missing characters)
- make docs TARGET=<board> adds board appendix
- build/docs/<book|board>/meta.tex stamps git commit into PDF
Bug fixes:
- 42 include paths that only worked by accident now use correct relative paths
- clang-18 hardcode replaced with configurable CC variable (fixed aarch64 build)
- Pi 5: kernel_2712.img linked at 0x80000, .bss zeroed, memory reserved
- Doxyfile, .clang-tidy, README.md, Kconfig paths updated
Verified:
- Hosted v3 build passes 1012 tests, 0 failures
- SER5 image boots in QEMU (OVMF), POST passes, K exact (65536 = Q48_ONE)
- Milk-V image boots in QEMU (OpenSBI + U-Boot + bootefi), POST passes
- make clean TARGET=<board> removes only that board and its ISA objects
- make all builds all boards, hosted v3, and docs in one run
Co-authored-by: Junie <junie@jetbrains.com>
