Files
LithosAnanake/include/starkernel
Robert Allan JamesandClaude Sonnet 5 af267a52a6 Artemis Milestone 2h: hot-detach -- 2h complete
blk_subsys_detach_device() (block_subsystem.c) walks the device chain,
refuses removal of anything but the current tail (a mid-chain removal
would corrupt every later slot's start_lbn -- this architecture's own doc
already argues USB stays last specifically to avoid that), unlinks,
shrinks total_user_lbn, closes and frees the slot. Discards rather than
flushes dirty state -- the device is physically gone by the time this
runs (PORTSC disconnect only). Trigger wiring mirrors the attach path:
bot_msc_attached (set only once attach actually succeeds) gates a new
bot_msc_detach_pending flag set at PORTSC disconnect (not Disable Slot
completion, which is conditionally skipped and would miss concurrent
connect/disconnect pairs), consumed in sk_repl_idle().

Advisor flagged the real hazard ahead of time: block_words.c's VM block
window (blk_vm_lbn[]/blk_vm_cbuf[]) can go stale across a detach then a
same-LBN re-attach, and suggested a pointer-identity re-check in
blk_vm_load() as a minimal fix. That fix was implemented, then directly
falsified by its own designed-for-this test: attach a blank device, read
a block (populating the cache), detach, re-attach a device with distinct
content at the identical LBN, read again -- served stale content from
the first device. Root cause, confirmed live: glibc's allocator hands
free(slot) straight back to the very next same-size calloc(), so the
"fresh" and stale pointers were bitwise identical despite being two
different devices. Fixed properly with a monotonic blk_subsys_epoch()
counter (bumped on every attach/detach) checked by a new
blk_vm_check_epoch() helper at the one choke point (blk_vm_find(), plus
blk_vm_flush_all() which reads the same arrays directly) that covers
every path touching the window cache -- unfooled by address reuse.

Verified live with a new disk/usb-thumbdrive-test2.img fixture (distinct
content from the existing blank test image): attach A, read (cache hit
populated), detach, re-attach B at the same LBN, read again -- correctly
ran a fresh device read and returned B's real content, not A's stale
cached zeros. The failing pointer-comparison attempt's own capture log
kept as evidence, not deleted. All three architectures re-verified clean.
FABRIC-2.md Section X 2h marked complete -- enumeration through
hot-detach all live and verified; only WRITE(10) (2g's own still-open
item) remains unimplemented in the driver, not blocking anything here.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CXjAPTEKrgY2Mrk25KoLDn
2026-08-25 14:10:05 -04:00
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include/starkernel/

Headers for LithosAnanke, the bare-metal UEFI kernel (src/starkernel/). Built only via Makefile.starkernel; gated by __STARKERNEL__ when shared with hosted code.

  • uefi.h — UEFI protocol/type definitions consumed by the loader.
  • elf64.h, elf_loader.h — ELF64 parsing and kernel-image loading.
  • boot_info_offsets.h — struct-offset constants shared between the assembly bootstrap and the C boot path.
  • arch.h, apic.h, timer.h — architecture init, APIC interrupt controller, timer (TSC/HPET/APIC, 100 Hz heartbeat).
  • console.h, framebuffer.h, vt100.h — UART 16550 console, framebuffer driver, and VT100 terminal emulation over the framebuffer.
  • pmm.h, vmm.h, kmalloc.h — physical memory manager (bitmap allocator), 4-level x86_64 paging, kernel heap allocator.
  • pci.h, virtio_blk.h — PCI enumeration and the VirtIO block device driver (disk backend for the kernel block subsystem).
  • capsule.h, capsule_birth.h, capsule_loader.h, capsule_run.h, capsule_vm_physics.h, capsule_generated.h — capsule system types, birth protocol, physics-runtime capsule bindings, and the build-time- generated capsule directory (see tools/mkcapsule.c).
  • kernel_args.h, cmdline.h — boot-time kernel argument parsing (starforth.cfg / command line).
  • repl.h — kernel REPL.
  • log.h, doe_log.h — kernel logging and DoE metrics logging.
  • q48_16.h — kernel-build copy of Q48.16 fixed-point arithmetic.
  • xxhash64.h — content-addressing hash used for capsule IDs.
  • hal_memory.h — hardware-abstraction-layer memory interface.

Subdirectories:

  • hal/ — top-level hardware-abstraction-layer interface.
  • vm/ — kernel VM subsystem headers (capsule arena, parity logging, bootstrap wiring).
  • freestanding/ — minimal libc-shim headers (assert.h, ctype.h, errno.h, inttypes.h, math.h, sched.h, signal.h, stdio.h, stdlib.h, string.h, time.h, sys/time.h, sys/types.h) for building shared VM code in the freestanding kernel environment, where no real libc is available.