- Ruling (Captain Bob): per-slot locks, not "own path needs no lock" --
a lock only on the cross-slot side can't exclude an unlocked owner
(Hermes release evicting a sender's cell while the sender admits).
FABRIC-3.10.0 §3.6 amended.
- StadiumVMQuota.lock covers the slot's lists, reservoir, consumed, word
row and its cells. Word dispatch holds only its own slot lock for the
whole dispatch (*_in_slot forms); peek-then-pull is one step.
- g_lock_stadium: grant slot allocation (new slot published with release
in_use) and the shared block table (ruled: the one shared-lock Stadium
path). Taken before a slot lock.
- Bitmap bytes set/cleared atomically (8 cells, possibly 8 slots).
- Cross-slot writers moved under the owner's lock: Hermes decay
(stadium_cell_decay), Hermes release ledger (stadium_evict_credit),
session pin (stadium_cell_set_pin). stadium_conserved() one hold.
- Word and block cell lookups check the cell is still this slot's.
- Probe (removed), identical on all three ISAs: 10,746,599 of 10,746,616
word dispatches took exactly one lock (own slot), the 17 others all row
growths; every live VM conserved; Hermes audit failures 0.
- Findings reported: births/USE run a VM's words while another VM is the
core's current VM (MC-3 claim must cover it); quota slots never
released; owner admission can evict a live message cell (latent, 0).
- Standard sequence on amd64/aarch64/riscv64: dict_hash set and G
byte-identical, MINT/WIREBIND/USE ok, conservation true, 0 idle growth.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- block_subsystem.c (vendored): every public function's body becomes a
static *_locked function; bodies call each other only through the
_locked forms, breaking the internal cycles (relocate, meta relocate,
migration scan, firsttouch, the meta accessors). Thin public wrappers
take g_lock_block under __STARKERNEL__; hosted build has no lock and
still builds clean.
- Lock order: hermes, switch, registry, doe, log, block, console, heap,
vmm, pmm (Stadium, MC-0d, above block).
- Documented, not coverable by this lock: blk_get_buffer() pointers are
used after release -- block-buffer ownership across cores is open for
MC-3.
- Probe (removed): block lock balances on all three ISAs (2,057-2,379
acquisitions), 0 recursions, 0 held at switch; vblk_io timeouts
(0/0/4 probe, 0/0/2 acceptance) within the pre-lock riscv64 baseline
of 0-6.
- Standard sequence on amd64/aarch64/riscv64: hashes and G byte-identical
to MC-0b, MINT/WIREBIND/USE ok, conservation true, 0 idle growth.
- FABRIC-3.10.8 §3.2 wording fix; lock order noted as checked by
inspection only.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- New spinlock primitive (spinlock.h/.c): CAS on an owner word (core+1),
interrupts masked while any lock is held (state kept in the per-core
block, so release order doesn't matter). Recursion, release-not-held,
held-at-switch and destroyed-while-held are counted and logged, never
silent. Locks are no-ops until the boot core's block is installed
(riscv64's monolithic early boot prints before sk_percpu_boot_init()).
- Kernel locks in a documented order: hermes, switch, registry, doe, log,
console, heap, vmm, pmm. sf_mutex (dict_lock/tuning_lock) uses the same
lock word.
- Hermes: public functions over *_locked internals; never held across the
drain's vm_interpret_kind(); switch notifications after dropping the
lock; event payload moved off static storage. Switch table and registry
never call out while held (slot/entry copied under the lock).
- No lock crosses a switch: checked at context switch (leave, resume) and
the idle point.
- Probe (removed): every lock balances on all three ISAs; 0 held at
switch over 7.5M-51M checks; 0 recursions, 0 bad releases.
- Standard sequence on amd64/aarch64/riscv64: hashes and G byte-identical
to MC-0a, MINT/WIREBIND/USE ok, conservation true, 0 idle growth.
- Block subsystem split out as MC-0b2 (Captain Bob's ruling).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
