Robert Allan JamesandClaude Sonnet 5
00e657019e
Replaces STADIUM_MAX_VM_COUNT (Kconfig, hardcoded default 4) with a boot-time computation, mirroring the pattern stadium_boot_init() already used for the cell pool. New Kconfig STADIUM_VM_MEMORY_PERCENT (default 50): max_vm_count = (kmalloc_get_stats().free_bytes after the cell array * STADIUM_VM_MEMORY_PERCENT / 100) / VM_MEMORY_SIZE, floored to 1, no ceiling (population is not knowable in advance - could be 4, could be 4000). stadium_quotas and word_slots (plus stat_promotions/stat_evictions) are now kmalloc'd to the computed count instead of declared with a macro. New accessor stadium_max_vm_count() replaces every STADIUM_MAX_VM_COUNT reference, including capsule_birth.c's birth-refusal gate. Two things found and fixed along the way: - The existing cell-pool budget was sourced from pmm_get_stats(), which reflects physical pages PMM hasn't handed to any subsystem yet - but the actual allocation is kmalloc(), which draws from the separate, fixed-size heap kmalloc_init() (M6) already carved out of PMM before stadium_boot_init() ever runs. Budgeting against PMM's leftover and allocating from the kmalloc heap are two different pools. Both the cell budget and the new VM-count budget now source from kmalloc_get_stats() instead. - stadium_owner[] (which VM's quota owns each cell) was uint8_t, capped at 255 slots by a compile-time assert tied to the old macro. Widened to uint16_t (65535 slots of headroom) with a runtime clamp + log if the computed count ever exceeds that, since there's no ceiling anymore. Three-arch QEMU acceptance: all clean to ok>, computed VM count genuinely differs by actual available RAM (amd64/riscv64: 50 slots at -m 1024, aarch64: 101 slots), Stadium conservation invariant identical across all three (resident_sum=43691 reservoir=21845 sum=65536). logs/20260815-080526/amd64, logs/20260815-080826/aarch64, logs/20260815-080952/riscv64. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
disk/
QEMU disk images used for Artemis (block-storage VM) persistence testing.
Mounted via Makefile.starkernel's ARTDISK variable (default
disk/artemis.img) as a virtio-blk-pci device on all three
architectures' kernel QEMU boots — not scripts/rundisk.sh, which targets
a separate, currently-unused disks/ (plural) directory for the hosted
VM's --disk-img= flag instead.
artemis.img— standard Artemis persistence test disk. Reformatted 2026-08-02: this image had been stuck in a corrupted state (validLithosAnankemagic header, but data not matching whatART-READ-TESTexpects) since before this repo's own git history begins (git logshows it already broken at the initial commit, carried over from the pre-split monorepo). Chasing down the resulting persistentFAIL: persist-readtraced to the data, not the code — the write→reboot→read round trip works correctly on a fresh image (seeartemis-debug-roundtrip.imgbelow). Reformatted by blanking the file and letting a normal boot format+write-test it; verifiedPASS: persist-readon amd64, aarch64, and riscv64 against the same image afterward (cross-arch resume, matching the arch-neutral on-disk format.claude/ARTEMIS.mdspecifies).artemis-debug-roundtrip.img— round-trip regression fixture created during that investigation. Known-good: format → self-test → write-test → reboot → resume →PASS: persist-read, confirmed 3 times in a row. Keep this in a passing state; if a future change breaks it, that's a real regression, not a stale-fixture artifact likeartemis.imgwas.artemis-persist-test.img— persistence round-trip test image (pre-existing; history/state not re-verified during the above investigation).artemis-poison.img— a separate test image (exact scenario not documented elsewhere in the repo as of this writing; name suggests an adversarial/corruption test, not confirmed).artemis-unrecognized-test.img— exercisesART-HALT-UNRECOG(.claude/ARTEMIS.mdacceptance criterion #6). Regenerated 2026-08-02: the previous copy of this file had itself been silently reformatted by a since-fixed bug in the generic block subsystem (src/block_subsystem.c) — it carried a valid low-level'STFR'/v2 header despite being meant to represent foreign disk content, direct forensic evidence of the bug described in.claude/ARTEMIS.md's Build Status item 6. Regenerated as 30MB of a repeatingPOISON-UNRECOGNIZED-DISK-TEST-FIXTURE--NOT-BLANK-NOT-STFR-NOT-ARTEMIS--ASCII pattern — deliberately neither blank, nor the block subsystem's own'STFR'magic, nor Artemis's"ARTEMIS\0"marker. Verified on amd64 and riscv64 post-fix: boot correctly halts (ARTEMIS HALT: unrecognized disk content) and the file's sha256 is now byte-for-byte identical before and after boot. Keep this fixture in this poisoned state — if a future change makes its sha256 change across a boot, that is exactly the regression this fixture exists to catch.
Note on incidental header churn: artemis.img picks up a few changed
header bytes on every ordinary boot even though no user data changes —
blk_subsys_attach_device() always records a fresh mounted_time on a
successfully recognized disk, which gets flushed at shutdown. This is
expected bookkeeping, not a bug; revert it before committing rather than
carrying timestamp noise in git history.
These are regenerable QEMU raw disk images, not source — see
.claude/ARTEMIS.md for the storage model they exercise.