Files
LithosAnanake/logs
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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2026-08-02 05:11:24 -04:00
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logs/

QEMU acceptance-run history and Tripod smoke-test results.

  • <timestamp>/{amd64,aarch64,riscv64}/ — 255 timestamped three-arch QEMU acceptance run directories, one per invocation of the kernel QEMU acceptance workflow.
  • qemu-screenshot-*.png, qemu-screenshot-*.log, qemu-{amd64,aarch64,riscv64}-*.log, fbtest-console-*.png — loose timestamped QEMU serial captures and framebuffer screenshots from individual manual runs (not part of the timestamped-directory convention above).
  • hermes-tripod-smoke-results.md, hermes-channel-smoke-results.md — captured output from tools/hermes_tripod_smoke.sh and tools/hermes_channel_smoke.sh.
  • hermes-tripod-integration-design.md — design notes for the Tripod integration test.

Note: QEMU_BASELINE.log at the repo root (not in this directory) is the primary kernel regression baseline referenced by .claude/CLAUDE.md; the logs here are supplementary historical captures. See also logs2/ (a separate, flatter QEMU log archive) and experiments/bare_metal/runs/ (DoE-specific run output).