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* v0.5.9: fix OptiPlex heap crash — EBS retry must not rebuild the free listsalmonik2026-08-041-49/+128
| | | | | | | | | | | | | | | | | | | | | | | Root cause: on real hardware SetMode can invalidate the pre-captured ExitBootServices map key, so EBS fails and the retry refreshed the map via capture_memory_map -> init_heap, which REBUILT the free list from the raw map and wiped the allocation state of every pre-EBS live object (the display shadow and the vt grids). Their spans became free while still live, later allocations carved inside the shadow, and the display writes clobbered them — zeroed back-pointers (family A ptr=0x404443e0 block=0x0) and gray glyph pixels (family B 0xaaaaaa00aaaaaa = 0x00AAAAAA = PALETTE[7] fg-7 text colour, not a firmware scrub). Fix: refresh_and_exit now re-captures the map and returns a fresh EBS key without rebuilding the free list (refresh_map_key); the free list is the authoritative live-allocation state. Verified in QEMU under a forced EBS failure (SIMULATE_EBS_FAILURE test hook): verify ok, probe NOT free, flhead outside the shadow — identical to a clean boot, and the full shell sequence is crash-free. Also: removed the crash-family debug markers from the screen (boot-time heapdbg lines, vt verify marker, shadow marker) — the vt grid self-check stays serial-only. Version 0.5.8 -> 0.5.9.
* v0.5.7: fix vt verify content check — expect BLANK (0x70020), not zerosalmonik2026-08-031-0/+204
The pre-verify 0x70020 'mystery' was a debug artifact, not corruption: BLANK = {ch:32, fg:7, bg:0} = raw 0x70020, and vec![BLANK; n] fills both grids with it at init. The old check compared cells against 0 and its probe loop break-ed on the first non-zero cell, so probes 1-3 stayed at their zero-initialized slots — c=[0x70020,0,0,0] was bogus on every healthy boot. A full-grid dump proves QEMU grids are 100% BLANK at shell entry (nz=3700 blank=3700). Fix: probes compare against blank_raw (0x70020), record all four values (no early break), probe both cells and rendered, and add a full-grid nz/blank summary line. The OptiPlex firmware 0x00AAAAAA scrub remains cleanly distinguishable (scrub != blank). Markers: the shell banner occupies grid rows 0-1 and the prompt row 2 (proven by screendump), and a stale crash.log replays at rows 2+, so the shadow and vt markers moved to the bottom of the screen via the new gop::text_rows()/bottom_row(off) helpers instead of rows 1-2. QEMU verified: verify: ok every boot; test-msg + test-fault PASS; debug and release builds 0 warnings.