Simple, kernel-only, 64bit OS, early stage. https://git.2137697.xyz/rs-dos/atom?h=qemu 2026-08-03T00:23:35Z 2026-08-03T00:23:35Z salmonik salmonik@tuta.io 2026-08-03T00:23:35Z urn:sha1:9fde94d068f87b34e0bc6bfa48388d89bb54f1e4 Real hardware has no serial console, so a kernel crash only leaves a frozen screen. Every dump_lines() report now also renders the crash text as a scannable QR below the white-on-red band (photograph the screen instead of relaying text). - rsnix/src/qr.rs: from-scratch no_std/no_alloc byte-mode QR encoder (EC-L, v1..v40, .bss statics only — safe on the fault path): RS over GF(256), codeword interleave, zigzag placement, 8 masks with N1-N4 penalty auto-selection, format/version info. - gop.rs: dump_qr() joins dump lines into a static buffer, truncates with '...' at the v40-L capacity, encodes, and renders centered black-on-white with a 4-module quiet zone. - tools/qrcheck: host harness (embedds qr.rs) + qrcheck.py cross-check against segno's placement primitives. Verified bit-exact: 12 versions x 8 masks forced, plus auto-mask choice matches segno's penalty evaluation. Caught 3 encoder bugs (multi-block interleave offsets, transposed version info, mask eval ordering). - QEMU e2e: page-fault dump screendump decodes via zbarimg, content matches the serial log line-for-line. - test-msg.sh and test-fault.sh both PASS; debug+release 0 warnings.