Simple, kernel-only, 64bit OS, early stage. https://git.2137697.xyz/rs-dos/atom?h=qemu 2026-08-02T13:21:34Z 2026-08-02T13:21:34Z salmonik salmonik@tuta.io 2026-08-02T13:21:34Z urn:sha1:c7d92071e1dd11c45999457b16554b4abaa73b28 The fault handler now writes crash.log to the volume labeled CRASHLOG (label-selected via fat::crash_vol), falling back to slot 0. On real hardware the boot USB may be unwritable, so a second stick labeled CRASHLOG survives the write; the shell auto-prints the previous crash report from it at next boot (read_crash_log resolves /disk/<uid>/crash.log through the FAT path, since Disk nodes hold no cached children). - fat.rs: volume_label() + crash_vol() (no allocation) - fs.rs: write_crash_log targets crash_vol(); read_crash_log prefers the CRASHLOG disk node; drop now-unused first_disk() - mkdisk.sh: --label option - test-fault.sh: boots with a dedicated CRASHLOG stick (mkfs -F 32 -n CRASHLOG), verifies crash.log lands there and NOT on the ESP 2026-08-01T15:38:57Z salmonik salmonik@tuta.io 2026-08-01T15:38:57Z urn:sha1:8f05ea44f69cb796e7b1f581ba1b8045c98d615b - sched: 16-slot static table, shell=task 0, idle=task 1, spawn with guard page + 8 KiB stack, RR on the 100 Hz tick, int 0x60 yield, sleep_ms, lazy reap, jobs/bg/sleep/kill shell commands - gdt: own GDT mirroring UEFI selectors + TSS with IST1/IST2 (guard-page overflows die gracefully instead of triple-faulting) - interrupts: isr_dispatch returns next frame in rax; IntFrame grows rsp/ss fields — QEMU's 64-bit iretq always pops all five slots from a 176-byte frame, so synthetic task frames must carry rsp=top+ss (a 160-byte frame made the first iretq pop rsp/ss from the unmapped page beyond the frame) - panic handler: task panics abort the task, shell keeps running - main: sched::init moved after page allocator + adopted tables (the idle's stack+guard need both; it was silently not spawning)