danielandClaude Fable 5
5db2bd4c7c
MontaukOS binaries could not use thread-local storage: the ELF loader ignored PT_TLS and no FS base was ever programmed, so any %fs access (initial-exec/local-exec TLS, e.g. libbfd's _Thread_local error state) page faulted at address 0. This is the kernel prerequisite for cc1plus/libstdc++ in the GCC port. ELF loader: parse PT_TLS and build the main thread's TLS block above the loaded image (x86-64 variant II ABI: block below the thread pointer, TP = base + align_up(memsz, align), .tdata copied from the template, .tbss zeroed, ABI self-pointer stored at [TP]). The template description is kept on the process for thread spawns. Scheduler: fsBase per thread, loaded into IA32_FS_BASE at every dispatch site through a per-CPU cache - TLS-free processes cost one MSR write per CPU ever, and userspace cannot desync the cache since CR4.FSGSBASE stays off. SYS_THREAD_SPAWN gives each new thread its own TLS block copied from the template (allocated from the process heap; reclaimed at process teardown). Ships tls-test.elf in the SDK (built by the devkit target): checks .tdata values, .tbss zeroing, and the %fs:0 self-pointer, exiting nonzero on failure. Boot-smoke verified; existing TLS-free programs are unaffected. Co-Authored-By: Claude Fable 5 <[email protected]>
doomgeneric
@ fc60163949
The Montauk Operating System
MontaukOS is an operating system written in modern C++. It runs on bare metal and supports various applications, including DOOM, a Wikipedia client, and standard desktop utilities.
Features
- Modern preemptive multitasking kernel
- Multi-user userspace with desktop environment and command line
- PCI-e support and drivers for Intel GPU and e100e Ethernet for graphics and networking on real hardware
- ACPI support with AML interpreter, including S3 sleep and ACPI shutdown
- Support for USB including input devices (keyboard/mouse), along with PS/2 input support
- Support for Intel High Definition (HDA) audio devices
- Userspace and kernel audio support
- Support for (some) Intel Bluetooth devices, userspace Bluetooth management app
- Support for the GPT partition table
- VFS using numbered drive identifiers with support for ext2 and FAT32 filesystems
- Support for AHCI and NVMe SSD drives
- Support for UEFI Runtime Services, including power management calls (shutdown/reboot)
- Customizable desktop environment with 12+ graphical apps, including a terminal emulator, file manager, Wikipedia client, weather app, DOOM, and more
- Modern icon pack (Flat Remix) used in desktop environment
- Support for TrueType font, JPEG image, and SVG icon rendering
- Networking including TCP/IP stack, UDP, DNS, DHCP and TLS via BearSSL
- Command-line IRC client
- Live viewable kernel log from GUI
- Mandelbrot set renderer
- PDF viewer app with full support for text (inc. baked-in TrueType fonts) and some graphics
- Userspace Music app with support for MP3 and WAV files
- 2D game engine and demo game with fantasy tileset
Goal
The goal of the MontaukOS project is to create a modern and unique operating system that runs on both emulators and on real hardware. The kernel and included userspace applications are written in modern C++.
History and methodology
Development started in early 2025, as a hand-written toy kernel. The first published Git commit was on Feb 27, 2025. In early 2026, Claude Opus 4.6 began being used to accelerate development of the kernel and userspace.