00mjk / moonos

MoonOS (just a kernel atm) is a micro kernel designed for the x86 architecure supporting 64 bit processors only

Moon OS

Moon OS is a modular micro-kernel targeting the x86_64 architecture, aiming to be POSIX-like in the future.

Screenshots:

Bootsplash:
Verbose boot:
Kernel panic:

Features

• 4 level paging (5 level paging is a meme for a hobbyOS)
• Stacktrace/symbol backtrace
• ubsan
• Basic image rendering (Raw pixel data header file generated by https://github.com/V01D-NULL/img2c)
• Set verbose or quiet boot in the bootloader config file (limine.cfg).
• Elf loader
• zoned bitmap and slab allocators.
• System calls via the syscall instruction (The regular int 0x80 is not supported)
• Physical kernel heap (small slabs (i.e. max of 512 bytes per cache))

Future features:

• IPC
• Threads
• kasan
• APIC
• ACPI
• SMBIOS
• Kernel heap
• Multitasking
• Many hardware drivers including but not limited to:
  • Network cards
  • Storage drivers
  • GPU's
  • And much more
• A libc for the userland

This is currently being working on:

• Scheduler
• Porting mlibc

Directory walkthrough:

• libs/ -- Here you will find kernel libs in the form of archives.
• kernel/ -- Kernel source code, this is most likely all you really care about
• debug-util/ -- Files needed for debugging Moon.
• boot/ -- Everything Moon needs in order to boot

Installation

Building: (assuming you are using a debian based distro)

• Install needed tools:
  • sudo apt update
  • sudo apt install gcc nasm qemu-system-x86 libfuse-dev
• Build kernel
  • make all -- Build the kernel to an ISO file
  • make run -- Run the kernel in qemu and build it if necessary
  • make kvm -- Run the kernel in qemu with kvm and build it if necessary
  • Command line options for kvm and run:
    • modern=yes -- Emulate modern features

My journey: (Inspiration for newcomers)

I have always wanted to make an OS, so one day I decided to build one. Turns out it is a lot of work and back then it totally overwhelmed me to the point where I took long breaks (for months) because information was so scarce, and what little information there is is outdated.

I have written about 4 "kernels" during my OS development learning experience, and each time I started over because I was far too overwhelmed- none have gotten past a GDT :/ (heck, some where just bootloaders that called a kernel entry and looped)

If you are a beginner looking to understand what this code is doing and how you can write your own kernel with up-to-date information, please do join the OSDEV discord server (linked in the osdev wiki at the bottom) and don't give up when it gets hard at first.

I have started developing kernels about 8 months ago at the time of writing (with multiple month-long of breaks in between), and I still have many things to learn, however my try harder mindset proved useful in helping me get through the struggles and write a kernel for which I did not have to steal or copy code from tutorials or other projects out of a lack of knowledge.

I hope this inspired you to use this mindset when things seem too difficult to manage.

Best of luck ~ V01D (Tim).

Special thanks

• Thanks go out to websites like lowlevel.eu or the osdev wiki but also some cool and really helpful os developers on github and discord.

Finishing touch (resources I use)

• https://www.cs.cmu.edu/~ralf/files.html
• https://ethv.net/workshops/osdev/notes/notes-3.html
• https://osdev.wiki (barebones but up-to-date osdev wiki)
• https://wiki.osdev.org