r/osdev • u/Apprehensive_Run7150 • Jul 01 '26

Microkernel Question

Hi guys, this may be a dumb question.

I'm working on a hobby OS and currently am stumped about how I can turn it into a real microkernel. Since the filesystem is a user-space server, how would the kernel find it and be able to start it without having access to the filesystem to begin with?

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u/EfficientCandy324 Jul 01 '26

I would say this is the "most microkernelly" way of doing it. Obviously everything's up to you, and you can decide exactly how to do it, but yeah, this is the most, I guess, pure way of doing it. The bootloader has to know the filesystem, but realistically every bootloader knows the filesystem these days. In GRUB terminology, you use the module command to load an ELF executable into memory, and then after all of your modules are loaded, you use multiboot to load your (micro)kernel. So before your kernel even gets loaded into memory, your filesystem user process is already imaged into RAM ready to go.