Microkernel Notes

Minimal kernel ; Does only scheduling, memory management and IPC.

Language

Written in Rust, C++, Zig, … ?

C++

• C++17 (20?)
• No exceptions or RTTI

Rust

• Memory safety
• See Redox

Zig

• Nice error handling facilities
• See zen

Features

Linux (not POSIX) server

• provides Linux syscalls for other processes

Linux driver server

• can load and run Linux kernel modules using some sort of shim
• since all the Linux drivers will simply be userspace programs, we can use GPL drivers without having to release the kernel as GPL (?)

Microkernels

• Minix
  • C, NetBSD userspace
• L4
• Redox
  • Rust, userspace C library written in Rust
• Fuchsia (Zircon), Google
  • C++17, based on littlekernel
• GNU Hurd
  • C, based on old Mach kernel, interesting concepts (translators, etc), 30 years in the making still not finished…
• QNX
• HelenOS
• Barrelfish

Books & Papers

• Operating Systems Design and Implementation by Andrew S Tanenbaum , Albert S Woodhull
• The Increasing Irrelevance of IPC performance in Microkernel-based Operating Systems by Brian N. Bershad
• The Persistent Relevance of IPC performance in Microkernel-based Operating Systems by Wilson C. Hsieh, M. Frans Kaashoek, and William E. Weihl
• µ-Kernels Must And Can Be Small by Jochen Liedtke

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• Hardware/Software Co-Design for Efficient Microkernel Execution, Martin Děcký, Fosdem 2019