Hypervisor in 1k Lines

Posted4 months agoActive4 months ago

lioeters

129 points

15 comments

1000hv.seiya.meTechstory

calmmixed

Debate

40/100

HypervisorVirtualizationOperating Systems

Key topics

Hypervisor

Virtualization

Operating Systems

A 1000-line hypervisor written in Rust has been released, sparking discussion about its simplicity, practicality, and comparison to other similar projects.

Snapshot generated from the HN discussion

Discussion Activity

Light discussion

First comment

Peak period

15-18h

Avg / period

2.1

Comment distribution15 data points

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Based on 15 loaded comments

Key moments

01Story posted
Sep 9, 2025 at 7:13 PM EDT
4 months ago
Step 01
02First comment
Sep 9, 2025 at 9:08 PM EDT
2h after posting
Step 02
03Peak activity
4 comments in 15-18h
Hottest window of the conversation
Step 03
04Latest activity
Sep 11, 2025 at 1:38 PM EDT
4 months ago
Step 04

Generating AI Summary...

Analyzing up to 500 comments to identify key contributors and discussion patterns

Discussion (15 comments)

Showing 15 comments

userbinator

4 months ago

1 reply

See also https://ionescu007.github.io/SimpleVisor/ in around 500 lines of C.

notorandit

4 months ago

1 reply

That's not risc-v, though.

notorandit

4 months ago

Why demoting? It Is x86-64 only!

chubot

4 months ago

2 replies

Hm I would like to see this in C rather than Rust. And I wonder if you can run the 1000 line OS in C along with the 1000 line hypervisor

It would be nice to see a demo!

LiamPowell

4 months ago

2 replies

How do you define an OS? You can write an EFI "OS" that prints "Hello, world" in approximately 5 lines.

dark-star

4 months ago

that's not an OS, that's an EFI application

spongebobism

4 months ago

It's a bit more than that.

> We'll implement basic context switching, paging, user mode, a command-line shell, a disk device driver, and file read/write operations in C.

see https://1000os.seiya.me/en/

courtcircuits

4 months ago

This repo seems to handle VM exits and memory initialization : https://github.com/soulxu/kvmsample/blob/master/main.c

I'd say it's a good place to start !

arghwhat

4 months ago

1 reply

This is a cool intro to how virtualization instructions work, but people need to understand that it is not revolutionary simplicity or anything like that. It's just a a cool tech demo lacking all the important bits of a modern hypervisor required to make it practical, like paravirtualized drivers for example.

Same when someone claims to have written an OS in 1000 lines and all it does is get you to real mode with VGA graphics and an interactive (but useless) prompt.

(Note that you can benefit from virtualization technology in specialized scenarios outside common hypervisors, but that's not really what's being demoed here.)

ge96

4 months ago

1 reply

Any thoughts on OsakaOS

arghwhat

4 months ago

That it's fine to do things just to have fun an mess around, but thats all there is to it. It's not even an OS at the current state.

Other small OS's are actually OS's and can be impressive efforts. Sometimes they bring new concepts or paradigms, but that itself is rarely more than a curiosity without impact. Still fun though, at the very least for the authors.

giveita

4 months ago

1 reply

Why does it need qemu? Isn't it a qemu?

ahakki

4 months ago

1 reply

I guess because it's a risc-v hypervisor and the author expects you to run it on an x86 machine.

giveita

4 months ago

Thanks. Good use of a turtle. (Turtles all the way down)

nighthawk454