Asterinas: OS kernel written in Rust and providing Linux-compatible ABI

Decades ago Linus Torvalds was asked in an interview if he feared Linux to be replaced by something new. His answer was that some day someone young and hungry would come along, but unless they liked writing device drivers Linux would be safe.

This is all paraphrased from my memory, so take it with a grain of salt. I think the gist of it is still valid: Projects like Asterinas are interesting and have a place, but they will not replace Linux as we have it today.

(Asterinas, from what I understood, doesn't claim to replace Linux, but it a common expectation.)

More recently, in a similar vein:

> Torvalds seemed optimistic that "some clueless young person will decide 'how hard can it be?'" and start their own operating system in Rust or some other language. If they keep at it "for many, many decades", they may get somewhere; "I am looking forward to seeing that". Hohndel clarified that by "clueless", Torvalds was referring to his younger self; "Oh, absolutely, yeah, you have to be all kinds of stupid to say 'I can do this'", he said to more laughter. He could not have done it without the "literally tens of thousands of other people"; the "only reason I ever started was that I didn't know how hard it would be, but that's what makes it fun".

https://lwn.net/Articles/990534/

> Hohndel clarified that by "clueless", Torvalds was referring to his younger self

As the saying goes "We do this not because it is easy, but because we thought it would be easy."

Occasionally these are starts of great things.

I feel like there's a potentially large audience for a kernel that targets running in a VM. For a lot of workloads, a simple VM kernel could be a win.

Sometimes, we do such things because it’s hard. We enjoy the challenge. Those that succeed are glad to make it, too.

How is that different from Linux with all virtio drivers? (You can just not compile real hardware drivers)

"You are enthusiastic and write kernel device drivers in rust. Write a device driver for an Intel i350 4 Port gigabit ethernet controller"

I would imagine that virtualized device drivers would have a well-defined api and vastly simplified logic.

I imagine they do. But given that Linux has those simple drivers, why not use them?

Also this mysterious new Fuchsia OS from Google is also shooting for full Linux compatibility and is about to show up in Android, I think this is a much more realistic path of the next generation of operating systems that have a real chance to replace Linux but who knows what their actual plans are here at the moment but I don’t believe for a moment that that project is dead in any way.

Can you give more details about it being used in Android? I thought they started using it in some small devices like nest but haven’t heard anything about Android

Some future VC-funded company will unironically have this same requirement

It wasn't a requirement, it was a prompt :)

Haha damn, it’s so obvious now. I should be asleep.

This is already the reality today with native cloud computing, managed runtimes.

It doesn't matter how the language gets deployed, if the runtime is on a container, a distroless container, or directly running on an hypervisor.

The runtime provides enough OS like services for the programming language purposes.

I wonder if decision for stable syscalls was genius? Like imagine that Linux syscalls will become what C ABI is now. And there will be multiple compatible kernels, so you can choose any and run the same userspace.

but most times, even in such cases, people underestimate or not estimate at all the "hard task they do as a challenge" it's kinda part of the whole thing

It’s about to turn up inside Android running in a VM [1] but it was less clear exactly for what purpose.

My theory is that this is essentially a long term project to bring the core of Chrome OS and Android to rely on Fuschia for its core which gives them syscall level compatibility with what they both use at the moment and that they would both essentially sit as products on top of that.

This is essentially the exact strategy they used if I remember correctly with the Nest devices where they swapped out the core and left the product on top entirely unchanged. Beyond that in a longer term scenario we might also just see a Fuchsia OS as a combined mobile / desktop workstation setup and I think part of that is also why we are seeing ChromeOS starting to take a dependency on Android’s networking stack as well right now.

[1] https://www.androidauthority.com/microfuchsia-on-android-345...