I appreciate that his anger is still there, its just worded differently, in a more modern (softer) attack. Is this still how we control developers in 2025? Yes! Deal with it or go fork it yourself. The day this goes away is the day Linux begins to die a death of 1,000,000 cuts in code quality.
That's a huge sacrifice when speaking of him, which we must appreciate. But to be honest, I must agree with his point of view.
Golden rule when developing projects is to stick to one (the least amount possible of) technology, otherwise, you'll end up with software for which you need to hire developers of different languages or accept the developers that won't be experts in some of them. I am working on a project that, up until a year ago, had been partly written in Scala. All the Java developers who didn't know Scala were doomed to either learn it in pain (on errors and mistakes) or just ignore tasks regarding that part of the system.
Multiple years later, what was the state of things? We had a portion of the codebase in Kotlin with dedicated native/Kotlin developers, and a portion of the codebase in RN with dedicated RN/JS developers.
Any time there's a bug it's a constant shuffle between the teams of who owns it, which part of the code, native or JS the bug is coming from, who's responsible for it. A lot of time time nobody even knows because each team is only familiar with part of the app now.
The teams silo themselves apart. Each team tries its best to hold on to the codebase - native teams tries to prevent JS team from making the whole thing JS, the JS team tries to covert as much to JS as possible. Native team argues why JS features aren't good, JS team argues the benefits over writing in native. Constant back and forth.
Now, no team has a holistic view of how the app works. There's massive chunks of the app that some other team owns and maintains in some other language. The ability to have developers "own" the app, know how it works, have a holistic understanding of the whole product, rapidly drops.
Every time there's a new feature there's an argument about whether it should be native or RN. Native team points out performance and look-and-feel concerns, RN team points out code sharing / rapid development benefits. Constant back and forth. Usually whoever has the most persuasive managers wins, rather than on technical merit.
Did we end up with a better app with our new setup, compared to one app, written in one language, with a team of developers that develop and own and know the entire app? No, no I don't think so.
Feels like pretty parallel of a situation compared to Rust/C there.
I have worked on lots of cross language codebases. While it’s extremely useful to have experts in language or part, one can meaningfully contribute to parts written in other languages without being an expert. Certainly programmers on the level of kernel developers should readily be able to learn the basics of Rust.
There’s lots of use cases for shared business logic or rendering code with platform specific wrapper code, e.g. a C++ or Rust core with Swift, Kotlin, and TypeScript wrappers. Lots of high level languages have a low level API for fast implementations, like CPython, Ruby FFI, etc. The other way around lots of native code engines have scripting APIs for Lua, Python, etc.
Anyway, I’m a bit of a Rust fanboy, and would generally argue that its use in kernel and other low-level applications is only a net benefit for everyone, and doesn’t add much complexity compared to the rest of these projects. But I could also see a 2030 version of C adding a borrow checker and more comparable macro features, and Rust just kind of disappearing from the scene over time, and its use in legacy C projects being something developers have to undo over time.
What makes this interesting is that the difference between C code an Rust code is not something you can just ignore. You will lose developers who simply don't want or can spend the time to get into the intricacies of a new language. And you will temporarily have a codebase where 2 worlds collide.
I wonder how in retrospect they will think about the decisions they made today.
Or just using those kernel APIs, period.
gccrs will allow the whole thing to be built with GCC toolchain in a single swoop.
If banks are still using COBOL and FORTRAN here and there, this will be the most probable possibility in my eyes.
I suppose the biggest reason is that C programmers are more likely than not trained to kinda know what the assembly will look like in many cases, or have a very good idea of how an optimizer compiler will optimize things.
This reminds me I need to do some non-trivial embedded project with Rust to see how it behaves in that regard. I'm not sure if the abstraction gets in the way.
The decision was not made today, what happens today (or, rather, a few days ago) is Linus calling out a C maintainer going out of his way to screw rust devs. Rust devs have also been called out for shitty behaviour in the process.
The decision to run a Rust experiment is a thing that can be (and is) criticized, but if you allow people to willfully sabotage the process in order to sink the experiment, you will also lose plenty of developers.
As for your concern about code quality, it's the exact same situation that already exists today. The maintainer is responsible for his code, not for the code that calls it. And the Rust code, is just another user.
What if you're in a world where Rust code is either a significant or primary consumer of your interface ... surely as the API designer, you have to take some interest in how your API is consumed.
I'm not saying you become the owner of Rust bindings, or that you have to perform code-reviews, or that you have veto power over the module .. but you can't pretend Rust doesn't exist.
Sometimes the other team proves incompetent and you are forced to do their job. However that is an unusual case. So trusting other teams to do their job well (which includes trying something you don't like) is a good rule.
Yes. This is exactly what it is. It is a "pragmatic compromise" to side-step major internal cultural and philosophical issues (not technical issues). You're basically telling a number of C maintainers that they can simply pretend Rust doesn't exist, even if it may be the case that Rust code is the primary consumer of that API. That's a workable solution, but it isn't an ideal solution - and that's a little sad.
So if someone wants to write software in Rust that just uses the DMA driver, that should be fine. Linus is entirely in the right.
Yes. And that involves not completely ignoring an entire universe of consumers of your API, *as a general policy*. This is especially true with modules that may have Rust code as the primary consumer of the API.
I admit, I don't know what not ignoring Rust code by maintainer means in practice, and I agree it shouldn't mean that the C maintainer code-reviews the Rust bindings, or has veto power over the entire Rust module, or that the maintainer vets the architecture or design of the Rust module, or is on the Rust module mailing list. But it also shouldn't be that as a *general policy*, the C maintainer does not take any interest in how the API is consumed by Rust, and worse, pretends Rust doesn't exist.
>So if someone wants to write software in Rust that just uses the DMA driver, that should be fine.
That part is sensible. Did I argue otherwise?
starts writing business plan while installing CMake
I hate it so much when people assume they are smart and workaround issue at other end of interface. It always end up that you need to understand both the workaround and original bug or you can't even read it.
And Hellwig works as a contractor, he's not a volunteer in the same way that Con Kolivas was. Hellwig isn't truly independent either.
Especially those mailing list, engineering marvel, indeed!
Why would you say something like that?
From the e-mail [0] the article is based on:
> The fact is, the pull request you objected to DID NOT TOUCH THE DMA LAYER AT ALL.
> It was literally just another user of it, in a completely separate subdirectory, that didn't change the code you maintain in _any_ way, shape, or form.
If enough people get behind a Rust OS, it could leapfrog Linux. I guess people just don't dream big anymore.
That's a good thing. This will test rust's reliability.
The "free" part in free software is not just free in beer, it's also free in freedom. That little bit gets forgotten. People work on it because they want to, not because they have to. If a developer does not want to use Rust, they can and should not be forced to. It does not matter if Rust is objectively safer, or better, or any of the purported arguments. Forcing it eliminates the freedom of choice.
The Rust folks should make their own kernel and OS. Let it compete directly with Linux. In open source, this is the way.
