cross-posted from: https://lemmy.world/post/25857381
Hellwig is the maintainer of the DMA subsystem. Hellwig previously blocked rust bindings for DMA code, which in part resulted in Hector Martin from stepping down as a kernel maintainer and eventually Asahi Linux as a whole.
Linus ain’t wrong tho
I really appreciated him saying ‘I don’t want yes men, I need people to call me on my bullshit, but I’m calling you out on yours’.
I read through the next few replies, and it seems like the anti-rust maintainer just has an axe to grind and can’t stand people working in a language they don’t understand.
Gee Linus you think you could’ve fucking said something before it got to this point?
Yes but that clearly was not happening. And now they lost a contributor for no reason.
I’d venture to guess this isn’t the first time Linus has had to deal with devs who have ideological disagreements and one quits. It’s not also his job to keep that from happening. What he said is true, there’s a process they have for maintaining Linux, and it doesn’t involve flame wars on social media…it involves flame wars over email 😅.
But seriously, if a devs are going to get upset at each other and rage quit, it’s not Linus’ job to play mediator.
Marcan was probably fed up and was looking for a reason leave. If that’s not the case, then it’s silly for him to just quit mid-discussion, before it’s even become apparent what the reaction to Cristoph Hellwig’s behavior would be and whether his reply would even be taken into account during the review process.
Yah took him long enough and should have never got to this point. Now we have lost a contributer.
People really afraid of Rust out here.
It literally wasn’t about Rust specifically though. Christoph literally said it was about anything that was not C, including assembly, C++, brainfuck, or whatever, entering the kernel. Christoph likes Rust. Christoph (rightfully) does not like mixed language codebases for projects as large and important as Linux
(rightfully) does not like mixed language codebases for projects as large and important as Linux
You make it sound like it’s a matter of taste rather than a technical one (and I suspect it actually might be just about taste in the end)
Its a little of column A, little of column B type situation.
Yes, some of it is his taste, but that taste is coming from a technical place. Primarily long term maintainability of the project.
I realize what Linus came out and said outlines that no code is entering Christoph’s part of the project, but Christoph is playing goalie and needs to make sure that never happens in order to keep everything working correctly for a very long time.
Maybe the DMA module gets rewritten completely in Rust one day, but until then, rust modules interfacing with a C-only component seems to be the best for long-term maintenance.
It appears so now, yes, but when the drama initially came out it sounded like they were asking for a tiny amount of rust in the kernel to make it work, or if not rust, changing the C to tailor it specifically to the rust. Which I think is a reasonable thing to be concerned about from a maintainability perspective long-term, especially if the rust developers decide to leave randomly (Hector’s abrupt quitting over this very issue is a prime example).
Yea but if someone uses those bindings then you can’t just not support it.
By the time this code gets into a large scale production system it will be 2029. That is when the bugs will come in if someone leveraged the Rust bindings.
You can ask the big company users at that time to contribute their fixes upstream, but if they get resistance because they have relatively junior Rust devs trying to push up changes that only a handful of maintainers understand, the company will just stop upstreaming their changes.
The primary concern that a major open source project like this will have is that the major contributors will decide that interacting with it is more trouble than it is worth. That is how open source projects move to being passion projects and then die when the passion dies.
Rust is straight up better than C. It’s safer and less prone to errors.
It’s not feasible to convert the entire Linux codebase at once. So your options are to either have a mixed codebase, or stick with effectively Cobol into 2020.
Rust is great, but you are not thinking from a long-term project perspective. Rust is safer, but Linux needs to be maintainable or it dies.
Based on what you’re saying, the only way its going to reasonably be converted to Rust is if someone forks Linux and matches all the changes they’re making in C as they happen but converts it all to Rust. Once its all converted and maintainability has been proven, a merge request would need to be made.
I can relate. I can emphasize with someone who’s learned every nuance of a language, and after 30-40 years suddenly these kids come in with their strange hieroglyphics slowly replacing everything you’ve worked on.
A lot of people commenting on this seem to have gaps in their knowledge of what happened. I highly recommend reading the linked email, as it is both short and has valuable context.
Is there an easy way of seeing the preceding emails in a threaded format?
I read some posted yesterday that were related but it’s damn confusing whether the conversation has been active in between?
Anyone got more context on this I can read through? I haven’t kept up with this other than Linus’s notorious attitude.
Someone submitted some code to the Linux kernel. One of the maintainers repeatedly denied it for no reason other than it contained code that is not C. A different contributor became very angry, lashed out publicly on social media, accused the maintainer of sabotaging R4L for no technical reason, then removed themselves from the project. They were also the founder of Asahi Linux and resigned from that as well.
It’s nothing to do with Rust, specifically.
Marcan is not the submitter. Unless I’ve missed something, the submitter is still working on the patch.
Yeah that is a very opinionated description. Up until “the submitter became very angry, lashed out” that sounds about right, but from there on, your bias shows. Which is fine, and human, but probably worth mentioning this to others reading this. It’s not exactly an objective view, whatever that’s worth.
It’s mostly in that linked thread. The high level of it is a guy wanted to push Rust code. The maintainer said no it would mean the API for this would be tied to Rust and that is unacceptable. It cause another big contributer to throw a fit and Linus said he can’t be everyone’s mom. They kept fighting for like 2 months apparently? Now Linus stepped in, looked at the code and said the Rust code clearly doesn’t impact the API in the way the maintainer was saying it just breaks itself if the maintainers allow changes to the API.
I kinda dislike the idea that it’s cool for people to contribute code that is so easy to break. I have a feeling after it happens a few times they are going to claim that it is being done intentionally and that the slap fights will carry on.
I do not know why you say it is easy to break.
The Rust team are maintaining their side. I do not expect it to break. And the C code that the Rust code depends on is used by lots of other code. It should be a stable interface. Changing the C code just to break the Rust code would break a lot of C code too and upset a lot of folks.
And the who point is to create a more idiomatic interface on the Rust side. So, even if the c interface does change, it may only be a small amount of Rust code that needs to change in response.
I can understand Hellwig’s fear, though.
From what I gather as a bystander, it’s apparently common that a refactoring in your module that breaks its API will involve fixing all the call-sites to keep the effort on the person responsible for the change. Now the Rust maintainers say “it’s fine; if it breaks, we’ll deal with it” which is theoretically takes away the cross-language issue for the C-maintainer. Practically I can very well see, that this will still cause friction in the future.
Let’s say such a change happens and at that time there’s a bit of time pressure and the capacity on the rust maintainers is thing for whatever reasons. Will they still happily swallow that change or will they start to discuss if it’s really necessary to do that change? And suddenly, the C-maintainer has a political discussion on top of the technical issue they wanted to solve.
As someone who just wants to get shit done, I would definitely have that fear.
(That doesn’t mean it’s still a bullet not worth swallowing. The change overall can still be worth the friction. I am just saying that I think it’s not totally unwarranted that a maintainer feels affected by this even though current pledges from the other parties promise otherwise; this stance can change or at least be challenged over and over.)
Yea and if the Rust developers don’t show up to the show? Rust is a baby and it has done so little on its own. This isn’t a neat little side project, this is code that a major vendor will want to take up and will demand be maintained. There are implications on a global scale.
Thanks for the summary, I did a bit of reading myself. It’s interesting the dynamics at play here - you’ve got a long, long term contributor in Hellwig who’s been a maintainer since before Rust even existed, then you’ve got quite a few people championing Rust being introduced into the kernel. I feel like Hellwig’s concerns must have more to do with the long term sustainability of the Rust code - like will there be enough Rust developers 10, 20, 30 years down the line. I mean, even if it stays maintained, having multiple languages in a codebase increases complexity and makes it harder to contribute. Then you have Filho resigning from the Rust for Linux project, which in itself kind of calls into question the long term sustainability of the project. It seems like Rust would have quite a few benefits for the Linux kernel, but the question remains of if it’s still gonna be any good in a few decades. This is juicy stuff!