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Smart pointers for the kernel

(lwn.net)
169 points signa11 | 1 comments | 18 Oct 24 02:10 UTC | HN request time: 0.206s | source
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stonethrowaway ◴[18 Oct 24 03:33 UTC] No.41876123[source]▶
Anyone who wants to do kernel-level development should first do Embedded hardware/software interfacing. No RTOS, plain “Embedded C”, with some bit banging and dealing with voltage spikesc transients and people doing stupid shit to hardware (yes, really) and other things. Know the memory map and recite it from memory. Some might think I’m joking or being facetious - no, I’m pretty serious actually. I’d rather have an embedded person writing kernel drivers in slapped-together C than a Rustacian that complains about unsafe code and being an idiot about it. See [0] for detailed explanation.

People need to learn the niceness of safety and perfect execution is a continuum of tolerances and flimsy guarantees from unmarked silicon that could be made in US, but is most likely a knock off made in China that will fail in 1/3rd of the expected time and gives a false reading if you so much as look at it the wrong way.

[0] https://www.usenix.org/system/files/1311_05-08_mickens.pdf

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jendjdndn ◴[18 Oct 24 05:06 UTC] No.41876508[source]▶
You sound a lot like "kids these days!"

What applicable skills would someone writing a kernel driver gain from reciting a memory map? Abstractions exist for a reason.

The skill is in creating useful an performant abstractions.

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1. exmadscientist ◴[18 Oct 24 07:40 UTC] No.41877153[source]▶
See, I read the parent post's point not as "abstractions are bad" but as "it's much better to be someone who doesn't need the abstraction, but chooses to use it". I have worked with a number of crappy embedded developers in my career. Somehow, the ones who are capable of going beneath the many levels of abstraction are always really, really good at their jobs.

So it's not that embedded Rust is bad. It's that developers who can't do their jobs without embedded Rust are usually very bad indeed. It's great when it's a choice. It's terrible when you lack the skills or perspective to work with what's under the hood.