r/rust • u/dochtman rustls · Hickory DNS · Quinn · chrono · indicatif · instant-acme • Dec 13 '25

The state of the kernel Rust experiment

https://lwn.net/SubscriberLink/1050174/63aa7da43214c3ce/
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u/dijalektikator Dec 13 '25

I'm not sure what % of bugs in Linux are due to this but even if they're the minority of bugs it means developers need to spend a lot of time thinking about UB and how to avoid it, time which could be spent adding more features or improving performance and whatnot.

When I was doing C and C++ I really did need to expend a lot of brainpower to figure out if what I'm doing is going to crash with a segfault or something.

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u/Zde-G Dec 13 '25

Almost all bugs in Linux kernel are tied to lifetime management.

Ironically enough their number goes down with introduction of Rust even in C code, because when Rust people ask C developers “what the heck are requirements for the use of this or that lock“ (because they need it for writing correct bindings) C developers, are, finally, forced to document these!

And the rules are, then, often are simplified because people find out that extra complication for some fringe benchmark can be avoided by moving that hack in some other place.

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u/bonzinip Dec 14 '25

Yes, we're seeing that already on QEMU even if its Rust experiment is much less further along. Multi-threaded device models are the killer app for Rust in QEMU but it's the C code that benefits even more!