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A comment on The wild world of non-C operating systems. Parent comment

Re:The wild world of non-C operating systems by imtringued on Friday April 01, 2022 @05:42AM (#30876548)
Isn't it still possible to cause corruption within Java? If your operating system is written in Java it will have some unsafe interfaces where programmer, hardware or concurrency bugs will then let you bypass security features.

Yes this is a problem with all operating systems and it is much less likely with Java compared to C but it feels to me like you are entirely reliant on the JVM producing "verified" code. It's kinda like how the Rust gang has to do formal verification to prove that their borrow checker is actually water tight instead of just acting as if the programmer made sure it is water tight like in C land.

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Re:The wild world of non-C operating systems by mike_hearn on Tuesday April 05, 2022 @04:33AM (#30916601)
Yes, it gets you a long way but then on top you need things like IOMMUs to stop a driver mis-programming a hardware device and evading the memory safety that way. Fortunately all modern platforms have IOMMUs.

The point of managed code is that it compresses the space where (memory) safety problems can creep in to a small core in the runtime, which gets really well tested and reviewed. Even if there are concurrency bugs in your user-level code they can't corrupt memory in the manner C code can do - just yield objects in an invalid state that will hopefully be detected and cause exceptions very quickly. In turn you can then recover and try again or let the user know. CoModExceptions are a good example of that in action.

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