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I never said it was an all or nothing. My point is that trying to handle unexpected errors due to programming error is not safe and Python allows that.

It doesn't matter if throwing ValueError exceptions on sqrt(-1) is well-defined, continuing to run the program by ignoring the exception is no less harmful than silent integer overflows or buffer overruns.

I don't restart my OS when a process crashes because it has been designed to use hardware mechanisms to clean up dead processes. I absolutely do restart my OS when it kernel panics, it doesn't try:except:log:continue.

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Those are hardware mechanisms backed by software that tells the hardware mechanisms what to do. You have a lot of trust in them!

I recently discovered that my Windows machine wouldn't boot because my boot sector had been replaced with some random XML. That's exactly the sort of thing that hardware protection is supposed to prevent - nothing during a normal run of the OS should be writing to the boot sector, at all.

Do you restart your OS when it oopses and kills a process? Linux in fact catches bad memory accesses from kernelspace and attempts to just kill the current process and not the whole kernel.

I trust the code as long as it's behaving correctly, when it encounters a bug I no longer trust it and I shut it down before it can do further harm. A modular HTTP server should do the same.

The OS/process analogy doesn't hold here. The process has completely isolated state from the kernel.

> The OS/process analogy doesn't hold here. The process has completely isolated state from the kernel.

In one direction. That's why I'm asking you if you reboot your machine when your kernel dereferences a wild pointer when executing a system call on behalf a process - in theory it could have corrupted the kernel itself or any process on the system, but Linux makes a practice of trying to just abort execution of the system call, kill the process, and keep going.

If that's what Linux does, that seems fully intentional and the possible consequences on kernel state are probably well-thought out. Are you claiming what Linux does normally is unsafe and could possibly corrupt kernel state? Like every EFAULT? If that's not your claim, then the analogy doesn't hold and you're entirely missing my point.

That is absolutely my claim, and I am absolutely claiming that it is not well-thought-out - it's literally doing this in response to any fault from kernelspace. If you were unlucky enough that the wild pointer referred to someone else's memory, well, sucks to be you, some random process on your system (or random file on disk, or whatever) has memory corruption and nobody even knew.

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