operating system - What is the difference between the kernel space and the user space? -

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what difference between kernel space , user space? kernel space, kernel threads, kernel processes , kernel stack mean same thing? also, why need differentiation?

the really simplified answer kernel runs in kernel space, , normal programs run in user space. user space form of sand-boxing -- restricts user programs can't mess memory (and other resources) owned other programs or os kernel. limits (but doesn't entirely eliminate) ability bad things crashing machine.

the kernel core of operating system. has full access memory , machine hardware (and else on machine). keep machine stable possible, want trusted, well-tested code run in kernel mode/kernel space.

the stack part of memory, naturally it's segregated right along rest of memory.


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