linux - Why do we need kernel space? -


why need separation between kernel space , user space, when every data structure, every memory resource managed kernel if create process in user space? why need such big architecture?

all page tables, context switching etc. managed kernel, why user space? can not use 1 space , develop things on it?

this question may sound weird, want understand why required? if have design new os , not perform such division between kernel space , user space, problem?

thanks

if there no protection between kernel space , user space or between different user processes can write code intentionally or accidentally modify either memory in kernel space or memory in space of user process. old ms-dos lacked protection.


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