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page fault

What happens when a program touches a page the processor can't use as asked, because it isn't in RAM yet or the access isn't allowed: the processor stops and calls the operating system.

A page fault is the hardware exception raised when translation fails (not-present entry) or a permission check fails; the kernel's handler either fixes the mapping and resumes the faulting instruction or reports an invalid access to the process (Chapter 30).

See also

minor page fault major page fault swap space present bit
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