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page table entry

One line of a page table: where in RAM one page lives, plus yes/no flags saying whether it is there and what may be done with it.

A page table entry (8 bytes on x86-64, ARM64 and RV64) holds a physical frame number and flag bits: present/valid, writable, user-accessible, no-execute, accessed and dirty, plus caching and software-defined bits.

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