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Enable Basic Paging in Protected Mode

hard4/8

Set Up the Interrupt Descriptor Table in Protected Mode Run Real Mode Code with Virtual 8086 Mode

Language

Compiler

2.0s Limit 256MB

Submit and pass all tests to enable saving to GitHub.

Implementation

Implement basic paging setup in C.

Requirements:

Define page directory and page table structures
Implement set_page_directory_entry() and set_page_table_entry()
Identity map first 4MB of memory
Show virtual address split into PD index, PT index, offset
Implement virtual_to_physical() translation
Show CR3 being loaded
Enable paging by setting CR0.PG
Handle page fault conceptually
Print page walk for sample addresses
Show mapping table

Test:

Show page directory created
Show page table entries
Show address translation
Show paging enabled
Show page fault concept

Why This Matters

The identity-mapped page directory and page table you build here is the exact bootstrap step every real kernel — Linux's arch/x86/mm/init.c included — performs so the CPU keeps executing its own code the instant CR0.PG flips on. Skipping the identity map of the currently-running code is a classic bug: the very next instruction after enabling paging triple-faults because its physical address is no longer mapped to any virtual address.

Hints

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Validation Suite

main.c

Workspace 1.0

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