GATE CSE 2024 | Set 2 | Question: 14

Question

​Which of the following tasks is/are the responsibility/responsibilities of the memory management unit $\text{(MMU)}$ in a system with paging-based memory management?

• A. Allocate a new page table for a newly created process
• B. Translate a virtual address to a physical address using the page table
• C. Raise a trap when a virtual address is not found in the page table
• D. Raise a trap when a process tries to write to a page marked with read-only permission in the page table

Answer 1

A: False

The OS or Kernel provides page tables, and the MMU uses the page tables to translate virtual addresses into physical addresses for the OS.

Source: https://stackoverflow.com/a/58996725

B: True
This is Main Function of MMU

C: True
MMU will raise the trap when the Valid bit says invalid.
Source: Q13 at https://www.cse.iitb.ac.in/~mythili/os/ps/memory/ps-memory.pdf

D: True
MMU will raise the trap when the process tries to write but protection bit says "read-only"
Source: Q2c, Page 3, https://student.cs.uwaterloo.ca/~cs350/common/old-exams/F11-midterm-sol.pdf