Implementing protection with virtual memory, Computer Engineering

Assignment Help:

Implementing Protection with Virtual Memory - computer architecture:

To enable the operating system to implement protection in the VM system, the HW have to:

I. Support at least 2 modes that denoted whether the running process is a user process (executive process) or an operating system process (kernel/supervisor process).

II. Provide a part ion of the CPU state that a user process may read but not write (includes supervisor mode bit).

  • Provide mechanism where the CPU may go from user mode to supervisor mode (accomplished by a system call exception) and vice versa (return from exception instruction).

o   Only operating system process may change page tables. Page tables are held in operating system address space thereby preventing a user procedure from changing them. 

o   When processes desire to share information in a restricted way, the OS have to assist them.

o   The write access bit (in both the TLB and the page table) can be used to limit the sharing to only read sharing.

 


Related Discussions:- Implementing protection with virtual memory

How does tcp achieve reliability, How does TCP achieve reliability? One...

How does TCP achieve reliability? One of the most significant technologies is retransmission. While TCP stands data the sender compensates for packet loss through implementing

Assembler directives, Assembler directives: An assembler directive is ...

Assembler directives: An assembler directive is a statement to give direction to the assembler to perform the task of assembly process. Assembler directives control organizati

Describe the interpretation features of vba, VBA is licensed to Microsoft a...

VBA is licensed to Microsoft and this compatible with and only Microsoft products. Code written is compiled by an intermediate language known as P-code and this is stored in hostin

Programs, A palindrome is a string that reads the same from both the ends. ...

A palindrome is a string that reads the same from both the ends. Given a string S convert it to a palindrome by doing character replacement. Your task is to convert S to palindrome

Illustrate working of asynchronous counters, Q. Illustrate working of Async...

Q. Illustrate working of Asynchronous Counters? This is more frequently referred as ripple counter as the change that takes place in order to increment counter ripples through

Discuss the 5-level switching hierarchy recommended by ccitt, Discuss the 5...

Discuss the 5-level switching hierarchy recommended by CCITT. Hierarchical networks are able of handling heavy traffic where needed, and at similar time use minimal number of t

Visualization, Visualization Visualization is a general method in contr...

Visualization Visualization is a general method in contract to search based tools.  In this method visual aids are given like pictures to assist the programmer in evaluating th

Risks by financial service provider perspective, What are the risks by fina...

What are the risks by financial service provider's perspective in Electronic Payment Systems? Through the financial service provider's perspective: • Stolen service or c

Explain bootp (boot strap protocol), Explain BOOTP (Boot Strap Protocol). ...

Explain BOOTP (Boot Strap Protocol). TCP or IP designer observed that several of the configuration steps could be combined in a single step if a server was capable to supply mo

Interpolation algorithm, Design two matlab algorithms for enlarging the 256...

Design two matlab algorithms for enlarging the 256x256 images into 512x512 images by using bilinear and bicubic interpolations   a)  Evaluate the interpolated images with the

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd