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

Input-output-processor interconnection network (iopin), Input-Output-Proces...

Input-Output-Processor Interconnection Network (IOPIN) This interconnection network is used for communication between I/O channels and processors. All processors commune with a

Or-introduction rule, Or-Introduction : Thus if we know about one thin...

Or-Introduction : Thus if we know about one thing is true, and also we know that a sentence when there thing is in a disjunction is true. Here if we consider example, like we

Smugglers problem, #question.Smugglers are becoming very smart day by day. ...

#question.Smugglers are becoming very smart day by day. Now they have developed a new technique of sending their messages from one smuggler to another. In their new technology, the

What are the difference between heap and stack, What are the difference bet...

What are the difference between heap and stack? The Stack is more or less responsible for maintaining track of what's executing into our code or what's been "called". The Heap

Determine the objectives of object oriented analysis, Objectives of object ...

Objectives of object oriented analysis After going through this unit, you should be able to: define the concepts of the objects in the system; express desired syste

What is multiprogramming, What is multiprogramming or multitasking? The...

What is multiprogramming or multitasking? The operating system manages the concurrent implementation of several application programs to make the best possible uses of computer

Computer networks, distributed & centralized system in computer network

distributed & centralized system in computer network

Decision tree learning for cancer diagnosis, Assignment 1: Decision tree le...

Assignment 1: Decision tree learning for cancer diagnosis In this mini-project, you will implement a decision-tree algorithm and apply it to breast cancer diagnosis. For each p

Function of in network access layer in tcp/ip protocol stack, What is the f...

What is the function of in network access layer in TCP/IP protocol stack? Function of Network Access Layer: The network access layer is the lowest layer within Internet

Logic-based expert systems, Logic-based Expert Systems : Expert system...

Logic-based Expert Systems : Expert systems are agents that are programmed to make decisions just about real world situations are place together by utilising knowledge illicit

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