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

Link your documents to site, Images in the top area of Compass home page gu...

Images in the top area of Compass home page guide visitors to specific pages on the site. Now you will add links for navigation buttons. You will see that there are some ways to

Hubs are present in the network, Hubs are present in the network To inte...

Hubs are present in the network To interconnect the LAN with WANs.

Mingw32 compiler, Although there are no compulsory "c" compiler for this su...

Although there are no compulsory "c" compiler for this subject, but the compiler we are going to use for this example is the Mingw32 compiler. Download the source code files fro

Kirchoff''s laws, i want to make an assignment about kirchoff''s law

i want to make an assignment about kirchoff''s law

Define the pulse-triggered (master-slave) flip-flops, Define the Pulse-Trig...

Define the Pulse-Triggered (Master-Slave) Flip-flops? The term pulse-triggered signify that data are entered into the flip-flop on the rising edge of the clock pulse, though th

Explain about cseg segment, CSEG SEGMENT  ASSUME CS:CSEG, DS:CSEG, SS:CS...

CSEG SEGMENT  ASSUME CS:CSEG, DS:CSEG, SS:CSEG  ORG 100h START:MOV AX, CSEG; Initialise data segment  MOV DS, AX; register using AX  MOV AL, NUM1; Take the first num

Explain binary number system, Explain Binary number system. Ans. Bi...

Explain Binary number system. Ans. Binary Number System The number of system along with base or Radix two is termed as the Binary Number System. To show the number, 0 a

Explain the working of a 3-bit D/A converter, With the help of R-2R binary ...

With the help of R-2R binary network, explain the working of a 3-bit D/A converter and derive an expression for the output voltage. Ans: We see a 3-bit R-2R ladder D/A netwo

Why is the data bus in most microprocessors bidirectional, Why is the data ...

Why is the data bus in most microprocessors bidirectional while the address bus is unidirectional?  Data Bus:  These lines are used to send data to memory by output ports and

Learn synchronization principles, Q. Learn synchronization principles? ...

Q. Learn synchronization principles? To learn synchronization subsequent dependencies are recognized:  i)  Data Dependency: These are RAW, WAW and WAR dependency.  ii) Co

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