for a single task in protected mode, the 80386 can address ... · ((marks)) (1/2/3...) 1...

((MARKS))

(1/2/3...)

1

((QUESTION)) For a single task in protected mode, the 80386 can address-------Vitual memory the virtual memory of Virtual memory

((OPTION_A)) 32 GB

((OPTION_B)) 64 MB

((OPTION_C)) 32 TB

((OPTION_D)) 64 TB

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The mechanism to provide protection, that is accomplished

with the help of read/write privileges is with the help of read/write

((OPTION_A)) restricted use of segments

((OPTION_B)) restricted accesses to segments

((OPTION_C)) privileged instructions

((OPTION_D)) privileged operations

((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The mechanism that is accomplished using descriptor usages

limitations, and rules of privilege check is

((OPTION_A)) privileged instruction check

((OPTION_B)) operation reference check

((OPTION_C)) segment load check

((OPTION_D)) none of the mentioned

((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The mechanism that is executed at certain privilege levels, determined by CPL (Current Privilege Level) and I/O privilege level (IOPL) is



((OPTION_C)) privileged instructions or operations


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The paging unit is enabled only in

((OPTION_A)) virtual mode

((OPTION_B)) addressing mode

((OPTION_C)) protected mode


((CORRECT_C

HOICE))

(A/B/C/D)

c

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The bit that is used for providing protection is

((OPTION_A)) User/Supervisor bit

((OPTION_B)) Read bit

((OPTION_C)) Write bit

((OPTION_D)) all of the mentioned

((CORRECT_C

HOICE))

(A/B/C/D)

d

((EXPLANATI

ON))

(OPTIONAL)

The User/Supervisor (U/S) bit and Read/Write (R/W) bit are used

to provide protection

((MARKS))

(1/2/3...)

1

((QUESTION)) To enter in protected mode,____________ bit should be at logic 1.

((OPTION_A)) PG

((OPTION_B)) ET

((OPTION_C)) PE

((OPTION_D)) NT

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) In 80386, privilege levels are defined by _______

((OPTION_A)) DPL

((OPTION_B)) CPL

((OPTION_C)) RPL

((OPTION_D)) All of above

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI)

) (OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) How many privilege levels are available in 80386

((OPTION_A)) 1

((OPTION_B)) 2

((OPTION_C)) 3

((OPTION_D)) 4

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((MARKS))

(1/2/3...)

1

((QUESTION)) Which is highest privilege level in 80386

((OPTION_A)) 1

((OPTION_B)) 3

((OPTION_C)) 2

((OPTION_D)) 0

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) Which is LOWEST privilege level in 80386

((OPTION_A)) 1

((OPTION_B)) 0

((OPTION_C)) 3

((OPTION_D)) 2

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI)

) (OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The unit that provides a four level protection mechanism, for system‟s

code and data against application program is

((OPTION_A)) central processing unit

((OPTION_B)) segmentation unit

((OPTION_C)) bus interface unit


((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI)

) (OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) In protected mode of 80386, the VM flag is set by using

((OPTION_A)) IRET instruction

((OPTION_B)) task switch operation

((OPTION_C)) IRET instruction or task switch operation


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI)

) (OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The task privilege level at the instant of execution is called

((OPTION_A)) Descriptor privilege level (DPL)

((OPTION_B)) Current privilege level (CPL)

((OPTION_C)) Effective privilege level (EPL)


((CORRECT_CH B

((MARKS))

(1/2/3...)

1

((QUESTION)) By using privilege mechanism the protection from unauthorised

accesses is done to

((OPTION_A)) operating system

((OPTION_B)) interrupt handlers

((OPTION_C)) system softwares


((CORRECT_CHO

ICE)) (A/B/C/D)

D

((EXPLANATIOPT

IONAL)

OICE)) A/B/C/D)

((EXPLANATIO

N)) (OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) Once the CPL is selected, it can be changed by

((OPTION_A)) HOLD

((OPTION_B)) transferring control using system descriptors

((OPTION_C)) transferring control using gate descriptors

((OPTION_D)) transferring control using interrupt descriptors

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The data segments defined in GDT (global descriptor table) and the LDT

(local descriptor table) can be accessed by a task with

((OPTION_A)) privilege level 0

((OPTION_B)) privilege level 1

((OPTION_C)) privilege level 2

((OPTION_D)) privilege level 3

((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) A task with privilege level 0, does not refer to all the lower level privilege

descriptors in

((OPTION_A)) GDT (global descriptor table)

((OPTION_B)) LDT (local descriptor table)

((OPTION_C)) IDT (interrupt descriptor table)


((CORRECT_C

HOICE))

B

(A/B/C/D)

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The selector RPL that uses a less trusted privilege than the current

privilege level for further use is known as

((OPTION_A)) Least task privilege level

((OPTION_B)) descriptor privilege level

((OPTION_C)) effective privilege level


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The effective privilege level is

((OPTION_A)) maximum numeric of RPL and CPL

((OPTION_B)) minimum privilege of RPL and CPL

((OPTION_C)) numeric minimum and privilege maximum of RPL and CPL


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The task requesting an access to a descriptor is allowed to access after

checking the

((OPTION_A)) type of descriptor

((OPTION_B)) privilege level

((OPTION_C)) type of descriptor and privilege level

((OPTION_D)) corresponding segment

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) A CALL instruction can reference only a code segment descriptor with

((OPTION_A)) DPL less privilege than CPL

((OPTION_B)) DPL equal privilege to CPL

((OPTION_C)) DPL greater privilege than CPL


((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The RPL of a selector that referred to the code descriptor must have

a)

b) c) d)

((OPTION_A)) less privilege than CPL

((OPTION_B)) greater privilege than CPL

((OPTION_C)) equal privilege than CPL

((OPTION_D)) any privilege regarding CPL

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The instruction that refers to only code segment descriptors with DPL

equal to or less than the task CPL is

((OPTION_A)) CALL

((OPTION_B)) IRET

((OPTION_C)) ESC

((OPTION_D)) RET and IRET

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) By using privilege mechanism the protection from unauthorised accesses

is done to

((OPTION_A)) operating system

((OPTION_B)) interrupt handlers

((OPTION_C)) system softwares


((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The mechanism to provide protection, that is accomplished with the help

of read/write privileges is



((OPTION_C)) privileged instructions

((OPTION_D)) privileged operations

((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The mechanism that is accomplished using descriptor usages limitations,

and rules of privilege check is

((OPTION_A)) privileged instruction check

((OPTION_B)) operation reference check

((OPTION_C)) segment load check


((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The mechanism that is executed at certain privilege levels, determined by

CPL (Current Privilege Level) and I/O privilege level (IOPL) is



((OPTION_C)) privileged instructions or operations


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) If CPL is not of the required privilege level, then the instructions that get

affected is

((OPTION_A)) IRET

((OPTION_B)) POPF

((OPTION_C)) IRET and POPF


((CORRECT_C

HOICE))

C

(A/B/C/D)

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) If CPL is greater than zero, then the instruction that remains unaffected is

((OPTION_A)) IRET

((OPTION_B)) POPF

((OPTION_C)) IRET and POPF


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The condition, “CPL not equals to zero” satisfies, when executing the

instruction

((OPTION_A)) LIDT

((OPTION_B)) LGDT

((OPTION_C)) LTR


((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) While executing the instruction IN/OUT, the condition of CPL is

((OPTION_A)) CPL = 0

((OPTION_B)) CPL < IOPL

((OPTION_C)) CPL > IOPL


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The instruction that reads the segment limit into the register, if privilege

rules and descriptor type allow is

((OPTION_A)) VERW

((OPTION_B)) APRL

((OPTION_C)) LSL

((OPTION_D)) LAR

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The instruction that adjusts the RPL (Requested Privilege Level) of the

selector, to the numeric maximum of current selector RPL value is

((OPTION_A)) LAR

((OPTION_B)) VERR

((OPTION_C)) LSL

((OPTION_D)) APRL

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) The selector RPL that uses a less trusted privilege than the current

privilege level for further use is known as

((OPTION_A)) Least task privilege level

((OPTION_B)) descriptor privilege level

((OPTION_C)) effective privilege level


((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) Amongst the given which is not a privilege instruction?

((OPTION_A)) CLTS

((OPTION_B)) TEST

((OPTION_C)) HLT

((OPTION_D)) LLDT

((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) Amongst the given which is a privilege instruction?

((OPTION_A)) LMSW

((OPTION_B)) TEST

((OPTION_C)) AND

((OPTION_D)) STD

((CORRECT_C

HOICE))

(A/B/C/D)

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) Amongst the given which is a privilege instruction?

((OPTION_A)) AAA

((OPTION_B)) OR

((OPTION_C)) CLD

((OPTION_D)) MOV CR3, EAX

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

((QUESTION)) What is the significance of setting R/W field of PDE in protected

mode?

((OPTION_A)) (a) Write privileges are allowed from PL3 code

((OPTION_B)) (b) Write privileges are allowed from PL2 code

((OPTION_C)) (c) Write privileges are allowed from PL1 code

((OPTION_D)) (d) Write privileges are allowed from PL0 code

((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

((QUESTION)) What is the significance of setting R/W field of PTE in protected mode?

((OPTION_A)) (a) Write privileges are allowed from PL3 code

((OPTION_B)) (b) Write privileges are allowed from PL2 code

((OPTION_C)) (c) Write privileges are allowed from PL1 code

((OPTION_D)) (d) Write privileges are allowed from PL0 code

((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) What privilege level must be assigned to Kernel?

((OPTION_A)) PL0

((OPTION_B)) PL1

((OPTION_C)) PL2

((OPTION_D)) PL3

((CORRECT_C

HOICE))

(A/B/C/D)

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) What condition must be satisfied for successful control transfer using Call

Gate mechanism?

((OPTION_A)) (a) Target DPL= >Max(RPL, CPL) <= Gate DPL

((OPTION_B)) (b) Target DPL<= Max(RPL, CPL) => Gate DPL

((OPTION_C)) (c) Target DPL=> Max(RPL, CPL) => Gate DPL

((OPTION_D)) (d) Target DPL<= Max(RPL, CPL) <= Gate DPL

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) For instruction HLT to be executed what must be the value of CPL?

((OPTION_A)) 0

((OPTION_B)) 1

((OPTION_C)) 2

((OPTION_D)) 3

((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

Conforming Code segment

((QUESTION))

((OPTION_A))

((OPTION_B))

((OPTION_C))

((OPTION_D))

((CORRECT_C

HOICE))

(A/B/C/D)

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

The on chip protection hardware performs which checks of the following

?

((QUESTION)) Type and Limit check

((OPTION_A)) Restriction of Procedure Entry points

((OPTION_B)) Restriction of addressable DOMAIN

((OPTION_C)) Restriction on Certain Instruction Execution


((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

((QUESTION)) System services are implemented at Privilege level -----

((OPTION_A)) 0

((OPTION_B)) 1

((OPTION_C)) 2

((OPTION_D)) 3

((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) Custom routines to support special purpose system operations like Device

Drivers are executed at Privilege level ----

((OPTION_A)) 0

((OPTION_B)) 1

((OPTION_C)) 2

((OPTION_D)) 3

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) Inter privilege level transfer can be done using

((OPTION_A)) Task gate Descriptor

((OPTION_B)) Call Gate Descriptor

((OPTION_C)) Conforming Code segment Descriptor

((OPTION_D)) B AND C

((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

((QUESTION)) Conforming Code Segments conforms the privilege level of -----

((OPTION_A)) Caller – calling code

((OPTION_B)) Callee – called code

((OPTION_C)) Both A and B

((OPTION_D)) None of above

((CORRECT_C

HOICE))

(A/B/C/D)

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) For Conforming Code Segments to be used Rule is

((OPTION_A)) CPL =DPL & C bit = 1

((OPTION_B)) CPL numerically > DPL & C bit = 1

((OPTION_C)) CPL numerically < DPL & C bit = 1


((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) Call gate is used to access --------

((OPTION_A)) Code at same Privilege level

((OPTION_B)) Code at higher privilege level

((OPTION_C)) Code at lower Privilege


((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) Privilege requirements to use a call gate are -------------- (numerically)

((OPTION_A)) CPL ≤ DPL of the Code & C bit=0

((OPTION_B)) DPL of the target code segment ≤ CPL & C bit=0

((OPTION_C)) Target DPL ≤ max (RPL,CPL) & C bit=0


((CORRECT_C

HOICE))

(A/B/C/D)

D

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) Type field of Call gate indicates value - -------------

((OPTION_A)) S=0 and Type = 1100

((OPTION_B)) S=1 and Type = 1100

((OPTION_C)) S=0 and Type = 0100


((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

1

((QUESTION)) Destination Selector field of a call gate is ------- bits long

((OPTION_A)) 8

((OPTION_B)) 16

((OPTION_C)) 32

((OPTION_D)) 48

((CORRECT_C

HOICE))

(A/B/C/D)

B

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) Destination offset field of a call gate is ------- bits long

((OPTION_A)) 8

((OPTION_B)) 16

((OPTION_C)) 32

((OPTION_D)) 48

((CORRECT_C

HOICE))

(A/B/C/D)

C

((EXPLANATI

ON))

(OPTIONAL)

((MARKS))

(1/2/3...)

2

((QUESTION)) WC field of call gate is used to push ------- on destination privilege level

stack .

((OPTION_A)) Old stack SS:ESP and old CS:EIP

((OPTION_B)) New stack SS:ESP and old CS:EIP

((OPTION_C)) Both SS:ESP and old CS:EIP


((CORRECT_C

HOICE))

(A/B/C/D)

A

((EXPLANATI

ON))

(OPTIONAL)

(MARKS)) (1/2/3...)

1

((QUESTION)) The task state segment descriptor for the designated task is

checked for its ----- and --------

((OPTION_A)) Limit and Base

((OPTION_B)) base and address

((OPTION_C)) limit and presence

((OPTION_D)) base and presence

((CORRECT_CHOICE)) (A/B/C/D)

C

((EXPLANATION)) (OPTIONAL)

((MARKS)) (1/2/3...)

1

((QUESTION)) The Task Register(TR) specify the ----- executing task by

pointing to the task State Segment(TSS)

((OPTION_A)) Normal

((OPTION_B)) Currently

((OPTION_C)) ( Multiple

((OPTION_D)) ( Single


B


((MARKS)) (1/2/3...)

2

((QUESTION)) What is the size of visible part present in TR of 80386?

((OPTION_A)) 16 bit

((OPTION_B)) 20 bit

((OPTION_C)) 24 bit

((OPTION_D)) 32 bit

((CORRECT_CHOICE))

A

(A/B/C/D)


((MARKS)) (1/2/3...)

1

((QUESTION)) What is the minimum size of TSS in 80386?

((OPTION_A)) 64 bytes

((OPTION_B)) 104 byte

((OPTION_C)) 4 KB

((OPTION_D)) 64 KB


B


((MARKS)) (1/2/3...)

1

((QUESTION)) Multitasking is activated in ------------mode of the Processor 80386?

((OPTION_A)) Real

((OPTION_B)) Protected

((OPTION_C)) Virtual

((OPTION_D)) V86


A


((MARKS)) (1/2/3...)

1

((QUESTION)) How task switching can be obtained in 80386?

((OPTION_A)) The current task JMPs or CALLs a TSS descriptor

((OPTION_B)) The current task JMPs or CALLs a task gate

((OPTION_C)) An interrupt or exception selects a task gate



D


((MARKS)) (1/2/3...)

1

((QUESTION)) To return from a task, ____ instruction is used.

((OPTION_A)) RET

((OPTION_B)) IRET

((OPTION_C)) JMP

((OPTION_D)) CALL


B


((MARKS)) (1/2/3...)

2

((QUESTION)) Nested task switching is done by ____

((OPTION_A)) using FAR CALL instruction

((OPTION_B)) Exception

((OPTION_C)) fault or trap

((OPTION_D)) all of above


D


((MARKS)) (1/2/3...)

1

((QUESTION)) ............holds task environment

((OPTION_A)) TSS Descriptor

((OPTION_B)) TSS

((OPTION_C)) None of these

((OPTION_D)) TR


B


((MARKS)) (1/2/3...)

1

((QUESTION)) TSS is not accessible to

((OPTION_A)) Program at PL0

((OPTION_B)) User program

((OPTION_C)) Both a & b

((OPTION_D)) None of these


C


((MARKS)) (1/2/3...)

1

((QUESTION)) To support multitasking ...........is used

((OPTION_A)) TSS

((OPTION_B)) TR

((OPTION_C)) Task Gate descriptor

((OPTION_D)) All of these


D


((MARKS)) (1/2/3...)

1

((QUESTION)) For task switching following is used

((OPTION_A)) Interrupts

((OPTION_B)) Exceptions

((OPTION_C)) A & B



C


((MARKS)) (1/2/3...)

1

((QUESTION)) In TSS descriptor if bit B=1 then

((OPTION_A)) Task is busy

((OPTION_B)) Operand is 16-bit

((OPTION_C)) Operand is 32-bit

((OPTION_D)) Operand is byte


A


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2

((QUESTION)) To perform context save 80386 needs minimum storage of


((OPTION_B)) 104 bytes

((OPTION_C)) 128 bytes

((OPTION_D)) 256 bytes


B


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1

((QUESTION)) Size of Task state segment is


((OPTION_B)) 104 bytes

((OPTION_C)) 128 bytes

((OPTION_D)) 256 bytes


B


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1

((QUESTION)) Maximum size of TSS is

((OPTION_A)) 64 KB

((OPTION_B)) 1MB

((OPTION_C)) 4GB

((OPTION_D)) 64 TB


C


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1

((QUESTION)) Task register holds

((OPTION_A)) Base

((OPTION_B)) Limit

((OPTION_C)) Both a & b



D


((MARKS)) 1

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((QUESTION)) ...........points to TSS to specify currently executing task

((OPTION_A)) TR

((OPTION_B)) TP

((OPTION_C)) TSSD



A


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1

((QUESTION)) Which field in TSS holds the 16-bit offset of the beginning of I/O permission bit map

((OPTION_A)) Bit map offset

((OPTION_B)) Back link

((OPTION_C)) CR 3

((OPTION_D)) EIP


A


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2

((QUESTION)) Which of following are dynamic set fields of TSS?

((OPTION_A)) Flag register

((OPTION_B)) Back link

((OPTION_C)) Instruction pointer



D


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1

((QUESTION)) To keep track of previous task 80386 uses

((OPTION_A)) Flags

((OPTION_B)) EIP

((OPTION_C)) Back link



C


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1

((QUESTION)) Which of following are static set fields of TSS?

((OPTION_A)) Selector of LDT

((OPTION_B)) PDBR

((OPTION_C)) T-bit



D


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1

((QUESTION)) Which of following are static set fields of TSS?

((OPTION_A)) I/O map Offset

((OPTION_B)) Pointers to stack

((OPTION_C)) A & B

((OPTION_D)) none of these


C


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2

((QUESTION)) TSS descriptor present in

((OPTION_A)) GDT

((OPTION_B)) LDT

((OPTION_C)) A or B

((OPTION_D)) A



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1

((QUESTION)) Privilege level of stack and code segment must be

((OPTION_A)) Same

((OPTION_B)) Greater than

((OPTION_C)) Less than

((OPTION_D)) Greater or equal


A


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1

((QUESTION)) Which of following are dynamic set fields of TSS?

((OPTION_A)) General purpose register

((OPTION_B)) Segment register

((OPTION_C)) Instruction pointer



D


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1

((QUESTION)) Each isolated task can have

((OPTION_A)) Separate LDT and page directory

((OPTION_B)) Different logical to linear mapping

((OPTION_C)) Different linear to physical mapping



D


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1

((QUESTION)) Each task have following mapping

((OPTION_A)) logical to linear mapping

((OPTION_B)) linear to physical mapping

((OPTION_C)) Sequential

((OPTION_D)) Both A & B


D


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1

((QUESTION)) Each task can have

((OPTION_A)) Separate LDT and page directory

((OPTION_B)) Different logical to linear mapping

((OPTION_C)) Different linear to physical mapping



D


((MARKS)) 2

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((QUESTION)) Bit T in TSS is used for

((OPTION_A)) Enabling task switch trap

((OPTION_B)) disabling task switch trap

((OPTION_C)) Both A & B



C


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2

((QUESTION)) Processor selects task gate descriptor only when the maximum of selectors ............and the ...............of procedure is less than or equal to the ..........of the descriptor

((OPTION_A)) DPL,RPL,CPL

((OPTION_B)) CPL,DPL,RPL

((OPTION_C)) RPL,CPL,DPL

((OPTION_D)) CPL,RPL,DPL


C


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2

((QUESTION)) Processor selects task gate descriptor only when the maximum of selectors RPL and the CPL of procedure are................. to the DPL of the descriptor

((OPTION_A)) less than or equal

((OPTION_B)) Greater than or equal

((OPTION_C)) Same

((OPTION_D)) Less than


A


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2

((QUESTION)) When task gate is used, the DPL of target ..............is not used for privilege checking

((OPTION_A)) TSS descriptor

((OPTION_B)) TR

((OPTION_C)) TSS

((OPTION_D)) Stack


A


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2

((QUESTION)) Which of the following statements are false?

((OPTION_A)) Task switches cannot be recursive

((OPTION_B)) Tasks are not re-entrant

((OPTION_C)) Currently running task is always a busy task



D


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2

((QUESTION)) During task switching without task gate which of the checks are performed

((OPTION_A)) Privilege check

((OPTION_B)) Limit check

((OPTION_C)) Present check



D


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2

((QUESTION)) The DPL of the new TSS descriptor is not used for privilege checking ,when ...........is used for task switch

((OPTION_A)) Task gate

((OPTION_B)) Trap gate

((OPTION_C)) Call gate

((OPTION_D)) Interrupt gate


A

((EXPLANATION

)) (OPTIONAL)

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2

((QUESTION)) In the direct method Task switching is done by

((OPTION_A)) Jumping to task gate

((OPTION_B)) Calling to task gate


((OPTION_D)) Both A or B


C


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2

((QUESTION)) Task switching is done by

((OPTION_A)) Direct method

((OPTION_B)) Indirect method




C


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2

((QUESTION)) During task switching without task gate which of the checks are performed

((OPTION_A)) instruction check

((OPTION_B)) Limit check

((OPTION_C)) Busy task check



B


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2

((QUESTION)) DPL of the task gate is compared with ......... and ..........of the gate selector

((OPTION_A)) CPL,RPL

((OPTION_B)) DPL,RPL

((OPTION_C)) DPL,CPL



A


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1

((QUESTION)) Which bit shows the current task is child task

((OPTION_A)) NT

((OPTION_B)) G

((OPTION_C)) TS

((OPTION_D)) B


A


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2

((QUESTION)) Task switching is done when

((OPTION_A)) A long jump or call instruction contains a selector which refers to a TSS descriptor

((OPTION_B)) Selector in long jump or call instruction refer to a task gate

((OPTION_C)) Interrupt selector refers to a task gate



D


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1

((QUESTION)) 1. What is the long form of TSS in multitasking?

((OPTION_A)) Test Switch Segment

((OPTION_B)) Task switch segment

((OPTION_C)) Task selector segment

((OPTION_D)) Test state segment


B


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2

((QUESTION)) 2. In multitasking where I/O permission bitmap is located?

((OPTION_A)) At the bottom of the Task gate descriptor

((OPTION_B)) At the bottom of the TSS

((OPTION_C)) On the top of the TSS

((OPTION_D)) On the top of Task gate descriptor


C


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2

((QUESTION)) 3. What is the condition necessary to execute I/O privilege

instructions?

((OPTION_A)) (a) CPL <= IOPL

((OPTION_B)) (b) CPL => IOPL

((OPTION_C)) (c) DPL <= IOPL

((OPTION_D)) (d) RPL => IOPL


A


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1

((QUESTION)) What is the size IOPL field?

((OPTION_A)) (a) 1-bit

((OPTION_B)) (b) 2-bit

((OPTION_C)) (c) 8-bit

((OPTION_D)) (d) 4-bit


B


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1

((QUESTION)) The parent task and child tasks are indicated by which fields of the TSS?

((OPTION_A)) (a) Back link field and NT field

((OPTION_B)) (b) NT field and Back link field

((OPTION_C)) (c) ESP and Back link field

((OPTION_D)) (d) NT field and ESP


A


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((QUESTION)) Which instruction is used to nest the tasks?

((OPTION_A)) (a) JMP

((OPTION_B)) (b) CALL

((OPTION_C)) (c) RET

((OPTION_D)) (d)JBE


B


2

((QUESTION)) What condition is needed to permit the current task to switch to the new

task?

((OPTION_A)) (a) Task Gate DPL >= max(CPL, RPL)

((OPTION_B)) (b) Task Gate DPL <= max(CPL, RPL)

((OPTION_C)) (c) Task Gate RPL >= max(CPL, DPL)

((OPTION_D)) (d) Task Gate CPL >= max(DPL, RPL)


A


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1

((QUESTION)) TSS descriptor appears in which descriptor table?

((OPTION_A)) (a) GDT and LDT

((OPTION_B)) (b) GDT

((OPTION_C)) (c) LDT

((OPTION_D)) (d) IDT

((CORRECT_CH B

OICE)) (A/B/C/D)


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1

((QUESTION)) Which portion of the task register is visible?

((OPTION_A)) (a) Selector

((OPTION_B)) (b) Segment descriptor

((OPTION_C)) (c)Selector and base address

((OPTION_D)) (d) Selector and segment limit


A


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2

((QUESTION)) 4. Which portion of the task register is invisible?

((OPTION_A)) (a) Selector

((OPTION_B)) (b) Segment descriptor

((OPTION_C)) (c)Selector and base address

((OPTION_D)) (d) Base address and segment limit


D


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2

((QUESTION)) Which control register is present in task state segment?

((OPTION_A)) CR0

((OPTION_B)) CR1

((OPTION_C)) CR2

((OPTION_D)) CR3


D


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1

((QUESTION)) Which descriptor table base address is present in task state segment?

((OPTION_A)) GDT

((OPTION_B)) IDT

((OPTION_C)) LDT



C


((MARKS)) (1/2/3...)

1

((QUESTION)) What is the meaning of „T‟ field in task state segment?

((OPTION_A)) Trap flag

((OPTION_B)) Task switch trap

((OPTION_C)) Task register

((OPTION_D)) Test register


B


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2

((QUESTION)) . What is the size of segment limit in task state segment descriptor?

((OPTION_A)) (a)8 bit

((OPTION_B)) (b) 16 bit

((OPTION_C)) (c) 20 bit

((OPTION_D)) (d) 32 bit


C


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2

((QUESTION)) . Which instruction is used to load the new TSS selector to the task

register?

((OPTION_A)) STR

((OPTION_B)) STD

((OPTION_C)) CLD

((OPTION_D)) LTR


D


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2

((QUESTION)) Which instruction is used to read the visible portion of the task

register into memory or general-purpose register?

((OPTION_A)) LTR

((OPTION_B)) STR

((OPTION_C)) STD

((OPTION_D)) CLD


B

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1

((QUESTION)) Amongst given which is a privilege instruction?

((OPTION_A)) LOOP

((OPTION_B)) XLAT

((OPTION_C)) TEST

((OPTION_D)) LTR


D

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1

((QUESTION)) What must be the CPL at the time of execution of LTR instruction?

((OPTION_A)) 0

((OPTION_B)) 1

((OPTION_C)) 2

((OPTION_D)) 3


A

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1

((QUESTION)) Which of the following instruction is used in protected mode only?

((OPTION_A)) AAA

((OPTION_B)) LTR

((OPTION_C)) STD

((OPTION_D)) CLD


B

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((QUESTION)) Amongst given which is not a privilege instruction?

((OPTION_A)) STR

((OPTION_B)) HLT

((OPTION_C)) OUT

((OPTION_D)) LTR


C

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1

((QUESTION)) What condition is needed to change the IOPL of any task?

((OPTION_A)) (a) If code is at PL3

((OPTION_B)) (b) If code is at PL2

((OPTION_C)) (c) If code is at PL1

((OPTION_D)) (d) If code is at PL0


D

((MARKS)) (1/2/3...)

1

((QUESTION)) What condition is needed to change the IOPL of any task?

((OPTION_A)) (a) If code is at PL3

((OPTION_B)) (b) If code is at PL2

((OPTION_C)) (c) If code is at PL1

((OPTION_D)) (d) If code is at PL0


D

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1

((QUESTION)) Type field of Busy TSS Descriptor indicates value - -------------






A

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1

((QUESTION)) Type field of Available TSS Descriptor indicates value - -------------






C

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1

((QUESTION)) Type field of task Gate Descriptor indicates value - -------------






A

for a single task in protected mode, the 80386 can address ... · ((marks)) (1/2/3...) 1...

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