1 votes 1 votes Shouldn’t the answer be A but D is provided as an answer Operating System gateforum-test-series operating-system io-handling + – Gupta731 asked Nov 25, 2018 edited Mar 15, 2019 by ajaysoni1924 Gupta731 665 views answer comment Share Follow See all 7 Comments See all 7 7 Comments reply Shaik Masthan commented Nov 25, 2018 reply Follow Share Type the questions instead of screenshots By the way, D is the correct answer 1 votes 1 votes Shaijal Tripathi commented Nov 25, 2018 reply Follow Share @ Shaik Masthan, kindly elaborate the reason why you choose D. Also, can memory access be counted as a hardware operation? As when restriction occurs on memory usage, the interrupt is provided by OS only. 0 votes 0 votes kumar.dilip commented Nov 25, 2018 reply Follow Share Anything from the operating system is called kernel mode otherwise user mode. So, option D seems to be correct. 0 votes 0 votes gauravkc commented Nov 25, 2018 reply Follow Share You have programs to execute on the machine. Hardware form the set of resources using which the programs will execute. If processes are not carefully monitored, they might create unfavorable outcomes/situations for us. To control this, we have two modes for execution User mode - to let processes have their fair share of hardware for execution Kernel mode - to manage them properly to avoid chaos 1 votes 1 votes goxul commented Nov 25, 2018 reply Follow Share A is also correct - there are two modes, namely user and kernel, so that the user space processes can't access memory locations which are not meant for it. 0 votes 0 votes gauravkc commented Nov 25, 2018 reply Follow Share They are asking for the reason. Restricting memory access was not the reason why 2 modes of execution was implemented. Managing access to hardware is. Hence, D is more appropriate. Though technically A is not incorrect. 0 votes 0 votes Arjun commented Nov 25, 2018 reply Follow Share Memory protection is given by "Virtual Memory" using access bits in the Page/Segmentation table. There is no need of mode switching here - even Kernel is another process. 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes Yes answer will be D. To handle the priveleged instructions we need the two modes...memory protection is generally given by virtual memory as said by Arjun sir Psy Duck answered Mar 3, 2023 Psy Duck comment Share Follow See all 0 reply Please log in or register to add a comment.