cs4022_2026T1_Q1_NA.pdf

If the memory map for a device starts from the offset 0x40002000 and has a size of 4096 bytes in a 32-bit addressing scheme, what will be the last address in the memory map?

Consider the following memory-mapped register code: [[IMAGE:dc5f4d3811137c61_3_2]] What are the access sizes of the [[IMAGE:dc5f4d3811137c61_4_3]] and [[IMAGE:dc5f4d3811137c61_4_4]] registers, respectively?

What will be the output behavior of the following xv6 code snippet? [[IMAGE:dc5f4d3811137c61_4_9]]

Which of the following correctly describes the sequence of steps when a new process is forked in xv6? (i) Allocate a new proc structure. (ii) Copy the parent’s memory space to the child. (iii) Set up the trapframe for the child process. (iv) Add the child to the ready queue.

Consider image of the page table entry is given below and the code for kvminit in vm.c. [[IMAGE:dc5f4d3811137c61_5_12]] [[IMAGE:dc5f4d3811137c61_6_13]] What will be the values of the first 5 bits (from the right) of the page table entry after the execution of [[IMAGE:dc5f4d3811137c61_6_14]] ?

Consider the following code snippet for the syscall function in kernel/syscall.c (RISC-V xv6): [[IMAGE:dc5f4d3811137c61_7_15]] Why does xv6 store the system call number in the [[IMAGE:dc5f4d3811137c61_7_16]] register before invoking the kernel?

When a user types the command [[IMAGE:dc5f4d3811137c61_7_17]] in a Linux shell, which of the following sequences of system calls is most likely to occur for executing the command and then returning control to the shell?

A system has a virtual memory space of 8 GB and uses a single-level page table with 2\(^{21}\) entries. What is the size of each page frame?

Consider a system with 128 MB of physical memory and a 32-bit virtual address space. Given a page size of 8 KB, what will be the maximum number of page frames that can be present in RAM?

What could be the possible output of the following program? [[IMAGE:dc5f4d3811137c61_9_18]]

In RISC-V, during system calls, which register stores the current program counter?

Consider the given memory map. [[IMAGE:dc5f4d3811137c61_10_19]] The memory address 0x200003CD corresponds to ________

State True or False: In xv6, after a user process calls fork(), both the parent and child processes have separate copies of the trapframe, so changes in one do not affect the other.

In xv6, a running process can be preempted by the scheduler due to a timer interrupt. What is the resulting state transition of the process?

When a process invokes the exec system call, which components in the Process Control Block (PCB) remain unchanged?

Consider a process A that forks B, B forks C, and C forks D. Processes A and B keep running, but process C terminates before D finishes. Later, D also terminates. Which process is responsible for waiting for and reaping process D?

Select the functions present in kernel/trampoline.S, and are responsible for switching from kernel pagetable to process pagetable and vice versa.

Consider the following processes in an xv6-like operating system: • Process P1 is ready to run and waiting in the run queue. • Process P2 is currently executing on the CPU. • Process P3 has called [[IMAGE:dc5f4d3811137c61_12_20]] waiting for an I/O event. • Process P4 has exited but its parent has not yet called [[IMAGE:dc5f4d3811137c61_12_21]] . Select all the correct statements about the states of the processes.