This is not the current version of the class.

Lecture 5

This lecture had some lecture material (notes by Alisha Ukani) and some questions we worked through in groups.

Notes

Pset 2 preview

Entry points (pset 1)

Context switches

Yield mechanisms

The timer interrupt case (INT_IRQ + INT_TIMER in kernel.cc) calls proc::yield_noreturn(). Change it to call proc::yield() instead.

The SYSCALL_YIELD case (in kernel.cc) calls proc::yield(). Change it to call proc::yield_noreturn() instead.

System calls and information leaks

The syscall_entry implementation can leak information from the kernel. Explain how, and explain whether and why this is a problem. Find a good reference online to a similar issue in Linux or another kernel.