answers-lab5.txt

CSE P 551: Operating Systems (Autumn 2014)
Project 5: Spawn and Shell
Jeff Weiner (jdweiner@cs.washington.edu)
Myles Jordan (mylesj2@cs.washington.edu)
December 5th, 2014 (used one late day)


What we did to solve the exercises:

Jeff did exercises 1-3, Myles did exercises 4-5.  Jeff also helped considerably
with the debugging of ex4, which was broken due to a leftover bug from
assignment 4.  (Thanks for the help with that too, Jialin!)


Challenges completed:

None.


Questions & Answers:

1.  Do you have to do anything else to ensure that this I/O privilege setting
    is saved and restored properly when you subsequently switch from one
    environment to another?  Why?

No, adding the flag to the eflags value in the environment's trapframe will
ensure that whenever the environment is run, the processor runs with that
value (due to it loading that trapframe into the processor, inside env_pop_tf).