Singularity: Reading Question

Ren, a rogue SIP, has managed to break the memory independence invariant by obtaining a pointer to an object in another SIP, named Luke. Thankfully, Ren isn’t entirely evil: it will only read from, never write to, the pointer that it’s obtained.

Keeping Singularity’s design in mind, for each of the following, describe a scenario that can lead to the incident.

  1. Ren crashes as a result of dereferencing the rogue pointer.

  2. Luke crashes as a result of dereferencing the rogue pointer.

  3. The entire operating system crashes.


Local Stanford students should write up their response on a sheet of paper that includes their name and SUNetID. The sheet of paper with the response should be submitted immediately before lecture.

SCPD students should write up their response in a text file named response.sing.txt and upload it via the submission and grades page. You'll need to sign in with your SUNetID to access the page. Responses will be accepted until one week after the corresponding paper's lecture.

In either case, the response should be short, likely only a pithy paragraph in length.


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