ECE 441 · Week 2
Modern Computer: Secure Infrastructure
Each boot stage needs one log line and one public paragraph.
Week 2 of 10 · Solitude
ECE 441 · Week 2 · In class
Each boot stage needs one log line and one public paragraph.
- The pair is a citation, not a stage map.
- The log line is from a capture on this board.
- The paragraph is from a public document, with that document's title and section number.
- Write the title and the section number before you copy the paragraph.
ECE 441 · Week 2 · In class
Each boot stage needs one log line and one public paragraph. (continued)
- That pair is the homework.
ECE 441 · Week 2 · In class
On the second pass, swap one paragraph for a nearer section, then keep the one you will cite.
- A stage map with no public paragraph is an earlier course's hand-in.
- This week collects the citation.
ECE 441 · Week 2 · Lecture
Where the boot log comes out
- Console TX
- Console RX
- Console ground
Other pins are dimmed. Colours as on the Solitude pinout, where each pin's name is. The square pad is pin 1.
ECE 441 · Week 2 · Lecture
A citation, not a stage map
- A stage map says what runs in what order; that was an earlier course's hand-in.
- A citation ties one stage to two things: a line this board printed, and a public paragraph about that stage.
- Either half alone is a claim; the pair is evidence.
ECE 441 · Week 2 · Lecture
Capture the whole boot, from power-on
# lab PC: stamp every console line, keep it all
picocom -b 115200 /dev/ttyUSB0 | ts '%.s' | tee boot.log- Start the capture, then apply power, so the earliest stage's lines are kept.
- The kernel's own log starts late:
dmesgnever sees the stages before it. - Keep the raw file; cite lines from it, not from memory.
ECE 441 · Week 2 · Lecture
Which lines belong to which stage
- Early stages print short, terse lines, often before the console is fully set up.
- U-Boot prints a banner with its version and build date.
- The kernel starts with
Booting Linux on physical CPUand its version line. - The init system prints its own banner once userspace starts.
ECE 441 · Week 2 · Lecture
Citing the paragraph
| Stage | Log line | Document title | Section | Paragraph |
|---|---|---|---|---|
| … | copied verbatim | full title | number | quoted |
- Write the title and section number before copying: a quote with no source cannot be checked.
- Prefer the nearest section, the one about this stage, over a general overview.
ECE 441 · Week 2 · Lab
Lab
- For each boot stage, cite one line from a log and one paragraph from a public document.
- Second pass: swap one paragraph for a nearer section, then keep the one you will cite.
- Assemble the lab hand-in: A citation table: each boot stage, one log line, and one public paragraph.
ECE 441 · Week 2 · Lab
Hand in
A citation table: each boot stage, one log line, and one public paragraph.
ECE 441 · Week 2 · Homework
Homework
- Pick one stage and write the public document's title and section number you will cite, before you copy a paragraph.
ECE 441 · Week 2 · Homework
Turn in
The document title and the section number.
ECE 441 · Week 2 · Read
Read
On the lab site: Module 3, The boot ROM, through Module 8, Linux boots, name the stages. This week grades the citation table. Past Module 12, the citations are the method.
ECE 441 · Week 2 · Next
Week 3
How to diff the live device tree against the source tree.