ECE 440 · Week 10
Modern Computer: Full Stack
The demo, the repository, and a maintenance note.
Week 10 of 10 · Solitude
ECE 440 · Week 10 · In class
The demo, the repository, and a maintenance note.
- The note says what to redo when the kernel moves, and where spare media is kept.
- The kernel package name is the name of the kernel package the image has installed.
- Copy it from the package list during the lab.
- The shelf is the one on the station sheet.
ECE 440 · Week 10 · In class
The demo, the repository, and a maintenance note. (continued)
- Those two are the homework.
ECE 440 · Week 10 · In class
Have your partner point at one line of the note.
- If they cannot find the spare media from that line, correct the line.
- Stop before a bootloader rebuild.
ECE 440 · Week 10 · Lecture
What a kernel move breaks
- An out-of-tree module is built against one kernel's headers; a new kernel needs a rebuild.
- A device-tree overlay is applied to the new kernel's tree; a renamed node or label breaks it.
- Boot time and power can shift, so the week-5 pair is measured again.
- The note lists what to redo, in order, and how to tell each step worked.
ECE 440 · Week 10 · Lecture
Rebuilding the module for the running kernel
# Makefile
obj-m := mydev.o
KDIR ?= /lib/modules/$(shell uname -r)/build
all:
$(MAKE) -C $(KDIR) M=$(CURDIR) modules
clean:
$(MAKE) -C $(KDIR) M=$(CURDIR) cleanuname -rnames the kernel running now; the headers for it must be installed.- After loading, the bind line from week 4 is the check.
ECE 440 · Week 10 · Lecture
A maintenance note someone else can use
- Written for the next pair, who have the repository and the station sheet and nothing else.
- Each line is an action and a check: "rebuild X, then see Y".
- It names where the spare media is kept, as the station sheet names it.
- It names the kernel package to look up first after a move, copied from the image.
ECE 440 · Week 10 · Lecture
The repository at hand-in
| Item | Why it is there |
|---|---|
| Requirement page | What the product promised |
| Overlay and module source | What runs on the board |
| Unit file | How the service starts, and as whom |
| Measurements and logs | What was shown, with evidence |
| Maintenance note | What to redo when the kernel moves |
ECE 440 · Week 10 · Lecture
The demo
- Show the requirement first, then each claim against it: the driver, the numbers, the service.
- Run things live where you can; show the log where a run takes too long.
- Each partner answers questions alone: know the parts you did not type.
ECE 440 · Week 10 · Lab
Lab
- Demonstrate the project.
- Hand in the repository and a maintenance note. Second pass: have your partner point at one line of the note and correct it if they cannot find the spare media.
- Assemble the lab hand-in: The demo, the repository, and a one-page maintenance note that says what to redo when the kernel moves and where the spare media is kept.
ECE 440 · Week 10 · Lab
Hand in
The demo, the repository, and a one-page maintenance note that says what to redo when the kernel moves and where the spare media is kept.
ECE 440 · Week 10 · Homework
Homework
- Write the kernel package name you would look up first after a kernel move, and the shelf where the spare card sits.
ECE 440 · Week 10 · Homework
Turn in
The package name and the shelf.
ECE 440 · Week 10 · Read
Read
On the lab site: Module 12, A whole system, stops at the system. This week grades the demo, the repository, and the maintenance note.