Play with esp32 to create domotics stuff by aginies

Description

Play with ESP32 board and multiple small peripherals

https://github.com/aginies/domotique

Goals

• Finish the pool project
• add support of NFC auth in the door project
• improve the doc
• project to manage solar panel (router)

Resources

esp32 home

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early stage kdump support by mbrugger

Project Description

When we experience a early boot crash, we are not able to analyze the kernel dump, as user-space wasn't able to load the crash system. The idea is to make the crash system compiled into the host kernel (think of initramfs) so that we can create a kernel dump really early in the boot process.

Goal for the Hackweeks

1. Investigate if this is possible and the implications it would have (done in HW21)
2. Hack up a PoC (done in HW22 and HW23)
3. Prepare RFC series (giving it's only one week, we are entering wishful thinking territory here).

update HW23

• I was able to include the crash kernel into the kernel Image.
• I'll need to find a way to load that from init/main.c:start_kernel() probably after kcsan_init()
• I workaround for a smoke test was to hack kexec_file_load() systemcall which has two problems:
  1. My initramfs in the porduction kernel does not have a new enough kexec version, that's not a blocker but where the week ended
  2. As the crash kernel is part of init.data it will be already stale once I can call kexec_file_load() from user-space.

The solution is probably to rewrite the POC so that the invocation can be done from init.text (that's my theory) but I'm not sure if I can reuse the kexec infrastructure in the kernel from there, which I rely on heavily.

update HW24

• Day1
  • rebased on v6.12 with no problems others then me breaking the config
  • setting up a new compilation and qemu/virtme env
  • getting desperate as nothing works that used to work
• Day 2
  • getting to call the invocation of loading the early kernel from __init after kcsan_init()

• Day 3

  • fix problem of memdup not being able to alloc so much memory... use 64K page sizes for now
  • code refactoring
  • I'm now able to load the crash kernel
  • When using virtme I can boot into the crash kernel, also it doesn't boot completely (major milestone!), crash in elfcorehdr_read_notes()

• Day 4

  • crash systems crashes (no pun intended) in copy_old_mempage() link; will need to understand elfcorehdr...
  • call path vmcore_init() -> parse_crash_elf_headers() -> elfcorehdr_read() -> read_from_oldmem() -> copy_oldmem_page() -> copy_to_iter()

• Day 5

  • hacking arch/arm64/kernel/crash_dump.c:copy_old_mempage() to see if crash system really starts. It does.
  • fun fact: retested with more reserved memory and with UEFI FW, host kernel crashes in init but directly starts the crash kernel, so it works (somehow) \o/

• TODOs

  • fix elfcorehdr so that we actually can make use of all this...
  • test where in the boot __init() chain we can/should call kexec_early_dump()

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pudc - A PID 1 process that barks to the internet by mssola

Description

As a fun exercise in order to dig deeper into the Linux kernel, its interfaces, the RISC-V architecture, and all the dragons in between; I'm building a blog site cooked like this:

• The backend is written in a mixture of C and RISC-V assembly.
• The backend is actually PID1 (for real, not within a container).
• We poll and parse incoming HTTP requests ourselves.
• The frontend is a mere HTML page with htmx.

The project is meant to be Linux-specific, so I'm going to use io_uring, pidfs, namespaces, and Linux-specific features in order to drive all of this.

I'm open for suggestions and so on, but this is meant to be a solo project, as this is more of a learning exercise for me than anything else.

Goals

• Have a better understanding of different Linux features from user space down to the kernel internals.
• Most importantly: have fun.

Resources

• https://github.com/mssola/pudc

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Backfire TV - Take back control of your Firestick by andreabenini

Take Back Control of Your Amazon Firestick.
Tired of Ads, a cluttered launcher, and buttons you can't change? BackFireTV is a project to liberate your Firestick from Amazon's walled garden and make it truly yours. They call it the firestick. To fight fire with fire, you need a backfire.

That's the soul of BackFireTV. To truly liberate it and return back to its core capabilities this project uses a linux script, one Android app and ADB access against Amazon's restrictive policies. We leverage these internal tools to create a "backfire" against the incessant ads and locked ecosystem, transforming your Firestick back into the useful, customizable device it was always meant to be.

Goals

I'm still defining it as a side project and something I'll surely do in the upcoming days with hw I already have. btw I'd like to register it in advance in order to work on it. I already have a somehow working concept I'll redefine later during the week

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Capyboard, ESP32 Development Board for Education by emiler

Capyboard is an ESP32 development board built to accept individual custom-made modules. The board is created primarily for use in education, where you want to focus on embedded programming instead of spending time with connecting cables and parts on a breadboard, as you would with Arduino and other such devices. The board is not limited only to education and it can be used to build, for instance, a very powerful internal meteo-station and so on.

• github.com/realcharmer/capyboard
• github.com/realcharmer/capyboard-starter
• github.com/realcharmer/capyboard-docs
• github.com/realcharmer/capyboard-examples
• docs.capyboard.dev

Hack Week 25

My plan is to create a new revision of the board with updated dimensions and possibly even use a new ESP32 with Zigbee/Thread support. I also want to create an extensive library of example projects and expand the documentation. It would be nice to also design additional modules, such multiplexer or an environment module.

Goals

• Implement changes to a new board revision
• Design additional modules
• Expand documentation and examples
• Migrate documentation backend from MkDocs to Zensical

Hack Week 24

I created a new motherboard revision after testing my previous prototype, as well as a light module. This project was also a part of my master's thesis, which was defended successfully.

Goals

• Finish testing of a new prototype
• Publish source files
• Documentation completion
• Finish writing thesis

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