DRM Panic QR code generator

原始链接: https://rust-for-linux.com/drm-panic-qr-code-generator

This Rust project generates QR codes to display kernel panic data, addressing the difficulty of copying panic traces from the screen for bug reporting. By encoding the data in a QR code, users can easily scan and paste it into bug reports, streamlining the debugging process. The project prioritizes memory safety, crucial in panic handlers, and uses a self-contained encoder that avoids complex bindings. The author found Rust cleaner and more readable than equivalent C code for this application. Integrated into Linux kernel v6.12-rc1, the project is being enabled in Arch Linux's kernel. A web frontend facilitates decoding (https://github.com/kdj0c/panic_report), and examples are available showcasing the QR code implementation. A standalone Rust application for testing outside the kernel is maintained (https://gitlab.com/kdj0c/qr_panic). The project was primarily developed by Jocelyn Falempe, supported by the Rust for Linux community.

This Hacker News thread discusses a new Linux kernel feature that displays a QR code on kernel panics, allowing users to easily capture and share debugging information. The code is written in Rust, sparking debate. Some users express concerns about "sneaking" Rust into the kernel, fearing it could become mandatory. Others argue Rust is a good choice for memory safety, particularly in panic handlers. Some find the justification for using Rust disingenuous, noting the initial motivation was simply to learn the language. Users also debate the usefulness of a QR code versus traditional debugging information. Some argue QR codes are easier for most people to share in a computer-readable format, leveraging smartphones. Others counter that text is easier to read and share, especially in situations where relying on a decoding device is impractical. The overall sentiment is mixed, with discussions on the trade-offs between language choice and usability.

This is a simple QR code generator, to display the panic data as a QR code. It is specific to the DRM panic use case, and supports only some parts of the QR code specification.

Kernel panic traces are usually displayed on the screen, but then it's hard to copy and paste them to a bug report, so that a developer can take a look, and fix the bug.

As QR code are now widespread, using that allows to easily copy and paste the panic traces in a bug report, which makes debugging much easier for both the user and the kernel developer.

The QR code has a better pixel density than text, that means you can put more debug data into a QR code, than you can see as text only on a standard monitor.

This project was written in rust, because memory safety is critical in a panic handler.

The QR code encoder is self-contained and only uses the provided memory buffer, so there is no need to add complex bindings, and it was easy to merge it in the kernel.

For this particular case, I found the Rust code to be cleaner, and easier to read than the C equivalent, even if I'm much more experienced in C.

The code was merged into Linux kernel version v6.12-rc1. Arch Linux will enable it soon in its kernel.

An example web frontend to decode the panic data from the QR code: https://github.com/kdj0c/panic_report.

A few samples of a panic screen with a QR code are available here: https://github.com/kdj0c/panic_report/issues/1.

You can test the same code in a standalone rust app (outside the kernel): https://gitlab.com/kdj0c/qr_panic.

I try to keep it up-to-date with the latest Linux kernel.

The main author of the QR code generator is Jocelyn Falempe <[email protected]>, with help from the Rust for Linux community.