Introduce coredump server

[etiaro]

JIRA: RTOS-1054

Description

Introduces a coredump_server application running in user space responsible for printing and saving coredumps of any crashing processes, allowing for post-mortem analysis with GDB.
Communicates with kernel on predefined port, similarly to klog, using message structures defined in kernel includes.
Utilizes new device /dev/coredumpctrl for runtime configuration by running coredump_server program with configuration options.

Motivation and Context

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (refactoring, style fixes, git/CI config, submodule management, no code logic changes)

How Has This Been Tested?

• Already covered by automatic testing.
• New test added: (add PR link here).
• Tested by hand on: ia32-generic-qemu, armv7r5f-zynqmp-qemu, sparcv8leon-generic-qemu

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing linter checks and tests passed.
• My changes generate no new compilation warnings for any of the targets.

Special treatment

• This PR needs additional PRs to work (list the PRs, preferably in merge-order).
• coredump: coredump server support phoenix-rtos-kernel#682
• I will merge this PR by myself when appropriate.

[gemini-code-assist]

Summary of Changes

Hello @etiaro, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a new coredump server that automatically captures the state of a crashed process. It generates standard ELF coredump files, which are essential for debugging and understanding system failures. The server is designed with a modular architecture, including a Hardware Abstraction Layer (HAL) for cross-platform compatibility and a flexible settings mechanism to control the scope and output of the coredumps. This enhancement significantly improves the system's diagnostic capabilities by providing detailed crash information.

Highlights

• New Coredump Server: This pull request introduces a new coredump_server component, designed to capture the state of a crashed process. This server will generate standard ELF-formatted coredump files, providing a comprehensive snapshot for post-mortem debugging.
• Broad Architecture Support: The server is integrated into the build system across numerous target architectures (e.g., AArch64, ARMv7, IA32, RISC-V, SPARCv8LEON) by adding it to their DEFAULT_COMPONENTS in respective Makefiles. This ensures broad platform support for crash analysis.
• Configurable Coredump Generation: The coredump server is highly configurable, allowing users to specify parameters such as the maximum number of threads to dump, the memory scope (e.g., only exception thread stack, all stacks, or all memory), whether to include floating-point context, and the maximum chunk size for memory dumps. It also supports saving coredumps to a specified file path or printing them to the console.
• Architecture-Specific Context Capture (HAL): A new Hardware Abstraction Layer (HAL) has been implemented to handle architecture-specific details of capturing CPU registers, FPU contexts, and other process-related auxiliary notes, ensuring accurate and consistent coredump generation across diverse hardware.
• Efficient Data Encoding and Integrity: The coredump data is encoded using Base64 and Run-Length Encoding (RLE), and includes a CRC32 checksum for data integrity. This ensures efficient and reliable transfer and storage of the coredump information.

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[gemini-code-assist]

Code Review

This pull request introduces a coredump server, a significant new feature. The implementation is extensive, with support for multiple architectures, and the code is generally well-structured. I have identified a few critical and high-severity issues related to resource management, robustness, and correctness that should be addressed before merging. Specifically, there's a critical bug in main() where a port is destroyed before it's created, and a few cases where the server could crash or exhibit undefined behavior due to improper error handling or resource management. I've also included several medium-severity suggestions to improve maintainability, portability, and code clarity. Overall, this is a solid foundation for the coredump functionality.