memory-debugging

What problem does it solve?

Memory-related bugs like page faults, double faults, and heap corruption are among the most challenging and critical issues in kernel development. This Skill provides a systematic approach to diagnose and resolve these complex memory problems, ensuring kernel stability and preventing system crashes.

Core Features & Use Cases

• Page Fault Analysis: Decode error codes and identify causes like unmapped memory or protection violations.
• Double Fault Diagnosis: Pinpoint the root cause of cascading exceptions, often related to stack or page table issues.
• Allocator Debugging: Troubleshoot frame, heap, and kernel stack allocation failures and leaks.
• Use Case: Your kernel is experiencing a PAGE FAULT during a system call. Use this Skill to decode the error code, determine if it's a read/write access or a user/kernel mode issue, and systematically investigate the page table mappings and kernel stack configuration to find and fix the underlying memory bug.

Quick Start

Decode a Page Fault error code (e.g., 0x4)

Bit 0 (P): 0 = Page not present

Bit 1 (W): 0 = Read access

Bit 2 (U): 1 = User mode

Diagnosis: Read from unmapped page in user mode

Add checkpoint logging to narrow down

log::debug!("CHECKPOINT: Before page table operation"); page_table.map_to(page, frame, flags, allocator)?; log::debug!("CHECKPOINT: After page table operation");