A detailed walkthrough of the Linux boot process from the moment you press the power button to the kernel's first C function. Covers CPU real mode and the reset vector, BIOS vs UEFI firmware, GRUB bootloader operation, the setup program's workspace initialization, the step-by-step transition from real mode to 32-bit protected mode and then to 64-bit long mode, kernel decompression via extract_kernel, ELF loading and relocations, and kASLR randomization. Includes a glossary of low-level terms like GDT, IDT, paging, page tables, control registers, and EFER.
Table of contents
Part 1 — From power button to the kernel’s first breathPart 2 — Leaving real mode, stepping through 32‑bit land, and arriving in 64‑bitPart 3 — Unpacking the real kernel, fixing addresses, and why Linux sometimes moves itselfA quick glossary you can bookmark3 Impressions