UEFI

Build/OvmfX64/DEBUG_GCC5/Ovmf.map

A .map file is basically:

a detailed layout of how the final binary is organized in memory

.map → “where everything is placed” .debug → “what everything means internally”

Debugging with GDB

Get base address

grep PeiCore Build/OvmfX64/DEBUG_GCC5/Ovmf.map

Get debug offset

objdump -h Build/OvmfX64/DEBUG_GCC5/X64/PeiCore.debug

PCI is a bus (communication system) that lets components like network cards, USB controllers, and GPUs talk to the system