Prelude In this post I will attempt to explain interrupt handling and stack switching in x86-64 architecture. I decided to write this because I couldn’t understand the interrupt procedure call or how stack switches work in a lab from Xeno’s Architecture 2001: x86-64 OS Internals course at OpenSecurityTraining2. Therefore, with the help of Xeno’s slides and the Intel manual, I have tried to simplify and explain these topics here. For anyone curious about the lab that started it all, I have also put together a writeup here.