How Linux Init Switches from Kernel to User Mode: Inside kernel_execve

This article explains how the Linux init process (pid 1) transitions from kernel mode to user mode using kernel_execve and the int 0x80 system call, detailing the register changes, assembly flow, and verification experiment that reveal the privilege level switch.

System Callinit processkernel_execve

0 likes · 10 min read

How Linux Init Switches from Kernel to User Mode: Inside kernel_execve

ITPUB

Jun 22, 2017 · Fundamentals

How Does Linux’s Init Process Switch from Kernel to User Mode?

This article explains how the Linux init process (pid 1) transitions from kernel mode to user mode, detailing the role of kernel_thread, run_init_process, kernel_execve, the int 0x80 system call, register changes, and a practical experiment confirming the __USER_CS value.

AssemblySystem Callinit process

0 likes · 13 min read

How Does Linux’s Init Process Switch from Kernel to User Mode?