The kernel starts everything else by unpacking an archive containing a minimal environment to set stuff up for later. Such as loading needed kernel modules, decrypting your drive, etc. It then launches, by default, the /init program (mines a shell script).
That program is PID 1. If it dies, your kernel will panic.
After it finishes setup, it execs your actual /sbin/init. These means it dies, and that program (systemd, openrc, dinit, runit, etc) becomes PID 1. If an issue happens, both could fail to execute and the kernel will loop forever.
Uhm, zero? With ten years of using Linux? What did you do to fuck up the damn kernel? o_O
It can be done if you mess with the initramfs.
The kernel starts everything else by unpacking an archive containing a minimal environment to set stuff up for later. Such as loading needed kernel modules, decrypting your drive, etc. It then launches, by default, the /init program (mines a shell script).
That program is PID 1. If it dies, your kernel will panic.
After it finishes setup, it execs your actual /sbin/init. These means it dies, and that program (systemd, openrc, dinit, runit, etc) becomes PID 1. If an issue happens, both could fail to execute and the kernel will loop forever.