[Initramfs] Topic: Initramfs Demystified: Owning Early Userspace in Embedded Linux

Here's the proposal I would like to present under Kernel Summit 
Presentations for LPC, Europe 2026.


Abstract:
When an embedded Linux system fails to boot, initramfs quickly turns 
from a build artifact into a blocker. Most developers rely on it, few 
truly understand it.

This talk turns initramfs from a black box into a tool you can reason 
about and control. We start by unpacking the cpio archive the kernel 
expands into tmpfs and trace the exact path to /init. From there, we 
focus on practical early-userspace design: writing /init from scratch, 
handling device discovery without udev (devtmpfs, mdev, static nodes), 
and deciding what belongs in the kernel versus initramfs. We also 
dissect switch_root vs pivot_root—and the subtle failures that arise 
when they’re misused.

Finally, we cover ARM-specific workflows, including embedding initramfs 
into U-Boot FIT images and handling hardware initialization before the 
real rootfs is available.

Attendees will leave with a clear, portable mental model and the 
confidence to debug and design early boot across Yocto, Buildroot, and 
custom systems

Regards,
Moteen