Kali 2021.1 boot from USB on RPi4 8GB model

[roadrunner64]

Problem: Kali 2021.1 wont boot from USB on RPi4 8GB model, memory card works fine.

I have modified /etc/fstab and /boot/cmdline.txt to point to sda instead of memory card, i have even copied .dat and .elf files from raspberry github repo (https://github.com/raspberrypi/firmware/tree/master/boot) to /boot/, but no luck booting. After coping boot files from github, i got it to start loading kernel but it hangs before mounting root. Without new boot files, it does not start boot sequence. RaspberryOS boots from USB just fine.

Also updated RPi eeprom using RaspberryOS.

Has anyone 8GB model booting Kali from USB to work?

[rcfa]

This works, but it's a tiny bit tricky.

Basically: first install Raspian on a card, update to the latest USB-boot-capable firmware
Then you have to image your kali card onto the USB drive
Then mount that drive on another system and modify the /boot/cmdline.txt and /etc/fstab accordingly.
At some point, it was necessary to "steap" some of the files in /boot from the Raspian image, too. Not sure if that's still necessary.

I wanted to post a how-to a while ago, but I keep having trouble logging into these forums here, so it's hit or miss if I get access, not sure why.

If I find some time, I'll post in more detail, but maybe that's enough to get you going for now.