The u-boot USB stack is not as fault tolerant as Linux. Any failure that occur when scanning and enumerating USB devices has the potential to cause unhandled hard faults that will result in the system rebooting.
There are a lot of problematic USB devices out there and this can cause boot loops which is unwanted behavior. To avoid the boot loops, you can disable USB scanning at startup if your OS is not on USB storage.
- Create file called
boot.inion your first partition (usually mounted at /boot/efi).
preboot=to the file on a new line.