Modern days Linux kernel requires a bootloader, as seen in the video. In the old days, you could dd the kernel to the floppy disk and use rdev to point to the root partition to start after loading the kernel.
The code is so tiny they could have kept it... But, oh well, progress.
I like the message:
- .ascii "Loading"
+bugger_off_msg:
+ .ascii "Direct booting from floppy is no longer supported.\r\n"
+ .ascii "Please use a boot loader program instead.\r\n"
+ .ascii "\n"
+ .ascii "Remove disk and press any key to reboot . . .\r\n"
+ .byte 0Not for long; the EFI headers later used the same space, which even required severely shortening that "no longer supported" message (the first two lines of the message were replaced by just "Use a boot loader.\r\n")