I usually see options like boot=casper or boot=live. However, I cannot find anything describe the actual meaning of this option and I cannot find any piece of code handle this option at all. From kernel documents it said:
Parameters denoted with BOOT are actually interpreted by the boot loader, and have no meaning to the kernel directly.
So I guess this option is actually handled by whatever bootloader we used. However, I cannot find any code in grub2 or systemd-boot responsible for parsing boot=
. Can anyone point me a direction where should I supposed to find out the code parsing the boot=
option?
updates
hmmm... I think I found it. It is in /init
, which do BOOT=${x#boot=}
and then . /scripts/${BOOT}
. So this actually depends on distro. I guess.