on my machine TPM is checking state of machine for security reasons, so if this runs ANYWAY then why not use that for one more useful thing ... ( it runs before

on my machine TPM is checking state of machine for security reasons, so if this runs ANYWAY then why not use that for one more useful thing ... ( it runs before even machine thinks about booting anything ) you can define shutdown flag for hardware change: shutdown -rF XD, some things are hot swappable and for that there has to be logic (in kernel) to know you have new hardware... if you have total hardware failure that can be detected too, on next boot...