boredsquirrel , 5 hours ago

You can use measured boot as part of the firmware boot process, store a hash of the known good boot files on a trusted media and compare that.

This is done with the Heads payload in Coreboot. But support is like only Thinkpads and now also soon Novacustom, Nitrokey and maybe System76 laptops.

The thing is, then you know your kernel is safe, but what about the rest? Depending on the attack vector, a system like on Android with full immutability and a recovery that verified the whole OS root partition would be safer.

But this means that you have no ability to customize, without breaking things.