LinuxBoot: Linux as Firmware

Well, it depends on your definition of "whole Linux". By it's nature, it can be stripped down fairly lean, especially if you know precisely which drivers you need, and don't need a lot of user-space support libraries, etc.

It is possible for *nix to be very minimal, less so than in the old days, of course. But speaking of the old days, when I earned my bread as a CPU logic designer, I recall one grizzled OS developer's reaction to the looooong errata list for the A0 stepping of some new silicon: "Pffft. I can bring up Unix on a broken washing machine."

Don't forget OpenSSL. Imagine how long SSLv3 or export ciphers would last if this was done in the 1990s

IMO, the problems that [U]EFI introduces (that far exceed the historical limitations it overcomes) should be self-evident.

IMO, he should not have to argue against having multiple, redundant copies of drivers, shells and utilties each accessible only in its own "OS" (UEFI, GRUB, OS). It should not be a debate. This is definitely not "defense in depth". IMO, whomever controls the first OS controls the computer because there is no need for the second and third OS in order to do work (make network connections, move files across the network, etc.).

These "hardware features", whether its [U]EFI or ME or whatever acronym, IMO is a land grab by hardware vendors over what we know as the "OS". Less computer owner control, more vendor control. The sum effect of all these "features" is that verification that something is the way that the owner wants it and has not been modified is far too complex and is ultimately under control of the vendor, not the computer owner.

I do most work on the commandline in text-mode (no graphics layer) and as such I only need one OS, with some basic utilities. When the news came that new computers would have [U]EFI, I considered whether I should just switch from the OS I am using to [U]EFI. It seemed to have all the utilities I would need to do work, along with the ability to extend with new programs.

I only need one OS to boot to a working environment. I should be able to choose that OS. I hope that Minnich and Hudson and others will consider that the user may want to choose a kernel other than Linux as a source for drivers, e.g., BSD, Plan9, others incl. future OS not yet written, etc., even if it today it has inferior driver support compared to Linux, or Intels UEFI, or whatever.

The speaker seemed a bit perplexed when someone in the audience questioned whether Linux is a "TCB". What is and what is not a "TCB" should be the computer owners decision, and not anyone elses. If the computer owner wants to cede authority for that decision to a third party, then she can make that choice. But IMO it should be a choice made by the computer owner, and not anyone else.

This is in the hands of the firmware/hardware manufacturers. AFAIK, for instance, the version of Minix that serves as Intel's ME will continue to be operational even if the UEFI is replaced by Linux.

The issue is that 'firmware' actually means many different blobs of software in various ROMs spread throughout the system, from disk controllers to GPUs to memory controllers to NIC and so on.

You will never be able to verify you have full control over your system unless all these firmware have the ability to be reflashed/replaced. LinuxBoot/Coreboot are a step in the direction, but without major concessions from hardware vendors this is an uphill battle.

We should clarify that. Our example is an OCP Winterfell node, where boot time went from 8 minutes to 20 seconds.