efivars

[FMDF]

On Thu, 23 Sep 2021, 11:57 Ruben Safir, <ruben at mrbrklyn.com> wrote:

>
> Why does it need the bootloader to do any of that.


You still don't want to listen: the OS does not need to use bootloaders to
do the things that Greg and I listed.

It needs UEFI runtime services; please don't be lazy and read Wikipedia
article whose I provided the link.

This is copy-pasted for your convenience:

"The Unified Extensible Firmware Interface (UEFI)[1]
<https://en.m.wikipedia.org/wiki/Unified_Extensible_Firmware_Interface#cite_note-1>
is
a publicly available specification
<https://en.m.wikipedia.org/wiki/Specification> that defines a software
interface <https://en.m.wikipedia.org/wiki/Interface_%28computer_science%29>
between
an operating system <https://en.m.wikipedia.org/wiki/Operating_system> and
platform firmware <https://en.m.wikipedia.org/wiki/Firmware>. UEFI replaces
the legacy Basic Input/Output System (BIOS
<https://en.m.wikipedia.org/wiki/BIOS>) firmware interface originally
present in all IBM PC-compatible
<https://en.m.wikipedia.org/wiki/IBM_PC_compatible> personal computers
<https://en.m.wikipedia.org/wiki/Personal_computer>,[2]
<https://en.m.wikipedia.org/wiki/Unified_Extensible_Firmware_Interface#cite_note-Intel2000-2>
[3]
<https://en.m.wikipedia.org/wiki/Unified_Extensible_Firmware_Interface#cite_note-ElReg1-3>
with
most UEFI firmware implementations providing support for legacy BIOS
services[]".

If you spend few minutes there, you'll find also information there about
the two different logical roles of UEFI:

"EFI defines two types of services: boot services and runtime services.
Boot services are available only while the firmware owns the platform
(i.e., before the ExitBootServices() call), and they include text and
graphical consoles on various devices, and bus, block and file services.
Runtime services are still accessible while the operating system is
running; they include services such as date, time and NVRAM
<https://en.m.wikipedia.org/wiki/Non-volatile_random-access_memory>
 access.".

Boot services are available only while the firmware owns the platform, so
please stop saying "Why does it need the bootloader to do any of that[?]"

I told you that Linux can be booted without bootloaders, but that it still
needs the UEFI runtime services. I also provided a link to the Kernel
official  documentation to prove it.

Anyway, it really looks like you don't care to listen and that your main
interest is standing by your own (unsubstantiated) positions.

Thanks,

Fabio


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