EFI support in the kernel

[Volker Wysk]

Am Sonntag, den 26.01.2020, 07:58 -0500 schrieb Ken D'Ambrosio:
> On 2020-01-26 07:22, Volker Wysk wrote:
> > Hi
> > 
> > I don't have a /sys/firmware/efi directory. I think this means that
> > the
> > running kernel doesn't have (U)EFI support.
> 
> Note that I'm not a UEFI demigod, but I think you've got it
> backward, 
> really.  UEFI is more about how your system is working than your
> kernel, 
> itself.  By the time you're loading the kernel, everything that
> *needs* 
> to know about UEFI has already done its job: the MBR/bootloader &
> BIOS.  

The problem is, I have a new computer, which runs UEFI. My old one is
BIOS/non-UEFI. Now I have to migrate my system. 

I want to avoid to install and configure everything again, from
scratch, because there are many things which I've installed, which you
can't install easily with apt. Such as my Wiki, my Nextcloud, my
Dovecot mail server...

> (Though, really, UEFI is a replacement for "BIOS", but I'm using the 
> term generically.)  The nutshell is that to get your system booting 
> UEFI, you have to have your BIOS thusly configured, AND do a UEFI-
> based 
> install at installation time.  

That's the second one, which I don't have.

> (The install used to require you to 
> select UEFI from the GRUB menu at install time; I think Ubuntu may
> have 
> enough smarts now to simply pick the default.)  But I don't see
> anything 
> approaching an even vaguely easy way to do this retroactively: you
> need 
> to change your disk layout (need an EFI partition), 

So far I've come.

> need to populate it, 

You mean with grub-install? That's not working, because of the non-
existing kernel support, it seems.

> change your BIOS from "legacy" to "(U)EFI", etc.  I do not see there 
> being anything but pain and suffering trying to make this happen 
> post-facto.

You're so right about the pain and suffering!  %-(

Thank you very much for your guidance. I might have stumbled around for
more time. It now looks like I'll bite the bullet and do it a more
conventional way.


Cheers
Volker