On Sun, Sep 9, 2018 at 6:32 AM, Tom Horsley <horsley1953(a)gmail.com> wrote:
On Sat, 8 Sep 2018 20:43:46 -0600
Chris Murphy wrote:
> Nope. There's no firmware state information saved to disk.
There must be something on disk, because I keep
reading web pages that say things like:
You can create a new image file and add it to the
efi menu with efibootmgr (without, of course,
ever having an example :-).
Example from an old anaconda/program.log
15:12:07,059 INFO program: Running... efibootmgr -c -w -L Fedora -d
/dev/md/Volume0_0 -p 1 -l \EFI\fedora\shim.efi
That gets translated by efibootmgr/efivars into an NVRAM boot entry.
But this is for making it persistent. It has nothing to do with
sticks. Sticks should have their bootloader in EFI/BOOT/BOOT<arch>.EFI
where <arch> is X64 on x86_64 systems, and IA32 for 32-bit UEFI
systems, and so on. The firmware has rules for the order it looks for
a valid OS Loader, that are in the UEFI spec. But the gist is that if
you plug in a stick you have to tell the firmware you want to boot off
the stick, and the way you do that is choosing that stick from a menu.
And then it knows to look in EFI/BOOT and then what arch EFI file it
should read and execute.
--
Chris Murphy