Reinstalling the bootloader

[Andrew Lutomirski]

On Mon, Apr 14, 2014 at 2:55 PM, Chris Murphy <lists at colorremedies.com> wrote:
>
> On Apr 9, 2014, at 12:59 PM, Andrew Lutomirski <luto at mit.edu> wrote:
>
>> On Tue, Apr 8, 2014 at 7:41 PM, Chris Murphy <lists at colorremedies.com> wrote:
>>>
>>> You need to install or reinstall grub2-efi and shim packages.
>>
>> Aha, a correct answer!  Thanks!  Based on this hint, I think I figured
>> it out.  I updated the
>> wiki accordingly.
>>
>> Can you take a quick look at:
>> https://fedoraproject.org/wiki/GRUB_2#Updating_GRUB_2_configuration_on_UEFI_systems
>
> Create a boot menu entry can be skipped if it's not a dual boot system. /boot/efi/EFI/BOOT contains shim.efi as bootx64.efi which is run by default on a system without an NVRAM entry already pointing to shim or grub, and a fallback entry is created automagically. With Windows, yeah you probably have to do something manually because it probably always boots Windows otherwise.
>

Not on my crappy motherboard :(  It apparently can't boot from
EFI/BOOT on a hard disk.  Sigh.

I tried to clarify it a bit, though.

>
>
>>>> It's currently mostly working, modulo the efibootbgr issue.  But I
>>>> don't actually know what to type into efibootmgr to fix it, the OOPS
>>>> notwithstanding.  I can probably figure it out once the OOPS is fixed.
>>>
>>> Strictly speaking you don't need to point  UEFI non-Secure Boot computer to shim.efi, you can just leave it alone and put a grub.cfg in the proper place. At the grub prompt if you type set you should see either config_directory= and prefix= to show where it's looking for the grub.cfg.
>>
>> https://bugzilla.kernel.org/show_bug.cgi?id=73761
>> https://bugzilla.redhat.com/show_bug.cgi?id=1085957
>
> I'm not familiar with this usage: efibootmgr -B -b 0
>
> If 0 is the same as 0000 then that seems to ask for the removal of a fixed entry: the DVD in CSM-BIOS mode (?) which I wouldn't expect to work, ever. But then it also shouldn't crash the kernel.
>
> A valid command would be efibootmgr -b 0003 -B
>

-B -b 0 seems to be the same as -B -b 0000, and my 0000 isn't the same
as your 0000 :)  The kernel crash is something else, in any case.

>
>
>>
>>>
>>>> or, even better, if anaconda's bootloader
>>>> installation process were factored out into a command I could run.
>>>
>>> I don't understand what this means.
>>
>> Being able to do:
>>
>> $ sudo fedora-configure-bootloader
>>
>> would be awesome.  It would probably have to take some command line arguments.
>
> Something that properly deals with restoring shim, grub, grub.cfg, and NVRAM would be nice. But the NVRAM part might be a rat hole, seeing as some of the manufacturer NVRAM behaviors are pretty icky. And on top of that don't seem to have a good way for users to reset/wipe it. It's something I think the UEFI Forum ought to put in the standard and require it.

Anaconda does this somehow, I think.  Even just exposing that would be nice.

--Andy