Re: UEFI GRUB boot menu disappears after booting into Windows 8

[Chris Murphy]

On Jan 13, 2013, at 1:24 PM, Joan Jerez <address@hidden> wrote:

> Hello,
> 
> After 6 January of 2013, I started to get problems when I boot into Windows 
> 8, and upon restart or shutdown, GRUB disappears and it boots directly into 
> Windows.

GRUB appears, shows you what, before disappearing and booting Windows? Can you 
interrupt this by pressing ESC or SHIFT (some versions apparently stop on GRUB 
with shift, others esc). Then can you type c <enter> to get a grub prompt, then 
type set <enter>.

You can either take a photo of the results from the 'set' command, or you can 
just type out the results for 
local-dir=
prefix=
root=
saved_entry=
secondary_locale_dir=


> I tried to remove (moving to another place) EFI applications related to 
> Microsoft (after installing Ubuntu, they are named bootmgfw.efi.bkp and 
> bootx64.efi.bkp) to ensure that they are not interfere with booting. As far I 
> can remember they are in /boot/efi/EFI/Boot and 
> /boot/efi/EFI/Microsoft/Boot/, now these folders are populated by GRUB2 EFI 
> applications.
> 
> The problem isn't solved by doing so, so UEFI firmware is not escaping GRUB 
> and booting directly using MS bootloader.
> Curiously, a long workaround is change booting method from UEFI to Legacy, 
> boot to a CD/DVD, or USB, shutdown, and change it again to UEFI, and GRUB 
> miraculously appears again.
> 
> 
> GRUB2 efi files are dated 3-01-2013 (I installed Kubuntu before, in 
> December), and I don't know if it's a regression because it don't happened 
> before.
> I don't know too where to get a older version of bootx64.efi of GRUB2 to test 
> if problem is solved.

This is complicated in part by the fact the grubx64.efi file has settings baked 
into the file itself. So you can actually get different behaviors, not based on 
the version of grub, but based on the settings in the grubx64.efi application 
itself. Those settings occur at the time grub-install creates the grubx64.efi 
file. Even if you move the grubx64.efi file around, it's almost invariably 
going to find a specific grub.cfg.

What *should* be the case for UEFI, is that each operating system has its own 
EFI boot load. And your firmware presents to you a list of available OS's to 
boot from, so in effect you use the firmware's boot manager to choose a boot 
loader which in turn is configured to boot an operating system.

I find it immensely overly complicated and fragile on UEFI to use GRUB as a 
boot manager for other boot loaders. *shrug*

Also, the location and efi file name /EFI/BOOT/bootx64.efi is special. The 
firmware is supposed to always run that application as its default. So if 
that's the Windows bootx64.efi then Windows always boots, you never get a GRUB 
menu. There is no one single bootx64.efi, it's a special filename to be used 
for the default efi boot application. It could even be a shell application 
rather than a boot loader, or a maintenance program, etc. So based on that file 
name you don't actually know what it is.

Chris Murphy