Re: grub-lnstall option (UEFI) for chainloading

[Barry Jackson]

On 12/10/15 10:31, Andrei Borzenkov wrote:
> On Tue, Sep 8, 2015 at 12:39 AM, Barry Jackson <address@hidden> wrote:
> > On 06/06/15 09:38, Andrei Borzenkov wrote:
> > > В Fri, 05 Jun 2015 14:56:20 +0100
> > > Barry Jackson <address@hidden> пишет:
> >
> >
> > > > Any progress on this?
> > >
> > >
> > > Not really, sorry. Do you have any suggestion how such option should be
> > > named?
> >
> > Sorry for delay - this got lost in the noise.
> >
> > Well something like --no-id-or-nvram ??
> >
> > Not really bothered about the name! :)
>
> I was about to suggest a patch when I realized that this probably is
> currently useless on EFI. I.e. to actually chainload grub on EFI it
> must reside on a partition accessible by firmware which practically
> means it should be ESP.
>
> Unless someone submits patch to make grub2 EFI core.img multiboot2
> compliant with tag to skip ExitBootServices.
>
> Does chainloading from /boot/grub actually work for you on EFI? Could
> you explain your configuration in more details?

Sorry for the long delay I missed your reply. We could really do with a 
patch for this as Mageia 6 is in freeze. ;)

Yes it works fine from a separate small grub2 partition.

The grub2 install to the small dedicated grub2 partition is installed by 
my script here: https://wiki.mageia.org/en/User_talk:Barjac

This is my current grub.cfg created by the script:

set default="0"
set timeout=10

if loadfont unicode ; then
  set gfxmode=1024x768x32
  insmod all_video
  insmod gfxterm
  set locale_dir=/locale
  set lang=en_GB
  insmod gettext
fi
terminal_output gfxterm
insmod part_gpt
insmod ext2

# Theme
insmod gfxmenu
loadfont /grub2/themes/maggy/MageiaLogo-Bold-16.pf2
loadfont /grub2/themes/maggy/MageiaLogo-Bold-20.pf2
loadfont /grub2/themes/maggy/MageiaLogo-Bold-28.pf2
loadfont /grub2/themes/maggy/MageiaLogo-Regular-20.pf2
insmod png
set theme=/grub2/themes/maggy/theme.txt
export theme

menuentry 'Mageia 6 on /dev/sda7' {
search --no-floppy --fs-uuid --set=root 
"a5ea7e67-7d24-4ecd-8271-fe662c87f258"
chainloader /boot/grub2/x86_64-efi/core.efi
}

menuentry 'Mageia 5  on /dev/sda4' {
search --no-floppy --fs-uuid --set=root 
"6e0e6790-c318-4bbe-b3cf-e925391b4d16"
chainloader /boot/grub2/x86_64-efi/core.efi
}

menuentry 'Mageia 6  on /dev/sda5' {
search --no-floppy --fs-uuid --set=root 
"18c8d8d4-dee6-4219-9dbf-a96d439ea76e"
chainloader /boot/grub2/x86_64-efi/core.efi
}