Ubuntu
grub2 package

  1. Bug #1024383
  2. Comment #25

Comment 25 for bug 1024383

Revision history for this message
YannUbuntu (yannubuntu) wrote :

> At update-grub time, you know if you are EFI and should search for an EFI bootable windows.

No, don't rely on the mode where grub-update is used !
Counter-examples:
1) Windows is installed in UEFI mode but update-grub is used from a Ubuntu32bit liveCD (which cannot be booted in UEFI mode, see Bug #1025555 ).
2) Windows is installed in UEFI mode, but update-grub is used from a Legacy mode live-session because the BIOS is set up to boot the CD/USB in Legacy mode
3) Windows is installed in Legacy mode, but update-grub is used from an UEFI mode live-session because the BIOS is setup to boot the CD/USB in UEFI mode.

> an EFI booting system can't have a bios booting windows install.

I am nearly sure of the contrary, because many preinstalled Windows come with both files to be booted in UEFI and Legacy modes.
Examples: http://paste.ubuntu.com/1495850, http://paste.ubuntu.com/1479512 , http://paste2.org/p/2700549