Comment # 11 on bug 1127481 from Josef Reidinger

(In reply to Neil Rickert from comment #10)
> I'll try this again.  My first attempt to comment was botched (bad gateway
> message).
> 
> Comment #6 >Perhaps the kernel guys can help here in order to find out why
> it is booted via EFI.
> 
> This is a mistake.  The kernel is not involved.  Whether the DVD is booted
> with UEFI or legacy booting is between the user and the BIOS settings.  By
> the time the boot menu (for the DVD) is showing, it has already been
> determined whether to use UEFI or legacy booting.  And the kernel has not
> yet been loaded at that stage.
> 
> If you find yourself in this situation, go into bootloader settings (during
> the install), and change the bootloader from "grub2-efi" to "grub2".  Then
> legacy booting will be used.
> 
> Perhaps there could be an option screen for this.  When the update finds
> that it is updating a legacy-boot system, but the DVD (or USB) was booted
> with UEFI, maybe it could prompt the user to choose between legacy booting
> (as previously used) and UEFI booting (as the installer was booted).

Yeah, but only this way should be possible, as other case when originally EFI
is used and now DVD booted with legacy is not possible due to missing EFI
firmware variables.

In general this case is quite corner case which usually does not happen. It
really has nothing to do with kernel, as it is up to machine firmware if legacy
or EFI boot is used. YaST can only react on it.
So in case of legacy system and EFI booted medium it can allow user to force
install of legacy grub and it should work. In other case we have problem and
probably force user to boot properly DVD.