Bug#808366: grub-efi-amd64 -- error: symbol 'grub_efi_find_last_device_path' not found

[Colin Watson]

Control: severity -1 important

On Sat, Dec 19, 2015 at 09:11:09AM -0600, S. R. Wright wrote:
> On 12/19/2015 09:03 AM, Colin Watson wrote:
> >>On a system that dual boots Linux and Windows 10, the latest grub-efi gives
> >>this error:
> >>
> >>error: symbol 'grub_efi_find_last_device_path' not found
> >>
> >>when attempting to boot Windows 10 after an update-grub is performed.  Linux
> >>will boot correctly;  however,  an attempt to boot Windows 10 will give this
> >>error and say "press any key..." and bring one back to the OS menu.
> >>
> >>There is a workaround, which is to downgrade back to 2.02~beta2-32, and
> >>Windows will boot correctly.
> >This clearly indicates that GRUB is incorrectly installed in some way,
> >because you could only get a symbol mismatch such as this if the GRUB
> >image you're actually booting from doesn't match the modules it tries to
> >load from /boot/grub/ at run-time.  I would suggest digging around in
> >your EFI System Partition to see if there's a manually-copied version in
> >there somewhere.
> 
> I definitely did not copy anything manually into the EFI System Partition;
> if a rogue file got into there -- or if something didn't get updated there
> that should have -- it happened via process.  A downgrade back to 32 worked
> fine,  an upgrade to 33 broke down, bothe of these performed using
> dpkg/apt-get.  About all I can say.

Well, I'm afraid it's still going to need you to investigate along those
lines, because there's basically only one cause for symbol mismatches
like this and it's an incorrect installation of GRUB, rather than a
fault in the new version per se.  Perhaps you could start by providing
the output of "find /boot/efi -ls", as well as all the information you
have on the way your system boots?  If you have the terminal transcript
from the last time GRUB was updated (it will probably be in
/var/log/apt/term.log somewhere), then that would also be of some help.

-- 
Colin Watson                                       [cjwatson at debian.org]