Ubuntu
grub2 package

  1. Bug #1091464
  2. Comment #10

Comment 10 for bug 1091464

Revision history for this message
Martin Haynes (martin-haynes) wrote : Re: Unable to chainload Windows 8 with Secure Boot enabled

Confirmed on Samsung Series 7.

I renamed /EFI/Microsoft/Boot/bootmgfw.efi as /EFI/ubuntu/grubx64.efi to confirm that no keystore or signature validation issues were at work during the Secure Boot failures. This worked as expected, booting win2k12 without issue. **Note that this test obviously makes grub unavailable on reboot. I wouldn't suggest anyone attempt this with an in-use install.

I then performed a clean install of 13.04 to backing out the signed grub efi loaders and boot-repair changes, disabled os-probing and did a sudo update-grub to clean up the loader menu.

Finally, my work around was also to rely on the EFI NVRAM configuration but instead of simply relying on shuffling between HDD and "ubuntu", I created new efibootmgr entries for Windows 8 and my recovery partition. So effectively, I am now using the UEFI POST menu as a boot loader.

Hopefully, the Samsung nvram bug and the resulting (unwanted) attention will mean a quick fix.