On Thu, Feb 14, 2019 at 10:44:34PM -0000, Marek Hák wrote:
> The output of 'efibootmgr -v' showed me where the EFI partition is, but
> I have no idea where it's mounted or how to get to it.
OK, this should be either sda2 or sdb2 depending on which order your disks
were detected. So you should be able to do sudo mount /dev/sda2 /boot/efi
to mount it (or /dev/sdb2, depending).
Then once you have replaced that grubx64.efi with the one that allows
booting unsigned kernels, you should run 'sudo umount /boot/efi' to make
sure the disk is cleanly unmounted. After this, you should have a
secureboot-enabled grub on the internal disk which allows you to boot to a
different unsigned kernel on the flash drive in order to reset the firmware
state.
> Thanks again for any help! I'd really love to sort this out :)
On Thu, Feb 14, 2019 at 10:44:34PM -0000, Marek Hák wrote:
> The output of 'efibootmgr -v' showed me where the EFI partition is, but
> I have no idea where it's mounted or how to get to it.
> Boot0004* ubuntu HD(2,GPT, 83484852- 541d-401e- 6a,0x1f4800, 0x82000) /File(\ EFI\ubuntu\ shimx64. efi)
> 84e7-6e6e854949
OK, this should be either sda2 or sdb2 depending on which order your disks
were detected. So you should be able to do sudo mount /dev/sda2 /boot/efi
to mount it (or /dev/sdb2, depending).
Then once you have replaced that grubx64.efi with the one that allows
booting unsigned kernels, you should run 'sudo umount /boot/efi' to make
sure the disk is cleanly unmounted. After this, you should have a
secureboot-enabled grub on the internal disk which allows you to boot to a
different unsigned kernel on the flash drive in order to reset the firmware
state.
> Thanks again for any help! I'd really love to sort this out :)
Sorry this is such a mess.