Comment 0 for bug 1800340

After an upgrade from 18.04 to 18.10 the installation of grub-efi-amd64-signed fails due to

``
Setting up grub-efi-amd64-signed (1.110+2.02+dfsg1-5ubuntu8) ...
Installing for x86_64-efi platform.
Could not prepare Boot variable: Invalid argument
grub-install: error: efibootmgr failed to register the boot entry: Input/output error.
dpkg: error processing package grub-efi-amd64-signed (--configure):
 installed grub-efi-amd64-signed package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
 grub-efi-amd64-signed
```

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: grub-efi-amd64-signed 1.110+2.02+dfsg1-5ubuntu8
ProcVersionSignature: Ubuntu 4.18.0-10.11-generic 4.18.12
Uname: Linux 4.18.0-10-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.10-0ubuntu13
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sun Oct 28 12:28:01 2018
SourcePackage: grub2-signed
UpgradeStatus: Upgraded to cosmic on 2018-10-21 (6 days ago)