Public bug reported: Happened after upgrading to 18.04 from 16.04. Ubuntu fails to boot with kernel 4.15 as well.
ProblemType: Package DistroRelease: Ubuntu 18.04 Package: linux-image-4.15.0-20-generic 4.15.0-20.21 ProcVersionSignature: Ubuntu 4.13.0-39.44-generic 4.13.16 Uname: Linux 4.13.0-39-generic x86_64 ApportVersion: 2.20.9-0ubuntu7 AptOrdering: linux-image-4.15.0-20-generic:amd64: Remove NULL: ConfigurePending Architecture: amd64 Date: Tue May 29 16:12:20 2018 DpkgTerminalLog: Removing linux-image-4.15.0-20-generic (4.15.0-20.21) ... Failed to create or replace /vmlinuz.old: Is a directory at /usr/bin/linux-update-symlinks line 72. dpkg: error processing package linux-image-4.15.0-20-generic (--remove): installed linux-image-4.15.0-20-generic package post-removal script subprocess returned error exit status 21 DuplicateSignature: package:linux-image-4.15.0-20-generic:4.15.0-20.21 Removing linux-image-4.15.0-20-generic (4.15.0-20.21) ... Failed to create or replace /vmlinuz.old: Is a directory at /usr/bin/linux-update-symlinks line 72. dpkg: error processing package linux-image-4.15.0-20-generic (--remove): installed linux-image-4.15.0-20-generic package post-removal script subprocess returned error exit status 21 ErrorMessage: installed linux-image-4.15.0-20-generic package post-removal script subprocess returned error exit status 21 InstallationDate: Installed on 2016-05-10 (748 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) Python3Details: /usr/bin/python3.6, Python 3.6.5, python3-minimal, 3.6.5-3 PythonDetails: /usr/bin/python2.7, Python 2.7.15rc1, python-minimal, 2.7.15~rc1-1 RelatedPackageVersions: dpkg 1.19.0.5ubuntu2 apt 1.6.1 SourcePackage: linux-signed Title: package linux-image-4.15.0-20-generic 4.15.0-20.21 failed to install/upgrade: installed linux-image-4.15.0-20-generic package post-removal script subprocess returned error exit status 21 UpgradeStatus: Upgraded to bionic on 2018-05-05 (24 days ago) ** Affects: linux-signed (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-package bionic -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1773990 Title: package linux-image-4.15.0-20-generic 4.15.0-20.21 failed to install/upgrade: installed linux-image-4.15.0-20-generic package post- removal script subprocess returned error exit status 21 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed/+bug/1773990/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs