This is not a bug in unattended-upgrades, but u-u triggers the problem in many packages which are not able to install/upgrade during a system shutdown.
Helper scripts in init-system-helpers must not start services when maintainer scripts are executed during shutdown and maintainer scripts must use helper scripts and not call systemct and friends directly to start services. Snapd for example calls systemctl start "$unit" in postinst. Thank you for the bug report. I marked it "Confirmed for u-u" to not let it disappear, but u-u is just triggering the issue and it can't be fixed in u-u. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unattended-upgrades in Ubuntu. https://bugs.launchpad.net/bugs/1778219 Title: unattended-upgrades hangs on shutdown, leaves system in a broken state Status in init-system-helpers package in Ubuntu: New Status in snapd package in Ubuntu: New Status in unattended-upgrades package in Ubuntu: Confirmed Bug description: When using unattended-upgrades with "InstallOnShutdown" on Bionic, the package installation on various packages hangs until the systemd ShutdownTimeout (30min) is expired and systemd kills all processes and powers off/reboots the system. This leaves packages in an unconfigured, broken state. At least sometimes this cannot be fixed with a "dpkg --configure -a", but instead requires the user to manually reinstall the package that caused the hang. This appears to be a deadlock, because the hanging commands are always "systemctl stop ..." or "systemctl restart ...", etc.. If I understand this correctly, those systemctl commands block because systemd tries to shutdown the system and tries to satisfy all dependencies for the shutdown targets before those systemctl commands could get executed, which creates a deadlock. Steps to reproduce: - Install 18.04 - activate "InstallOnShutdown" in /etc/apt/apt.conf.d/50unattended-upgrades - disable bionic-updates in /etc/apt/sources.list (more on that later) - execute "unattended-upgrade --download-only" - reboot the system -> The upgrade on shutdown hangs when configuring the apport package. The hanging command is "systemctl stop apport-forward.socket". The system hangs until the systemd ShutdownTimeout expires and systemd forcefully reboots the system. After the system is rebooted the apport package is in "iUR" state, and needs to be reinstalled to fix this. I disabled the bionic-updates pocket in sources.list, because in the default configuration unattended-updates does not use bionic-updates, and seems to have skipped installation of apport from bionic-security (supposedly because an already newer version of apport was in bionic- updates). If my understanding of why apport initially did not get installed is correct, then this would be another problem, because it would mean that unattended-upgrades potentially does not install all available security updates when bionic-updates is enabled in sources.list (which is the default). The problem can also be reproduced without disabling bionic-updates in sources.list, but instead enabling bionic-updates in /etc/apt/apt.conf.d/50unattended-upgrades. Then, in my case, the upgrade did hang when installing the package snapd (the hanging command was "systemctl stop snapd.autoimport.service snapd.core-fixup.service snapd.service snapd.snap-repair.service snapd.snap-repair.service snapd.socket snapd.system-shutdown.service"). This leads to the same problems as described above. --- ApportVersion: 2.20.9-0ubuntu7.1 Architecture: amd64 CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 18.04 InstallationDate: Installed on 2018-06-22 (0 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) Package: unattended-upgrades 1.1ubuntu1 PackageArchitecture: all ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17 Tags: bionic Uname: Linux 4.15.0-20-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/init-system-helpers/+bug/1778219/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
