[Bug 1602536] Re: /usr/bin/unattended-upgrade:apt.cache.LockFailedException:/usr/bin/unattended-upgrade at 1468:main:do_auto_remove:cache_commit:commit:_fetch_archives

[Launchpad Bug Tracker]

This bug was fixed in the package unattended-upgrades -
1.1ubuntu1.18.04.1

---------------
unattended-upgrades (1.1ubuntu1.18.04.1) bionic; urgency=medium

  [ Michael Vogt ]
  * unattended-upgrades: fix Unlocked context manager. (LP: #1602536)
    The Unlocked context manager did correctly unlock but did not
    reacquire the lock which means that in minimal-upgrade step
    mode it is possible to run apt code without a lock. If something
    else (like landscape, apt, synaptic, packagekit) locks the cache
    in the meantime this will work and u-u will get dpkg errors
    because dpkg will not be able to perform its operations. It is
    less of an issue in non-minimal mode, but even then the auto-remove
    step may fail in this way.

  [ Balint Reczey ]
  * Fix adjusting candidates (LP: #1775292)
  * Relock apt lock before reopening the cache (LP: #1602536)
  * Fix crashing while adjusting candidates and save candidates to adjust only
    in first sweep run, not emptying the set later
    (Closes: #901258) (LP: #1775307)

 -- Balint Reczey <rbalint at ubuntu.com>  Wed, 06 Jun 2018 16:30:55 -0700

** Changed in: unattended-upgrades (Ubuntu Bionic)
       Status: Fix Committed => Fix Released

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to python-apt in Ubuntu.
https://bugs.launchpad.net/bugs/1602536

Title:
  /usr/bin/unattended-upgrade:apt.cache.LockFailedException:/usr/bin
  /unattended-
  upgrade at 1468:main:do_auto_remove:cache_commit:commit:_fetch_archives

Status in python-apt package in Ubuntu:
  Fix Committed
Status in unattended-upgrades package in Ubuntu:
  Fix Released
Status in python-apt source package in Xenial:
  New
Status in unattended-upgrades source package in Xenial:
  New
Status in python-apt source package in Bionic:
  New
Status in unattended-upgrades source package in Bionic:
  Fix Released

Bug description:
  [Impact]

   * Unattended-upgrades fails to autoremove packages after installing
  updates or fails to install updates due to a parallel process
  acquiring apt or dpkg lock while u-u is running.

  [Test Case]

   * Set up a system with packages (> 30) to be upgraded. In case of
  Bionic -security has a low number of updates, thus set up the system
  to install -updates to have more packages for u-u to upgrade:

   echo 'Unattended-Upgrade::Allowed-Origins::
  "${distro_id}:${distro_codename}-updates";' >
  /etc/apt/apt.conf.d/51-updates

   * Set up two shells to run commands in parallel
   * In shell "A" run sudo apt update && sudo unattended-upgrade --dry-run --verbose --debug
   * After u-u started run the following command in shell "B":
   while sleep 1; do python3 -c 'import apt; import apt_pkg; print(apt_pkg.pkgsystem_lock())' ; done
   * Observe the following exception repeated while running u-u and True being printed after u-u is finished:
  ...
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
  apt_pkg.Error: E:Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable), E:Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
  apt_pkg.Error: E:Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable), E:Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?
  True
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
  apt_pkg.Error: E:Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable), E:Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?
  True
  True
  True
  True
  ...

  [Regression Potential WIP]

   * Unattended-upgrade may crash

  [Other Info]

  It looks like python-apt also releases the lock sometimes unexpectedly
  thus the both packages need to be fixed to avoid loosing the lock.

  [Original Bug Text]

  The Ubuntu Error Tracker has been receiving reports about a problem
  regarding unattended-upgrades.  This problem was most recently seen
  with version 0.90, the problem page at
  https://errors.ubuntu.com/problem/19f99745d7dce5aea118eb31bfffcbdcdf238c4f
  contains more details.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/python-apt/+bug/1602536/+subscriptions