session-installer crashed with AlreadyCalledDeferred in callback()

Bug #848605 reported by Khairul Nizam on 2011-09-13
This bug affects 6 people
Affects Status Importance Assigned to Milestone
sessioninstaller (Ubuntu)
Michael Terry

Bug Description


 * This can prevent users from installing helper packages needed to do their work (for example, can prevent opening rar, 7z, or jnlp files).

 * In addition, this is a highly reported crash on, so we know it affects many users.

 * The proposed fix just makes a certain deferral callback not be called twice, avoiding the assertion crash.


 * Unfortunately, I could not reproduce. So the patch is only based on code analysis. Someone that can reproduce needs to test it. I'm hoping by being accepted into precise-proposed, that will make it easier for the affected audience to test.

 * But the indicated reproduction steps as reported are:
0) Make sure you don't have rar installed: sudo apt-get purge rar unrar
1) Download a rar file. Try
2) Open that file with file-roller
3) Try to install the necessary packages to open it

[Regression Potential]

 * Regression potential is low. In the worst case, I could imagine if the patch is bogus, I could imagine the installation dialog would just stay open indefinitely because the deferral callback never got called.


The patch is simple:

--- sessioninstaller-0.20+bzr128.orig/sessioninstaller/backends/
+++ sessioninstaller-0.20+bzr128/sessioninstaller/backends/
@@ -44,12 +44,11 @@ class AptDaemonBackend(object):
     def _run_trans(self, trans, parent, interaction):
         deferred = defer.Deferred()
         dia = aptdaemon.gtk3widgets.AptProgressDialog(trans)
- dia.connect("finished", lambda x: deferred.callback())
         if parent:
             dia.set_transient_for(parent), show_error=True,
- reply_handler=lambda: True,
+ reply_handler=deferred.callback,
         return deferred


unable to do partial upgrade

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: sessioninstaller 0.20+bzr120-0ubuntu2
ProcVersionSignature: Ubuntu 3.0.0-11.17-generic 3.0.4
Uname: Linux 3.0.0-11-generic i686
ApportVersion: 1.22.1-0ubuntu2
Architecture: i386
Date: Tue Sep 13 12:58:04 2011
ExecutablePath: /usr/bin/session-installer
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta i386 (20110901)
InterpreterPath: /usr/bin/python2.7
PackageArchitecture: all
ProcCmdline: /usr/bin/python /usr/bin/session-installer
 PATH=(custom, no user)
PythonArgs: ['/usr/bin/session-installer']
SourcePackage: sessioninstaller
Title: session-installer crashed with AlreadyCalledDeferred in callback()
UpgradeStatus: Upgraded to oneiric on 2011-09-13 (0 days ago)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare

Khairul Nizam (khoirulniezam) wrote :
tags: removed: need-duplicate-check
Launchpad Janitor (janitor) wrote :

Status changed to 'Confirmed' because the bug affects multiple users.

Changed in sessioninstaller (Ubuntu):
status: New → Confirmed
visibility: private → public
HaddadR (hr-haddad) wrote :

 uname -a : Linux HP-Ub 3.2.0-23-generic #36-Ubuntu SMP Tue Apr 10 20:39:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

I tried to open a .rar file -> Ubuntu proposed to install Rar package -> installation crached

Håvard Gulldahl (havard) wrote :

Ditto -- in my case a 7z archive

Corey Whitaker (whitaker-corey) wrote :

I just had the same bug. As someone else stated, I was using the Ubuntu tool for finding software to open a file (in this case a JNLP file.) I was asked to authenticate, I'm positive I typed my password correctly but it didn't authenticate. I tried 2 more times and then the program crashed.

tags: added: precise
Changed in sessioninstaller (Ubuntu):
importance: Undecided → Medium

I installed the 12 version of ubuntu and after a few hours the message of internal error in a first locked the notebook and a desktop, could not even operate more machines. Because of this reinstalled the OS and the same problem persists .. what is happening ... need to respond because I want to install ubuntu on the machines of the school work

Sebastien Bacher (seb128) wrote :

Hey Michael, that bug is one of the frequent issue we get on, is there any chance you could have a look to it?

Changed in sessioninstaller (Ubuntu Precise):
importance: Undecided → High
milestone: none → ubuntu-12.04.1
assignee: nobody → Michael Terry (mterry)
Changed in sessioninstaller (Ubuntu Precise):
status: New → Triaged
Changed in sessioninstaller (Ubuntu):
status: Confirmed → Triaged
Steve Kroon (kroon) wrote :

I got referred to this bug by my system. Before that, Rhythmbox had prompted me if I wanted to install plugins, and it was trying to install them. This failed with the error message below. Other possibly relevant information: at the time this happened, the Update Manager was open (but not active - i.e. not downloading/installing updates).

Error message:

session-installer (Window Title)

An unhandlable error occured

There seems to be a programming error in aptdaemon, the software that allows you to install/remove software and to perform other package management related tasks.


org.freedesktop.DBus.Error.NoReply: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

Michael Terry (mterry) wrote :

I just can't reproduce this, using the try-to-open-a-rar method. Does anyone have reliable reproduction steps?

I do have a guess though. Will upload a package to precise-proposed for testing for those that this does affect.

Michael Terry (mterry) wrote :

Before that package lands for testing, the adventurous can try putting this file in /usr/share/pyshared/sessioninstaller/backends/

Changed in sessioninstaller (Ubuntu Precise):
status: Triaged → In Progress
Scott Kitterman (kitterman) wrote :

Needs to have the proper elements of an SRU in the bug before accepting:

Changed in sessioninstaller (Ubuntu Precise):
status: In Progress → Incomplete
Michael Terry (mterry) on 2012-07-30
description: updated

Hello Khairul, or anyone else affected,

Accepted sessioninstaller into precise-proposed. The package will build now and be available at in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please change the bug tag from verification-needed to verification-done. If it does not, change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at . Thank you in advance!

Changed in sessioninstaller (Ubuntu Precise):
status: Incomplete → Fix Committed
tags: added: verification-needed
Steve Langasek (vorlon) wrote : shows no instances of this error with the version in precise-proposed, vs. over 3000 in the month of August with the previous version. As we do see numerous crash reports for bugs present in precise-proposed, the fact that there have been no reports at all seems to be ample evidence that the bug is fixed.

tags: added: verification-done
removed: verification-needed
Launchpad Janitor (janitor) wrote :

This bug was fixed in the package sessioninstaller - 0.20+bzr128-0ubuntu1.1

sessioninstaller (0.20+bzr128-0ubuntu1.1) precise-proposed; urgency=low

  * debian/patches/fix-defer-callback.patch:
    - Make sure not to accidentally call defer.callback() twice
      (LP: #848605)
 -- Michael Terry <email address hidden> Mon, 23 Jul 2012 16:18:37 -0400

Changed in sessioninstaller (Ubuntu):
status: Triaged → Fix Released

The verification of this Stable Release Update has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regresssions.

Launchpad Janitor (janitor) wrote :

This bug was fixed in the package sessioninstaller - 0.20+bzr128-0ubuntu1.1

sessioninstaller (0.20+bzr128-0ubuntu1.1) precise-proposed; urgency=low

  * debian/patches/fix-defer-callback.patch:
    - Make sure not to accidentally call defer.callback() twice
      (LP: #848605)
 -- Michael Terry <email address hidden> Mon, 23 Jul 2012 16:18:37 -0400

Changed in sessioninstaller (Ubuntu Precise):
status: Fix Committed → Fix Released
Martin Pitt (pitti) wrote :

This was not yet in trunk, I committed it now under Michael's name (r130).

To post a comment you must log in.
This report contains Public information  Edit
Everyone can see this information.

Duplicates of this bug

Other bug subscribers