Crash due to fd leak when playing sounds in pidgin

Fix from https://hg.pidgin.im/pidgin/main/rev/902b1fd334bd

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

The attachment "remove-gstreamer-pipeline-after-playing-a-sound-902b1fd.diff" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

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Created bug 1529445, which is about a different fd leak in gstreamer 1.6.0 itself that can result in the exact same crash in pidgin as this bug.

It's not as straightforward as this bug in that it doesn't leak constantly for all users, but requires, for example, not having a sound card or some other error to play sounds (that's two different reports from users who got crashes).

Mentioning this here mostly because until today I thought this was yet another bug in pidgin that wasn't fixed, but no, it's a problem in gstreamer. Or rather, ubuntu in general, which doesn't do SRUs of bugfix-only releases until someone decides to point out that it's critical enough. *sigh*. Don't mind me, it's like 4am and I feel like I wasted most of my day with this dumb issue.

I ran into the same issue.

To improve searchability for this, the messages you see on the console from this are:

ERROR: cannot create wakeup pipe

(Pidgin:8924): GStreamer-CRITICAL **: gst_poll_get_read_gpollfd: assertion 'set != NULL' failed

(Pidgin:8924): GStreamer-CRITICAL **: gst_poll_write_control: assertion 'set != NULL' failed

(Pidgin:8924): GStreamer-CRITICAL **: gstsystemclock: write control failed in wakeup_async: 24:Too many open files

(Pidgin:8924): GStreamer-CRITICAL **: gst_poll_free: assertion 'set != NULL' failed

I see it nominated for wily, but it occurs in wily.

That's how bugs work here. They start as something for development versions only and then they are nominated to be fixed in stable releases.

Would disabling sound in Pidgin be a usefull workarround?

It could, but it would be unpleasant, as people like, when thet get an
audible "ping" when they've got a message.

Disabling all sounds but "Message received" and "Attention received" is the
best workaround for now - the amount of sounds are reduced to a fraction
compared to enabling online notifications and messages sent sounds.

A fix for this has been sitting in wily-proposed for about 3 weeks now. I have no idea what it takes to get through that into a regular update. It's been handled as Bug #1529445 so look there for more details. Maybe someone knows how to move it forward through the process?

> I have no idea what it takes to get through that into a regular update.

it needs somebody to install the update and verify it works as it should/fixes the problem it's supposed to/doesn't create regression and then comment back on launchpad saying that...

I haven't had access to my dev computer for a few weeks so I couldn't test that wily-proposed package yet. I would appreciate if someone else did - the test case in the description is fairly easy to set up, IMO.

However, note that bug #1529445 is not the same thing as this bug - the wily-proposed package won't fix this.

This bug is about a very specific fd leak introduced in ubuntu patches to pidgin 2.10.11. In wily this should be fixed with the attached patch. In xenial, by upgrading to 2.10.12 and removing those local gstreamer 1.0 patches.

The other bug is about completely different gstreamer fd leaks that in rare situations may have the same effect with pidgin.

The gstreamer leaks are less frequent. The ones from this bug happen on every sound that is played.

Thanks for the report and sorry for the delay, I'm updating xenial and uploaded a SRU for wily

Hello errors.ubuntu.com, or anyone else affected,

Accepted pidgin into wily-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/pidgin/1:2.10.11-0ubuntu4.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed 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 add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and 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 https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

Okay got my dev pc back and tested this.

The test case in the description is passing with the wily-proposed package, 2.10.11-0ubuntu4.1

Had to adjust the fd limit i originally suggested for the test to be more reliable - 20 was a bit too low and was sometimes failing during startup even, so I used 40 instead - but it always returns to the original number so there's no leak.

Also tested in combination with the new gstreamer packages, and in a VM with no sound - I think that covers every known fd leak source.

Thanks!

This bug was fixed in the package pidgin - 1:2.10.11-0ubuntu4.1

---------------
pidgin (1:2.10.11-0ubuntu4.1) wily; urgency=medium

  * debian/patches/hg_gst_leak.patch:
    "When receiving an error or stream finished message, we can free the
     Gstreamer pipeline so we don't leak it for each sound." (lp: #1479715)

 -- Sebastien Bacher <email address hidden> Tue, 23 Feb 2016 11:38:09 +0100

The verification of the Stable Release Update for pidgin 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 regressions.