Ubuntu
appmenu-qt package

python3.3 crashed with SIGSEGV in QWidget::destroy()

Bug #1273306 reported by Martin Pitt on 2014-01-27

20

This bug affects 3 people

Affects		Status	Importance	Assigned to	Milestone
	window-mocker	New	Undecided	Unassigned
	appmenu-qt (Ubuntu)	Invalid	Undecided	Łukasz Zemczak
	qtbase-opensource-src (Ubuntu)	Fix Released	Undecided	Łukasz Zemczak

Bug Description

This happens when trying to run window-mocker with python3:

$ bzr branch lp:~coreygoldberg/window-mocker/py3
$ cd py3
$ PYTHONPATH=. python3 bin/window-mocker -t Qt5

When merely closing the window it cleanly exits for me; but when resizing the window I get this crash.

ProblemType: Crash
DistroRelease: Ubuntu 14.04
Package: python3.3-minimal 3.3.3-6
ProcVersionSignature: Ubuntu 3.13.0-5.20-generic 3.13.0
Uname: Linux 3.13.0-5-generic x86_64
ApportVersion: 2.13.2-0ubuntu1
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Jan 27 17:23:52 2014
EcryptfsInUse: Yes
ExecutablePath: /usr/bin/python3.3
ExecutableTimestamp: 1389422324
InstallationDate: Installed on 2013-10-14 (105 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Beta amd64 (20131013)
ProcCmdline: python3 bin/window-mocker -t Qt5
ProcCwd: /home/martin/ubuntu/tmp/py3
SegvAnalysis:
Segfault happened at: 0x7ff6f44b994d <_ZN7QWidget7destroyEbb+637>: mov 0x8(%rax),%rdi
PC (0x7ff6f44b994d) ok
source "0x8(%rax)" (0x00000008) not located in a known VMA region (needed readable region)!
destination "%rdi" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: python3.3
StacktraceTop:
QWidget::destroy (this=this@entry=0x239d360, destroyWindow=destroyWindow@entry=true, destroySubWindows=destroySubWindows@entry=true) at kernel/qwidget_qpa.cpp:172
QWidget::~QWidget (this=0x239d360, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1478
QMenu::~QMenu (this=0x239d360, __in_chrg=<optimized out>) at widgets/qmenu.cpp:1362
MenuBarAdapter::~MenuBarAdapter() () from /tmp/apport_sandbox_qceHPQ/usr/lib/x86_64-linux-gnu/qt5/plugins/menubar/libappmenu-qt.so
AppMenuPlatformMenuBar::destroyMenuBar() () from /tmp/apport_sandbox_qceHPQ/usr/lib/x86_64-linux-gnu/qt5/plugins/menubar/libappmenu-qt.so
Title: python3.3 crashed with SIGSEGV in QWidget::destroy()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm autopilot cdrom dip lpadmin plugdev sambashare sbuild sudo

Tags:

Related branches

lp://qastaging/~sil2100/kubuntu-packaging/qtbase-opensource-src_5.0.2_qapp_fix

Merged into lp://qastaging/~kubuntu-packagers/kubuntu-packaging/qtbase-opensource-src_5.0.2

Timo Jyrinki: Approve on 2014-02-04

lp://qastaging/~kubuntu-packagers/kubuntu-packaging/qtbase-opensource-src

Revision history for this message

Martin Pitt (pitti) wrote on 2014-01-27:

#1

Dependencies.txt Edit (1.0 KiB, text/plain; charset="utf-8")
Disassembly.txt Edit (1.4 KiB, text/plain; charset="utf-8")
ProcEnviron.txt Edit (100 bytes, text/plain; charset="utf-8")
ProcMaps.txt Edit (64.9 KiB, text/plain; charset="utf-8")
ProcStatus.txt Edit (839 bytes, text/plain; charset="utf-8")
Registers.txt Edit (703 bytes, text/plain; charset="utf-8")
Stacktrace.txt Edit (29.8 KiB, text/plain; charset="utf-8")
StacktraceSource.txt Edit (7.6 KiB, text/plain; charset="utf-8")
ThreadStacktrace.txt Edit (37.8 KiB, text/plain; charset="utf-8")

Revision history for this message

Launchpad Janitor (janitor) wrote on 2014-01-27:

#2

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

Changed in python3.3 (Ubuntu):
status:	New → Confirmed

Revision history for this message

Martin Pitt (pitti) wrote on 2014-01-27:

#3

This goes through libappmenu-qt, so I tried under env -u UBUNTU_MENUPROXY. It still crashes, but less often. But the stack trace in that case looks very similar, in particular it goes through the same libappmenu-qt.so functions.

Revision history for this message

Martin Pitt (pitti) wrote on 2014-01-27:

#4

I confirm that if I uninstall appmenu-qt5, the crash goes away. Changing package to appmenu-qt5 tentatively.

affects:	python3.3 (Ubuntu) → appmenu-qt (Ubuntu)
Changed in appmenu-qt (Ubuntu):
status:	Confirmed → New

Revision history for this message

Łukasz Zemczak (sil2100) wrote on 2014-01-29:

#5

Looking into it right now. Due to the small number of Qt5 applications available for our platform, the new appmenu-qt5 might still have some bugs in it. I never tested it with python qt5 before, so I might have missed something there. Let me see what's up.

Changed in appmenu-qt (Ubuntu):
assignee:	nobody → Łukasz Zemczak (sil2100)
status:	New → In Progress

Revision history for this message

Łukasz Zemczak (sil2100) wrote on 2014-01-29:

#6

Could I get some more information on this bug? How did you reproduce it? When installing Qt 5.2 I no longer have a python3-pyqt5 install candidate, as it depends on libqt5core5 (instead of libqt5core5a) - and I didn't see a successful rebuild against Qt 5.2 anywhere. What version of python3-pyqt5 did you use with 5.2? Where can I get it to test it properly?

Changed in appmenu-qt (Ubuntu):
status:	In Progress → Incomplete

Revision history for this message

Martin Pitt (pitti) wrote on 2014-01-29:

#7

This is not related to Qt 5.2, that isn't in trusty yet (that still has 5.0). I was just installing python3-pyqt5 5.2+dfsg-1ubuntu7 (current trusty version), checked out above window-mocker py3 branch, and run it as in the description.

Revision history for this message

Łukasz Zemczak (sil2100) wrote on 2014-01-29:

#8

Oh, ok that changes a lot. I was asking Corey about the details, and I asked about which Qt version is used - he said it's 5.2, so I thought the bug is related to the new QPA-based appmenu-qt5 I have been recently working on.

But it seems it's related to the old now-deprecated appmenu-qt then. There has not been a new version of the old appmenu-qt5 (for Qt 5.0.2) since a really really long while, so I guess it had to be broken for a longer time. I'll try reverting my Qt 5.2 and looking into this anyway.

Thanks!

Changed in appmenu-qt (Ubuntu):
status:	Incomplete → In Progress

Revision history for this message

Łukasz Zemczak (sil2100) wrote on 2014-01-29:

#9

Ok, I checked briefly the code and I see the problem, but I wonder if I can fix it in appmenu-qt or will have to do it otherwise. appmenu-qt is deprecated anyway, so the fix will have to be a distro-patch anyway. Let me finish this up tomorrow morning.

Łukasz Zemczak (sil2100) on 2014-01-31

Changed in qtbase-opensource-src (Ubuntu):
status:	New → In Progress
assignee:	nobody → Łukasz Zemczak (sil2100)

Revision history for this message

Dmitry Shachnev (mitya57) wrote on 2014-01-31:

#10

FWIW, PyQt5 rebuilt against Qt 5.2 is now available in ppa:canonical-qt5-edgers/qt5-beta2.

rosa maria (rprosamaria383) on 2014-02-03

Changed in window-mocker:
assignee:	nobody → rosa maria (rprosamaria383)
assignee:	rosa maria (rprosamaria383) → nobody

Revision history for this message

Łukasz Zemczak (sil2100) wrote on 2014-02-06:

#11

So, the fix will be landing in the archive today.

Changed in appmenu-qt (Ubuntu):
status:	In Progress → Invalid
Changed in qtbase-opensource-src (Ubuntu):
status:	In Progress → Fix Committed

Revision history for this message

Launchpad Janitor (janitor) wrote on 2014-02-06:

#12

This bug was fixed in the package qtbase-opensource-src - 5.0.2+dfsg1-7ubuntu18

---------------
qtbase-opensource-src (5.0.2+dfsg1-7ubuntu18) trusty; urgency=medium

  [ Albert Astals ]
  * Add 0001-Do-not-overwrite-basePixmap-of-QIconLoader-PixmapEnt.patch:
    - Backport an upstreamed fix to blurry icons (LP: #1271158)

  [ Łukasz 'sil2100' Zemczak ]
  * Add fix_destroy_qapp_segfault.diff:
    - Fix a segfault when QWidget element gets freed after the main
      application exits. Do not assume qApp is present. It's already
      fixed in upstream Qt 5.2 (LP: #1273306)
-- Timo Jyrinki <email address hidden> Thu, 06 Feb 2014 11:57:09 +0000

Changed in qtbase-opensource-src (Ubuntu):
status:	Fix Committed → Fix Released

Report a bug

This report contains Public information

Everyone can see this information.

You are

Subscribing...

Edit bug mail

Other bug subscribers

Bug attachments

Add attachment

Remote bug watches

Bug watches keep track of this bug in other bug trackers.