gnome-panel crashed with signal 5 in _XReply()

[Ron Affeldt]

[Impact]

* Games using the Unity engine (like KSP) cause gnome-panel to crash, making things like flashback unusable.

[Test Case]

* Run gnome-panel (like in gnome flashback).

* Launch Kerbal Space Program. Not sure whether there's a simpler test case for those without KSP.

[Regression Potential]

* The patch for the bug suggests the possibility of weirdly colored icons where crashes used to occur.

[Other Info]

* libwnck3 (3.14.0-1) allows gnome-panel to continue running in 14.10.

ProblemType: Crash
DistroRelease: Ubuntu 14.04
Package: gnome-panel 1:3.8.0-1ubuntu9
ProcVersionSignature: Ubuntu 3.13.0-17.37-generic 3.13.6
Uname: Linux 3.13.0-17-generic x86_64
ApportVersion: 2.13.3-0ubuntu1
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Mar 16 23:53:20 2014
ExecutablePath: /usr/bin/gnome-panel
GsettingsChanges:

InstallationDate: Installed on 2014-02-28 (16 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20140224)
ProcCmdline: gnome-panel
ProcEnviron:
 LANGUAGE=de_DE
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
Signal: 5
SourcePackage: gnome-panel
StacktraceTop:
 ?? () from /usr/lib/x86_64-linux-gnu/libX11.so.6
 ?? () from /usr/lib/x86_64-linux-gnu/libX11.so.6
 _XReply () from /usr/lib/x86_64-linux-gnu/libX11.so.6
 XSync () from /usr/lib/x86_64-linux-gnu/libX11.so.6
 ?? () from /usr/lib/x86_64-linux-gnu/libcairo.so.2
Title: gnome-panel crashed with signal 5 in _XReply()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo

[Apport retracing service (apport)]

StacktraceTop:
 XSync (dpy=0x125ed20, discard=discard@entry=0) at ../../src/Sync.c:44
 sync (display=0x1375200, display=0x1375200) at /build/buildd/cairo-1.13.0~20140204/src/cairo-xlib-surface-shm.c:461
 _cairo_xlib_surface_update_shm (surface=surface@entry=0x1d33c00) at /build/buildd/cairo-1.13.0~20140204/src/cairo-xlib-surface-shm.c:952
 _cairo_xlib_surface_get_shm (surface=surface@entry=0x1d33c00, overwrite=overwrite@entry=0) at /build/buildd/cairo-1.13.0~20140204/src/cairo-xlib-surface-shm.c:1045
 _cairo_xlib_surface_acquire_source_image (abstract_surface=0x1d33c00, image_out=0x7fff95a544e0, image_extra=<optimized out>) at /build/buildd/cairo-1.13.0~20140204/src/cairo-xlib-surface.c:1394

[Dmitry Shachnev (mitya57)]

Thanks for your report. Do you know a way to reproduce this issue? Did you get it several times?

The stacktrace is good, but it looks like the error is not in gnome-panel itself, but probably in cairo.

[Launchpad Janitor (janitor)]

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

[Colombo (jirka678)]

Reported too:
https://bugs.launchpad.net/ubuntu/+source/gnome-panel/+bug/1361848

I don't know if this in cairo, but it is old bug thats been there for a year or more but was not properly reported.

It affect a lot of people and is easy to reproduce. It also happens every time one runs unity-based game.

[Andrew Skalski (askalski)]

Is there anything I can do to help troubleshoot this? I purchased Kerbal Space Program "early access" on Steam this morning, and gnome-panel crashes with this error whenever I try to run the game. This does not happen with the KSP demo, only the full version. A web search suggests this may affect any game that uses the Unity engine, not just KSP.

While KSP is running, any attempt to start up gnome-panel results in an immediate crash with this error output:

(gnome-panel:7495): Gdk-ERROR **: The program 'gnome-panel' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadMatch (invalid parameter attributes)'.
  (Details: serial 2047 error_code 8 request_code 62 (core protocol) minor_code 0)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the GDK_SYNCHRONIZE environment
   variable to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
Trace/breakpoint trap

I use "gnome-session-flashback" as my desktop environment on Ubuntu 14.10. The default desktop environment does not seem to be affected by this (I tried in a Guest session), but even in the Guest session you can still reproduce the error by attempting to execute "gnome-panel" in a terminal window while KSP is running.

If I install libcairo2-dbg and run gnome-panel with the GDK_SYNCHRONIZE environment variable, the crash occurs on line 905 of cairo-1.13.0~20140204/src/cairo-xlib-surface-shm.c when _cairo_xlib_surface_update_shm calls XCopyArea(). According to the XCopyArea docs at www.x.org, "The drawables must have the same root and depth, or a BadMatch error results." Unfortunately I am not versed in X programming, so I don't know what to try next.

[Alberts Muktupāvels (muktupavels)]

1. Remove window-list applet from bottom panel.
2. Try to launch game.

If gnome-panel does not crash then this might be bug in libwnck.

[Andrew Skalski (askalski)]

I still get the crash even after removing the window-list applet. I actually just finished building libwnck3-3.4.7 with this line commented out in libwnck/xutils.c in the try_pixmap_and_mask() function, and it successfully prevents the crash. I haven't noticed any side-effects other than some errors logged to my terminal:

  if (mask_surface)
    {
      //XXX cairo_mask_surface (cr, mask_surface, 0, 0);
      cairo_surface_destroy (mask_surface);
    }
  else
    cairo_paint (cr);

*** BUG ***
In pixman_region32_init_rect: Invalid rectangle passed
Set a breakpoint on '_pixman_log_error' to debug

[Alberts Muktupāvels (muktupavels)]

Then you can try to remove workspace switcher and/or show desktop applets - they are libwnck applets too.

Can you report this bug upstream?
https://bugzilla.gnome.org/enter_bug.cgi?product=libwnck

pixman errors are fixed in git master:
https://git.gnome.org/browse/libwnck/commit/?id=2fc0f058f00daf76c06e485c9d39491513f48345

[Alberts Muktupāvels (muktupavels)]

Well this might be fixed upstream:
https://git.gnome.org/browse/libwnck/commit/?id=5f88636284154e76611012c8a7c7495b9d917bd7

Can you build libwnck from git master and test if error is fixed?

[Andrew Skalski (askalski)]

The libwnck git master works perfectly.

I can also confirm that specific commit (5f88636284154e76611012c8a7c7495b9d917bd7) constitues the fix: applying the diff to libwnck3_3.4.7-3.debian fixes the crash; conversely, reverting the diff on git master reintroduces the crash.

[Alberts Muktupāvels (muktupavels)]

Dmitry can you patch libwnck to fix this bug in vivid?

1) https://git.gnome.org/browse/libwnck/commit/?id=5f88636284154e76611012c8a7c7495b9d917bd7
2) https://git.gnome.org/browse/libwnck/commit/?id=eddfee28c623fd7f4a0b6e38373798f96121e445

And maybe backport all patches from vivid to utopic?
1) Fix for this bug
2) Fix for pixman errors
3) Fix for missing icons

[Colombo (jirka678)]

Thank you, you are wonderful!
On 19/11/14 10:01, Andrew Skalski wrote:
> The libwnck git master works perfectly.
>
> I can also confirm that specific commit
> (5f88636284154e76611012c8a7c7495b9d917bd7) constitues the fix: applying
> the diff to libwnck3_3.4.7-3.debian fixes the crash; conversely,
> reverting the diff on git master reintroduces the crash.
>

[Launchpad Janitor (janitor)]

This bug was fixed in the package libwnck3 - 3.14.0-1

---------------
libwnck3 (3.14.0-1) experimental; urgency=medium

  * New upstream release.
    - Fixes crash when running some OpenGL apps (LP: #1293252).
  * Drop two patches from the previous upload, applied upstream.
  * Bump Standards-Version to 3.9.6, no changes needed.

 -- Dmitry Shachnev <email address hidden> Mon, 24 Nov 2014 17:01:23 +0300

[Jackson Doak (noskcaj)]

A fixed version can be obtained by installing ppa:noskcaj/libwnck3-sru . Can someone please test that?

[William Leiserson (willtor)]

I tested with your PPA on 14.10, and it works fine (no crash, no funky colors).

[Launchpad Janitor (janitor)]

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

[Dmitry Shachnev (mitya57)]

I have now uploaded the debdiffs for Trusty and Utopic, thanks Jackson and sorry for the delay.

(This bug was not in the sponsoring queue because the SRU tasks were missing.)

[Brian Murray (brian-murray)]

Hello Ron, or anyone else affected,

Accepted libwnck3 into utopic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/libwnck3/3.4.7-3ubuntu0.1 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!

[Brian Murray (brian-murray)]

Hello Ron, or anyone else affected,

Accepted libwnck3 into trusty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/libwnck3/3.4.7-0ubuntu3.1 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!

[Juha Erkkilä (juha-erkkila)]

Tested the following packages on Trusty from trusty-proposed:

ii libwnck-3-0:i386 3.4.7-0ubuntu3.1 i386 Window Navigator Construction Kit - runtime files
ii libwnck-3-common 3.4.7-0ubuntu3.1 all Window Navigator Construction Kit - common files

Those fix this bug for us, thank you!

[Launchpad Janitor (janitor)]

This bug was fixed in the package libwnck3 - 3.4.7-0ubuntu3.1

---------------
libwnck3 (3.4.7-0ubuntu3.1) trusty; urgency=medium

  * Add git_support_non-standard_depths_for_icon_pixmaps.patch,
    git_correctly_link_against_libXrender.patch:
    - fixes a crash when using non-standard depths. LP: #1293252
 -- Jackson Doak <email address hidden> Sat, 31 Jan 2015 13:34:28 +1100

[Dmitry Shachnev (mitya57)]

Can anybody test the fix on Utopic (14.10) please?