Mutter crashes every time I try to start Mumble

Hey Matt,
Can you give it a try with:
- indicator-appmenu 0.0.11-0ubuntu3
- unity 0.2.40 (available in few hours, currently in the build queue)

It contains some fixes related to crashing apps on open (on maximized, to be more precise).

Didier, this is *mutter* crashing, not mumble closing.

I've upgraded unity and can still confirm this bug. It's not 100% (with either version), but it's pretty reliable.

ii indicator-appmenu 0.0.11-0ubuntu3 Indicator for application menus.
ii unity 0.2.40-0ubuntu1 Unity Interface for Ubuntu Netbook Edition

GNOME terminal also crashed the last time Mutter went down.

@Rick: oupss, sorry, read too fast…

@mdz: I tried to made it crash under the GNOME session for easier debugging, but didn't get anything. We'll see if the dx team can get something out of there.
I'll try this week-end to make it crash under a less powerful host if it can raise a race somewhere…

(to start unity in GNOME, you can mutter --replace --mutter-plugins=/usr/lib/mutter/plugins/libunity-mutter.so

I tried with mutter only too and didn't get anything more.

@mdz Please do try with very latest unity, mutter and appmenu, as the fixes didrocks mentioned did touch precisely the code where your seeing the crash. Otherwise, if your running on an intel machine, starting unity from VT1 like this would give us a chance of a backtrace:

export DISPLAY=:0
export UBUNTU_MENUPROXY=libappmenu.so
gdb --args mutter --replace --mutter-plugins=libunity-mutter
(gdb) r <enter>

Then, switch to VT7 and, when it crashes, the screen should freeze and you can switch back to VT1 and hopefully get a trace. It's a pain to copy gdb traces off a VT, though, so having a camera handy is useful :)

On Mon, Sep 20, 2010 at 10:18:39AM -0000, Neil J. Patel wrote:
> @mdz Please do try with very latest unity, mutter and appmenu, as the
> fixes didrocks mentioned did touch precisely the code where your seeing
> the crash.

Which version of unity do you mean? I have confirmed the bug with
0.2.40-0ubuntu1 as Didier requested.

> Otherwise, if your running on an intel machine, starting unity from VT1
> like this would give us a chance of a backtrace:
> export DISPLAY=:0
> export UBUNTU_MENUPROXY=libappmenu.so
> gdb --args mutter --replace --mutter-plugins=libunity-mutter
> (gdb) r <enter>
>
> Then, switch to VT7 and, when it crashes, the screen should freeze and
> you can switch back to VT1 and hopefully get a trace. It's a pain to
> copy gdb traces off a VT, though, so having a camera handy is useful :)

I have a core dump, so I do have a backtrace. It just isn't very useful:

 #2 0x02d12e42 in abort () from /lib/libc.so.6
 #3 0x080920cc in meta_bug ()
 #4 0x0807a57f in ?? ()
 #5 0x010162c9 in _XError () from /usr/lib/libX11.so.6
 #6 0x0101d0de in _XReply () from /usr/lib/libX11.so.6
 #7 0x00ffa316 in XGetWindowProperty () from /usr/lib/libX11.so.6
 #8 0x098e05e4 in egg_xid_get_functions () from /usr/lib/indicators/3/libappmenu.so
[...]

i.e. it's dying because of the X error which you can see in the log.

I tried retracing the core file, but apport-retrace tells me that every one
of the -dbgsym packages are unavailable or incompatible for some reason.

--
 - mdz

hum, maybe linked to bug #641498 (seeing a crash in egg_xid_get_functions)

@mdz, actually, that's more than helpful, thanks :) I managed to reproduce it and got a good trace. It's because the appmenu is trying to access a window that no longer exists, causing the call to fail and mutter to abort. This bug (appmenu not having good references) is actually a cause of a lot of crashes and is being worked on by jason, so assigning to him.

The linked branch of appmenu should protect against BadWindow errors and stop Unity crashing. Initial testing seems to show good results but some more testing would be appreciated :)

If you do try it, either build a package to make absolutely sure this appmenu is being picked up, or install into /usr (otherwise they won't be loaded).

This bug was fixed in the package unity - 0.2.42-0ubuntu1

---------------
unity (0.2.42-0ubuntu1) maverick; urgency=low

  * New upstream release:
    - "Applications" and "Files & Folders" tooltips are not translatable
      (LP: #644215)
    - Fix inactive menus are accessible on switching to a window (LP: #604505)
    - Fix wrong launcher tile label/quicklist x position (LP: #631446)
    - Fix highlighted items in quicklist have different widths (LP: #643315)
    - In migration tool, being safe when people are using crazy caracters in
      desktop file (LP: #644114, #635156)
    - Detect if 3D acceleration support is provided. Otherwise, prompt for
      logout and change default session (LP: #614088)
    - Fix quicklist shows hidden menu items (LP: #641543)
    - Fix removing launchers via dnd fails (LP: #643434)
    - Better launcher auto-scroll performances (LP: #640560)
    - Make the insensitive state of the forward- and back-button more obvious by
      decreasing their opacity, thus users don't assume they are actually
      clickable. (LP: #638285)
    - Fix some dialogs aren't maximized but are undecorated (LP: #628822)
    - Fix some menus don't go away when window closes (LP: #640557)
    - Fixes bug where the wrong icon where at times associated with a tile in
      the places view. (LP: #642935)
    - Speedup icon loading (LP: #641246)
    - Make trash menu items in Unity are either not translatable or translations
      are not loaded (LP: #645038)
    - Fix using dnd on launcher makes focus not work out of the unity ui
      (LP: #637123)
    - Multi-monitor support (LP: #637123)
    - Enable/disable super key by a gconf key (LP: #632581)
    - Remove glow on fold (LP: #619344)
    - Ensure we dont map windows when expose is active (LP: #599766)
    - take new indicator API for action for top-level dropdown menu item not
      activated (LP: #637692)
    - Make the home buttons reactive (LP: #638857)
    - Add red tint when search fails (LP: #607821)
    - New (and final!) UI adjustement, but UNE isn't in the doc as seen with
      the doc team (LP: #627009)
    - Single-touches on the launcher are usually interpreted as a drag
      (LP: #641328)
    - URI activation in global view (LP: #612562)
    - Clicking a Place icon while viewing the same place in the Dash should
      return to the Home screen of that place and clear the search (LP: #607829)
    - Fix mutter crashed with SIGSEGV in g_type_check_instance() (LP: #641561)
    - Fix panel and menu item font colors don't match (LP: #637480)
    - Fix indicators have orange color (LP: #632975)
    - Fix inactive menus are accessible on switching to a window (LP: #604505)
    - Use semi-transparent rectangle around launcher-icon (LP: #643388)
    - Fix mutter crashes when closing pop-up dialog (LP: #642669)
    - Change launcher icon reference size loading (LP: #641669)
    - Fix mutter crashing in mumble start (LP: #641335)
    - Fix clicking on a category from CoFs does not directly take you to the
      desired category (LP: #638402)
    - Fix some menus don't go away when window closes (LP: #640557)
    - Launchers should act like if the application was not focussed ...