dconf-service crashed with signal 5 in __libc_start_main()

[Rick Gatewood]

I have been getting this crash for a few months about once a day. Now, since upgrading to 12.04 it is happening two or three times a day. So far, it seems more annoying than troublesome, but I would prefer not having it pop up all day long.

I am running gnome-shell on system that was upgraded from 11.10.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: dconf-service 0.12.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu7
Architecture: amd64
Date: Thu May 3 11:39:33 2012
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100427.1)
SourcePackage: d-conf
UpgradeStatus: Upgraded to precise on 2012-04-15 (17 days ago)

[Launchpad Janitor (janitor)]

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

[Luc Bruninx (luc2005)]

I have the same problem a little time after login my session in Unity.

I note this in my apport log:

ERROR: apport (pid 2272) Tue Sep 25 09:02:13 2012: called for pid 2271, signal 5
ERROR: apport (pid 2272) Tue Sep 25 09:02:13 2012: executable: /usr/lib/dconf/dconf-service (command line "/usr/lib/dconf/dconf-service")
ERROR: apport (pid 2272) Tue Sep 25 09:02:13 2012: gdbus call error: Error: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SessionManager was not provided by any .service files

ERROR: apport (pid 2272) Tue Sep 25 09:02:13 2012: debug: session gdbus call:
ERROR: apport (pid 2272) Tue Sep 25 09:02:13 2012: wrote report /var/crash/_usr_lib_dconf_dconf-service.122.crash

And, in the crash report:

ApportVersion: 2.0.1-0ubuntu13
Dependencies:
 coreutils 8.13-3ubuntu3
 debconf 1.5.42ubuntu1
 dpkg 1.16.1.2ubuntu7
 gcc-4.6-base 4.6.3-1ubuntu5
 libacl1 2.2.51-5ubuntu1
 libattr1 1:2.4.46-5ubuntu1
 libbz2-1.0 1.0.6-1
 libc-bin 2.15-0ubuntu10
 libc6 2.15-0ubuntu10
 libdconf0 0.12.0-0ubuntu1.1
 libffi6 3.0.11~rc1-5
 libgcc1 1:4.6.3-1ubuntu5
 libglib2.0-0 2.32.3-0ubuntu1
 liblzma5 5.1.1alpha+20110809-3
 libpcre3 8.12-4
 libselinux1 2.1.0-4.1ubuntu1
 multiarch-support 2.15-0ubuntu10
 perl-base 5.14.2-6ubuntu2.1
 tar 1.26-4ubuntu1
 tzdata 2012e-0ubuntu0.12.04.1
 xz-utils 5.1.1alpha+20110809-3
 zlib1g 1:1.2.3.4.dfsg-3ubuntu4
Disassembly:
 => 0x7fd279e60fdb <g_logv+475>: lea 0x2a513e(%rip),%rdi # 0x7fd27a106120
    0x7fd279e60fe2 <g_logv+482>: mov %r14d,%esi
    0x7fd279e60fe5 <g_logv+485>: callq 0x7fd279e95980 <g_private_set>
    0x7fd279e60fea <g_logv+490>: nopw 0x0(%rax,%rax,1)
    0x7fd279e60ff0 <g_logv+496>: test %ebx,%ebx
    0x7fd279e60ff2 <g_logv+498>: je 0x7fd279e61010 <g_logv+528>
    0x7fd279e60ff4 <g_logv+500>: sub $0x1,%ebx
    0x7fd279e60ff7 <g_logv+503>: bt %rbx,%r12
    0x7fd279e60ffb <g_logv+507>: jae 0x7fd279e60ff0 <g_logv+496>
    0x7fd279e60ffd <g_logv+509>: cmp $0xffffffff,%ebx
    0x7fd279e61000 <g_logv+512>: jne 0x7fd279e60e78 <g_logv+120>
    0x7fd279e61006 <g_logv+518>: nopw %cs:0x0(%rax,%rax,1)
    0x7fd279e61010 <g_logv+528>: mov 0x458(%rsp),%rdx
    0x7fd279e61018 <g_logv+536>: xor %fs:0x28,%rdx
    0x7fd279e61021 <g_logv+545>: jne 0x7fd279e6111d <g_logv+797>
    0x7fd279e61027 <g_logv+551>: add $0x468,%rsp
InstallationMedia: Ubuntu-Server 10.10 "Maverick Meerkat" - Release amd64 (20101007)
NonfreeKernelModules: nvidia
Package: dconf-service 0.12.0-0ubuntu1.1
PackageArchitecture: amd64
ProcVersionSignature: Ubuntu 3.2.0-31.50-generic 3.2.28
Registers:
 rax 0x0 0
 rbx 0x2 2
 rcx 0x7fd279bee750 140541962413904
 rdx 0x1 1
 rsi 0xffffffff 4294967295
 rdi 0x7fd279bee720 140541962413856
 rbp 0x2 0x2
 rsp 0x7fff5b740280 0x7fff5b740280
 r8 0x0 0
 r9 0x0 0
 r10 0x0 0
 r11 0x246 582
 r12 0x4 4
 r13 0x7fff5b740728 140734727718696
 r14 0x0 0
 r15 0x0 0
 rip 0x7fd279e60fdb 0x7fd279e60fdb <g_logv+475>
 eflags 0x246 [ PF ZF IF ]
 cs 0x33 51
 ss ...

[Luc Bruninx (luc2005)]

Unless it is a coincidence, it seems that the problem no longer occurs when the package gconf-defaults-service is installed.

       sudo apt-get install gconf-defaults-service

Could someone also test this workaround?

[Rick Gatewood (george-gatewood)]

I am no longer having this problem. I confess that I do not recall when it stopped, but I can confirm that I have the latest version of gconf-defaults-service installed.

[Andreas Oberritter (mtdcr)]

I could fix this crash loally with "sudo chown -R lightdm.lightdm /var/lib/lightdm/" (on quantal).

The problem was:

 #0 g_logv (log_domain=0x0, log_level=G_LOG_LEVEL_ERROR, format=<optimized out>, args=args@entry=0x7fff6b957f48) at /build/buildd/glib2.0-2.34.0/./glib/gmessages.c:974
         domain = 0x0
         data = <optimized out>
         depth = <optimized out>
         log_func = 0x7f07b5e924c0 <g_log_default_handler>
         domain_fatal_mask = <optimized out>
         masquerade_fatal = <optimized out>
         test_level = <optimized out>
         was_fatal = <optimized out>
         was_recursion = <optimized out>
         msg = 0x13ee110 "Can not create directory '/var/lib/lightdm/.config/dconf': Permission denied"
         msg_alloc = 0x13ee110 "Can not create directory '/var/lib/lightdm/.config/dconf': Permission denied"
         i = 2

The owner and group of /var/lib/lightdm/.config were messed up.

Searching for "dconf-service crashed with signal 5 in __libc_start_main" on the net shows many bug reports, so maybe this symptom has multiple causes. To find out, install libglib2.0-0-dbg to get a meaningful stacktrace.