Bug#786390: gnome: Gnome fails opening a session

[titi]

Package: gdm3
Version: 3.14.1-7
Severity: important
File: gnome

Dear Maintainer,

A month ago, I upgraded wheezy to jessie when it became stable. Since
then, when opening  a session, Gnome often (more than half of the time) fails.
It tries to open the session but after 1-2 seconds go back to login
screen. This happens with both sessions already opened (using the
switching user function) and all session closed.

Restarting gdm3 (/etc/init.d/gdm3 restart) and re-attempting to login
works but the next attempt 1 hour later will need gdm3 to be restarted.

-- System Information:
Debian Release: 8.0
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages gdm3 depends on:
ii  accountsservice                              0.6.37-3+b1
ii  adduser                                      3.113+nmu3
ii  dconf-cli                                    0.22.0-1
ii  dconf-gsettings-backend                      0.22.0-1
ii  debconf [debconf-2.0]                        1.5.56
ii  gir1.2-gdm3                                  3.14.1-7
ii  gnome-session [x-session-manager]            3.14.0-2
ii  gnome-session-bin                            3.14.0-2
ii  gnome-session-flashback [x-session-manager]  3.8.1-7
ii  gnome-settings-daemon                        3.14.2-3
ii  gnome-shell                                  3.14.2-3+b1
ii  gnome-terminal [x-terminal-emulator]         3.14.1-1
ii  gsettings-desktop-schemas                    3.14.1-1
ii  libaccountsservice0                          0.6.37-3+b1
ii  libaudit1                                    1:2.4-1+b1
ii  libc6                                        2.19-18
ii  libcanberra-gtk3-0                           0.30-2.1
ii  libcanberra0                                 0.30-2.1
ii  libgdk-pixbuf2.0-0                           2.31.1-2+b1
ii  libgdm1                                      3.14.1-7
ii  libglib2.0-0                                 2.42.1-1
ii  libglib2.0-bin                               2.42.1-1
ii  libgtk-3-0                                   3.14.5-1
ii  libpam-modules                               1.1.8-3.1
ii  libpam-runtime                               1.1.8-3.1
ii  libpam-systemd                               215-17
ii  libpam0g                                     1.1.8-3.1
ii  librsvg2-common                              2.40.5-1
ii  libselinux1                                  2.3-2
ii  libsystemd0                                  215-17
ii  libwrap0                                     7.6.q-25
ii  libx11-6                                     2:1.6.2-3
ii  libxau6                                      1:1.0.8-1
ii  libxdmcp6                                    1:1.1.1-1+b1
ii  libxrandr2                                   2:1.4.2-1+b1
ii  lsb-base                                     4.1+Debian13+nmu1
ii  metacity [x-window-manager]                  1:3.14.3-1
ii  mutter [x-window-manager]                    3.14.2-1
ii  policykit-1                                  0.105-8
ii  ucf                                          3.0030
ii  x11-common                                   1:7.7+7
ii  x11-xserver-utils                            7.7+3+b1
ii  xterm [x-terminal-emulator]                  312-2

Versions of packages gdm3 recommends:
ii  at-spi2-core               2.14.0-1
ii  desktop-base               8.0.2
ii  gnome-icon-theme           3.12.0-1
ii  gnome-icon-theme-symbolic  3.12.0-1
ii  x11-xkb-utils              7.7+1
ii  xserver-xephyr             2:1.16.4-1
ii  xserver-xorg               1:7.7+7
ii  zenity                     3.14.0-1

Versions of packages gdm3 suggests:
pn  gnome-orca            <none>
ii  libpam-gnome-keyring  3.14.0-1+b1

-- Configuration Files:
/etc/gdm3/greeter.gsettings c174f4b4052874d1918d18ccadb6a027 [Errno 2] Aucun fichier ou dossier de ce type: u'/etc/gdm3/greeter.gsettings c174f4b4052874d1918d18ccadb6a027'

-- debconf information:
* shared/default-x-display-manager: gdm3
  gdm3/daemon_name: /usr/sbin/gdm3