我看到有一个问题已经。由于我的问题不完全相同，但据我所知非常相似，所以我也在问这个问题。
基本上在我使用的过程中，即浏览网络或运行随机应用程序。Ubuntu 将我发送到登录窗口，我必须重新登录。我不知道 GDM 是否重新启动或发生其他事情。这是我在 Ubuntu 的稳定版本中遇到的问题。
是否存在我不知道的错误？我该如何调试它？
这是我的~/.xsession_errors文件输出。
/etc/gdm/Xsession: Beginning session setup...
Setting IM through im-switch for locale=en_US.
Start IM through /etc/X11/xinit/xinput.d/all_ALL linked to /etc/X11/xinit/xinput.d/default.
GNOME_KEYRING_CONTROL=/tmp/keyring-CN4XlZ
SSH_AUTH_SOCK=/tmp/keyring-CN4XlZ/ssh
GNOME_KEYRING_CONTROL=/tmp/keyring-CN4XlZ
SSH_AUTH_SOCK=/tmp/keyring-CN4XlZ/ssh
GNOME_KEYRING_CONTROL=/tmp/keyring-CN4XlZ
SSH_AUTH_SOCK=/tmp/keyring-CN4XlZ/ssh
Backend : gconf
Integration : true
Profile : unity
Adding plugins
Initializing core options...done
Window created on XQueryTree, map state isViewable? 0
Window created on XQueryTree, map state isViewable? 0
Window created on XQueryTree, map state isViewable? 0
Window created on XQueryTree, map state isViewable? 0
Window created on XQueryTree, map state isViewable? 0
Initializing bailer options...done
Initializing detection options...done
Initializing composite options...done
Initializing opengl options...done
Initializing decor options...done
Initializing vpswitch options...done
Initializing move options...done
Initializing imgsvg options...done
Initializing expo options...done
Initializing mousepoll options...done
Initializing workarounds options...done
Initializing resize options...done
Initializing gnomecompat options...done
Initializing ezoom options...done
Initializing staticswitcher options...done
Initializing obs options...done
Initializing snap options...done
Initializing scale options...done
Initializing wall options...done
Initializing imgjpeg options...done
Initializing grid options...done
Starting Dropbox...** Message: /home/sagar/.config/desktopnova/pidlock already exists, but process with PID 1911 is not DesktopNova. Daemon will continue starting.
Initializing place options...done
Initializing commands options...done
I/O warning : failed to load external entity "/home/sagar/.compiz/session/10d8191ee2e3827d13130355181434233600000157530036"
Initializing session options...done
** (process:15832): WARNING **: recent-manager-provider.vala:125: Desktop file for audacious2 was not found
(synapse:15840): GtkHotkey-DEBUG: Listener Type: GtkHotkeyX11Listener
** (nm-applet:15829): DEBUG: old state indicates that this was not a disconnect 0
Initializing nautilus-dropbox 0.6.7
Initializing nautilus-gdu extension
Done!
** (<unknown>:15822): DEBUG: Unity accessibility initialization
** (<unknown>:15822): DEBUG: Shows on edge: 1
Screen geometry changed:
Monitor 0(primary)
0x0x1366x768
unity-panel-service: no process found
** (<unknown>:15822): DEBUG: PanelController:: Added Panel for Monitor 0
Initializing unityshell options...done
Initializing unitymtgrabhandles options...done
Starting unity-window-decorator
** (<unknown>:15822): DEBUG: PlaceEntry: Applications
** (<unknown>:15822): DEBUG: PlaceEntry: Commands
** (<unknown>:15822): DEBUG: PlaceEntry: Files & Folders
** (<unknown>:15822): DEBUG: /com/canonical/unity/applicationsplace
** (<unknown>:15822): DEBUG: /com/canonical/unity/filesplace
** (<unknown>:15822): DEBUG: Setting to primary screen rect: x=0 y=0 w=1366 h=768
** (<unknown>:15822): DEBUG: Acquired the name com.canonical.Unity.Launcher on the session bus
** (<unknown>:15822): DEBUG: TrayChild Rejected: dropbox-client-15846 dropbox Dropbox
** (<unknown>:15822): DEBUG: TrayChild Rejected: synapse synapse Synapse
** (<unknown>:15822): DEBUG: TrayChild Rejected: nm-applet nm-applet Nm-applet
** (<unknown>:15822): DEBUG: TrayChild Accepted: gnote gnote Gnote
** (<unknown>:15822): DEBUG: TrayChild Rejected: gst-keyboard-xkb gnome-settings-daemon Gnome-settings-daemon
(gnote:15839): Gdk-CRITICAL **: IA__gdk_window_thaw_toplevel_updates_libgtk_only: assertion `private->update_and_descendants_freeze_count > 0' failed
** (<unknown>:15822): DEBUG: TrayChild Rejected: battery-indicator battery-status Battery-status
** (<unknown>:15822): DEBUG: IndicatorAdded: libapplication.so
** (<unknown>:15822): DEBUG: IndicatorAdded: libsoundmenu.so
** (<unknown>:15822): DEBUG: IndicatorAdded: libmessaging.so
** (<unknown>:15822): DEBUG: IndicatorAdded: libdatetime.so
** (<unknown>:15822): DEBUG: IndicatorAdded: libsession.so
Setting Update "run_key"
Setting Update "run_command_terminal_key"
Setting Update "initiate_output_edge"
Setting Update "launcher_hide_mode"
Setting Update "panel_opacity"
Setting Update "icon_size"
** (gnome-screensaver:16128): WARNING **: screensaver already running in this session
(<unknown>:15822): GLib-GObject-WARNING **: instance of invalid non-instantiatable type `(null)'
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
** (process:15832): DEBUG: zeitgeist-datahub.vala:174: Inserting 1 events
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
** (<unknown>:15822): DEBUG: MaximizeIfBigEnough: window mapped and already maximized, just undecorate
** (<unknown>:15822): DEBUG: MaximizeIfBigEnough: Guake.py window size doesn't fit
** (<unknown>:15822): WARNING **: Unable to fetch children: Method "Children" with signature "" on interface "org.ayatana.bamf.view" doesn't exist
(<unknown>:15822): GLib-GObject-WARNING **: instance of invalid non-instantiatable type `(null)'
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
** (process:15832): DEBUG: zeitgeist-datahub.vala:174: Inserting 1 events
loaded md5.js
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
** (<unknown>:15822): DEBUG: MaximizeIfBigEnough: window mapped and already maximized, just undecorate
(firefox-bin:18524): LIBDBUSMENU-GTK-CRITICAL **: dbusmenu_menuitem_property_set_shortcut: assertion `gtk_accelerator_valid(key, modifier)' failed
** (<unknown>:15822): DEBUG: MaximizeIfBigEnough: Guake.py window size doesn't fit
(<unknown>:15822): GLib-GObject-WARNING **: instance of invalid non-instantiatable type `(null)'
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
** (<unknown>:15822): DEBUG: MaximizeIfBigEnough: Guake.py window size doesn't fit
** (process:15832): DEBUG: zeitgeist-datahub.vala:174: Inserting 1 events
15846 ? 00:00:01 dropbox
22490 ? 00:00:00 unity-dropbox-s
/usr/bin/unity-dropbox-share: line 28: return: can only `return' from a function or sourced script
Error setting attribute: Error setting file metadata: No such file or directory
** (<unknown>:15822): DEBUG: Connected to proxy
(<unknown>:15822): dee-WARNING **: Transaction from com.canonical.Unity.FilesPlace.SectionsModel is in the past. Ignoring transaction.
(<unknown>:15822): dee-WARNING **: Transaction from com.canonical.Unity.FilesPlace.GroupsModel is in the past. Ignoring transaction.
(<unknown>:15822): dee-WARNING **: Transaction from com.canonical.Unity.FilesPlace.GlobalGroupsModel is in the past. Ignoring transaction.
** (<unknown>:15822): DEBUG: Connected to proxy
** (<unknown>:15822): DEBUG: Connected to proxy
(<unknown>:15822): GLib-GIO-CRITICAL **: g_bus_own_name: assertion `g_dbus_is_name (name) && !g_dbus_is_unique_name (name)' failed
(<unknown>:15822): GLib-GIO-CRITICAL **: g_bus_watch_name: assertion `g_dbus_is_name (name)' failed
(<unknown>:15822): GLib-GIO-CRITICAL **: g_bus_own_name: assertion `g_dbus_is_name (name) && !g_dbus_is_unique_name (name)' failed
(<unknown>:15822): GLib-GIO-CRITICAL **: g_bus_watch_name: assertion `g_dbus_is_name (name)' failed
(<unknown>:15822): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion `object_path != NULL && g_variant_is_object_path (object_path)' failed
(<unknown>:15822): GLib-GIO-CRITICAL **: g_dbus_connection_register_object: assertion `object_path != NULL && g_variant_is_object_path (object_path)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
(<unknown>:15822): GLib-GObject-WARNING **: invalid (NULL) pointer instance
(<unknown>:15822): GLib-GObject-CRITICAL **: g_signal_handler_disconnect: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed
** (<unknown>:15822): DEBUG: MaximizeIfBigEnough: Nautilus window size doesn't fit
** (nautilus:15824): WARNING **: Invalid borders specified for theme pixmap:
/home/sagar/.themes/nautilus/null.png,
borders don't fit within the image
** (nautilus:15824): WARNING **: invalid source position for bilinear gradient
** (nautilus:15824): WARNING **: invalid source position for vertical gradient
** (nautilus:15824): WARNING **: invalid source position for horizontal gradient
** (nautilus:15824): WARNING **: Invalid borders specified for theme pixmap:
/home/sagar/.themes/nautilus/null.png,
borders don't fit within the image
** (nautilus:15824): WARNING **: invalid source position for bilinear gradient
** (nautilus:15824): WARNING **: invalid source position for vertical gradient
** (nautilus:15824): WARNING **: invalid source position for horizontal gradient
** (<unknown>:15822): DEBUG: MaximizeIfBigEnough: Guake.py window size doesn't fit
Nautilus-Share-Message: Called "net usershare info" but it failed: 'net usershare' returned error 255: net usershare: cannot open usershare directory /var/lib/samba/usershares. Error No such file or directory
Please ask your system administrator to enable user sharing.
** (nautilus:15824): WARNING **: invalid source position for bilinear gradient
** (nautilus:15824): WARNING **: invalid source position for vertical gradient
** (nautilus:15824): WARNING **: invalid source position for horizontal gradient
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
(nautilus:15824): GLib-GObject-CRITICAL **: g_value_get_object: assertion `G_VALUE_HOLDS_OBJECT (value)' failed
我最近更新了 gnome-sessions。我希望这能解决问题，但是我只能在测试几天后才能确定...将更新情况。
更新：没有进展，更新后问题仍然存在。但似乎比以前少了很多。我正在跟进这个问题，因为有些人建议我重新安装，但现在我面临Compiz 配置更改后 Unity 冻结
答案1
这是一个漏洞。
答案2
您使用的是 Unity 还是 GNOME？尝试另一个。如果不起作用，我建议尝试 Xubuntu（看看它是否是 GNOME）。如果所有这些都失败了，请备份您的主分区或文件夹，并将 /var/cache/apt 复制到另一个文件夹，然后重新安装。使用缓存中的软件包重新安装您的应用程序。
答案3
这可能是视频驱动程序崩溃。您的视频卡是什么？您使用专有驱动程序吗？如果是，请尝试其他版本，或尝试将其完全删除。或者，不幸的是，它可能是许多其他硬件。X 服务器是一个泥腿巨人，最容易受到硬件故障的影响。检查您的内存（memtest86）、硬盘（fsck、smart）、温度（lm-sensors）。尝试关闭所有不必要的硬件和软件。例如，当 EiskalDC++ 尝试索引 100Gb 文件时，我曾看到 X 服务器崩溃。您读过日志、dmesg 吗？有什么可疑的吗？PS 关闭 compiz。它在 ubuntu 中默认启用。
答案4
尝试（在终端中，无需 SUDO）：
unity --reset
然后不要再碰 CCSM（Compiz 设置）。我不知道这对你的情况是否真的有帮助，但我也遇到了同样的情况，目前正在测试崩溃是否仍然发生。