（13.04）lightdm崩溃 – 黑屏闪烁光标

我在我的电脑上使用了Ubuntu的13.04 x64版本，至少它应该可行。 但突然间lightdm在启动过程中崩溃，即使我在切换到另一个tty后尝试从终​​端手动启动它。

我不知道是什么原因导致这些问题，因为我甚至没有为我的nvidia卡安装任何图形驱动程序（因为我多年来就知道这些问题并且没有安装任何问题就跳过了这些问题）。

它在新安装和更新后的几天内运行良好，但现在它不应该是它应该的。

切换到gdm确实解决了使用gui登录到我的计算机的问题，但是这个lightdm应该可以工作我猜…

这些日志对我来说并没什么帮助，但也许有人知道是什么了？

lightdm.log [+0.00s] DEBUG: Logging to /var/log/lightdm/lightdm.log [+0.00s] DEBUG: Starting Light Display Manager 1.6.0, UID=0 PID=7369 [+0.00s] DEBUG: Loaded configuration from /etc/lightdm/lightdm.conf [+0.00s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager [+0.00s] DEBUG: Registered seat module xlocal [+0.00s] DEBUG: Registered seat module xremote [+0.00s] DEBUG: Adding default seat [+0.00s] DEBUG: Starting seat [+0.00s] DEBUG: Starting new display for greeter [+0.00s] DEBUG: Starting local X display [+0.00s] DEBUG: Using VT 7 [+0.00s] DEBUG: Activating VT 7 [+0.01s] DEBUG: Logging to /var/log/lightdm/x-1.log [+0.01s] DEBUG: Writing X server authority to /var/run/lightdm/root/:1 [+0.01s] DEBUG: Launching X Server [+0.01s] DEBUG: Launching process 7376: /usr/bin/X :1 -core -auth /var/run/lightdm/root/:1 -nolisten tcp vt7 -novtswitch [+0.01s] DEBUG: Waiting for ready signal from X server :1 [+0.01s] DEBUG: Acquired bus name org.freedesktop.DisplayManager [+0.01s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat0 [+0.61s] DEBUG: Got signal 10 from process 7376 [+0.61s] DEBUG: Got signal from X server :1 [+0.61s] DEBUG: Connecting to XServer :1 [+0.61s] DEBUG: Starting greeter [+0.62s] DEBUG: Started session 7385 with service 'lightdm-greeter', username 'lightdm' [+0.64s] DEBUG: Session 7385 authentication complete with return value 0: Success [+0.64s] DEBUG: Greeter authorized [+0.64s] DEBUG: Logging to /var/log/lightdm/x-1-greeter.log [+0.64s] DEBUG: Session 7385 running command /usr/lib/lightdm/lightdm-greeter-session /usr/sbin/unity-greeter [+0.68s] DEBUG: Greeter closed communication channel [+0.68s] DEBUG: Session 7385 exited with return value 1 [+0.68s] DEBUG: Greeter quit [+0.68s] DEBUG: Failed to start greeter [+0.68s] DEBUG: Stopping display [+0.68s] DEBUG: Sending signal 15 to process 7376 [+0.82s] DEBUG: Process 7376 exited with return value 0 [+0.82s] DEBUG: X server stopped [+0.82s] DEBUG: Removing X server authority /var/run/lightdm/root/:1 [+0.82s] DEBUG: Releasing VT 7 [+0.82s] DEBUG: Display server stopped [+0.82s] DEBUG: Stopping seat, failed to start a display [+0.82s] DEBUG: Stopping seat [+0.82s] DEBUG: Seat stopped [+0.82s] DEBUG: Required seat has stopped [+0.82s] DEBUG: Stopping display manager [+0.82s] DEBUG: Display manager stopped [+0.82s] DEBUG: Stopping daemon [+0.82s] DEBUG: Exiting with return value 1 --- x-0-greeter.log Error writing X authority: Failed to write X authority /var/lib/lightdm/.Xauthority: Success --- x-1-greeter.log Error writing X authority: Failed to write X authority /var/lib/lightdm/.Xauthority: Success /var/log/lightdm/x-1-greeter.log (END) --- x0.log X.Org X Server 1.13.3 Release Date: 2013-03-07 X Protocol Version 11, Revision 0 Build Operating System: Linux 3.2.0-37-generic x86_64 Ubuntu Current Operating System: Linux stefan-dev 3.8.0-30-generic #44-Ubuntu SMP Thu Aug 22 20:52:24 UTC 2013 x86_64 Kernel command line: BOOT_IMAGE=/boot/vmlinuz-3.8.0-30-generic root=UUID=6e9c6967-a55f-49b8-b690-7257b359ae8d ro quiet splash vt.handoff=7 Build Date: 17 April 2013 10:43:13PM xorg-server 2:1.13.3-0ubuntu6 (For technical support please see http://www.ubuntu.com/support) Current version of pixman: 0.28.2 Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. (==) Log file: "/var/log/Xorg.0.log", Time: Tue Sep 17 18:27:30 2013 (==) Using system config directory "/usr/share/X11/xorg.conf.d" Initializing built-in extension Generic Event Extension Initializing built-in extension SHAPE Initializing built-in extension MIT-SHM Initializing built-in extension XInputExtension Initializing built-in extension XTEST Initializing built-in extension BIG-REQUESTS Initializing built-in extension SYNC Initializing built-in extension XKEYBOARD Initializing built-in extension XC-MISC Initializing built-in extension SECURITY Initializing built-in extension XINERAMA Initializing built-in extension XFIXES Initializing built-in extension RENDER Initializing built-in extension RANDR Initializing built-in extension COMPOSITE Initializing built-in extension DAMAGE Initializing built-in extension MIT-SCREEN-SAVER Initializing built-in extension DOUBLE-BUFFER Initializing built-in extension RECORD Initializing built-in extension DPMS Initializing built-in extension X-Resource Initializing built-in extension XVideo Initializing built-in extension XVideo-MotionCompensation Initializing built-in extension SELinux Initializing built-in extension XFree86-VidModeExtension Initializing built-in extension XFree86-DGA Initializing built-in extension XFree86-DRI Initializing built-in extension DRI2 Loading extension GLX resize called 1680 1050 Server terminated successfully (0). Closing log file. 

Answer 1

我花了两天时间。 最终解决方案

1. sudo dpkg-reconfigure gdm #select gdm
2. sudo apt-get remove lightdm* --purge
3. sudo reboot
4. sudo apt-get install lightdm*
5. sudo dpkg-reconfigure gdm #select lightdm

Answer 2

上周应用了当前的lightdm补丁后，我开始遇到这个问题。 由于缺少对/var/lib/lightdm/.Xauthority的访问权限，greeter将无法启动，结果是一个低图形模式错误，只能通过删除/var/lib/lightdm/.Xauthority来解析一个会话。 这个问题似乎是由这个新的补丁引起的，它为.Xauthority文件提供了更严格的权限（ 600而不是664 ）。 请参阅以下内容：

lightdm（1.6.0-0ubuntu3.1）raring-security; 急=低

• 安全更新：.Xauthority文件的权限错误（LP：＃1175023）
  • debian / patches / 07_xauthority_perms.patch：在src / xauthority.c中使用g_open而不是g_file_set_contents。
  • debian / patches / 08_xauthority_fix_perms.patch：修复src / xauthority.c中先前版本遗留的不正确权限。
  • CVE-2013-4331

上面建议的修复似乎工作了大约半小时，直到旧的行为返回，另外的问题是陈旧的.Xauthority文件在用户主目录中留下600权限，导致图形登录循环。

为了解决这个问题，我为xfce-session-logout （我使用XFCE）创建了一个包装器脚本，它从用户主目录和/var/lib/lightdm删除了.Xauthority 。 由于此脚本必须使用sudo来承担删除/var/lib/lightdm/.Xauthority的正确权限，因此尽管它有效，但这并不理想。 使用gdm也可以避免这个问题。 我的情况也很复杂，可能是因为我通过控制台和xdmcp访问本地系统。

为了解决上面补丁中的安全问题，Ubuntu需要修补任何其他程序（例如，接待者）需要访问.Xauthority因为目前通过修复安全问题，他们已经有效地破坏了lightdm 。 那不是很好。

Answer 3

我在Debian Sid上遇到了同样的问题，发现删除.Xauthority文件可以解决问题，虽然不是一个非常可靠的解决方案，因为每次重新启动时我都必须这样做，这是一种解决方法，可以让我回到我的GUI。

• 将文件/var/lib/lightdm/.Xauthority重命名为/var/lib/lightdm/.Xauthority-BAK with

   sudo mv /var/lib/lightdm/.Xauthority /var/lib/lightdm/.Xauthority-BAK 

• 用。重启lightdm服务

   sudo service lightdm stop sudo service lightdm start 

Answer 4

Lubuntu 15.x：
在lightdm-greeter blackscreen，我切换到虚拟终端（ Alt 2 ），登录，然后找到了lightdm-greeter的pid， top -b -n 1 | grep 'lightdm' top -b -n 1 | grep 'lightdm' ，然后我尝试了sudo kill -s SIGHUP [pid] ，然后再次使用top来查看是否仍然在运行，然后尝试了sudo kill -s SIGTERM并再次使用top并且greeter没有运行。 然后我切换回图形会话/登录。 它有一条消息表明会话被锁定，我将被重定向到登录。 我等了大概7秒钟， lightdm-greeter出现了。 我能够登录。 GUI会话完好无损。