大家好，我在WSL2的Ubuntu 22.04.1上尝试使用LightDM，但一直启动失败。我已经试过重新安装LightDM和Polkit了，从日志来看问题似乎和DBus的权限有关。我的桌面环境是GNOME。

我执行了启动命令：

sudo service lightdm start

得到的完整输出日志如下：

* Starting X display manager lightdm                                                                                   [+0.00s] DEBUG: Logging to /var/log/lightdm/lightdm.log

[+0.00s] DEBUG: Starting Light Display Manager 1.30.0, UID=0 PID=4836

[+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d

[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-disable-guest.conf

[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-disable-log-backup.conf

[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-greeter-wrapper.conf

[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-guest-wrapper.conf

[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf

[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-unity-greeter.conf

[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-xserver-command.conf

[+0.00s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d

[+0.00s] DEBUG: Loading configuration dirs from /etc/xdg/lightdm/lightdm.conf.d

[+0.00s] DEBUG: Loading configuration from /etc/lightdm/lightdm.conf

[+0.00s] DEBUG: Registered seat module local

[+0.00s] DEBUG: Registered seat module xremote

[+0.00s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager

[+0.00s] DEBUG: _g_io_module_get_default: Found default implementation local (GLocalVfs) for ?gio-vfs?

[+0.01s] WARNING: Failed to get list of logind seats: GDBus.Error:org.freedesktop.DBus.Error.Spawn.ExecFailed: Failed to execute program org.freedesktop.login1: Permission denied

[+0.01s] DEBUG: Adding default seat

[+0.01s] DEBUG: Seat seat0: Loading properties from config section Seat:*

[+0.01s] DEBUG: Seat seat0: Starting

[+0.01s] DEBUG: Seat seat0: Creating greeter session

[+0.01s] DEBUG: Seat seat0: Creating display server of type x

[+0.01s] DEBUG: Using VT 7

[+0.01s] DEBUG: Seat seat0: Starting local X display on VT 7

[+0.01s] DEBUG: XServer 0: Logging to /var/log/lightdm/x-0.log

[+0.01s] DEBUG: XServer 0: Writing X server authority to /var/run/lightdm/root/:0

[+0.01s] DEBUG: XServer 0: Launching X Server

[+0.01s] DEBUG: Launching process 4844: /bin/X -core :0 -seat seat0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch

[+0.01s] DEBUG: XServer 0: Waiting for ready signal from X server :0

[+0.01s] DEBUG: Acquired bus name org.freedesktop.DisplayManager

[+0.01s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat0

[+0.01s] WARNING: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.Spawn.ExecFailed: Failed to execute program org.freedesktop.Accounts: Permission denied

[+0.01s] DEBUG: Loading user config from /etc/lightdm/users.conf

[+0.01s] WARNING: Failed to read password database: No such file or directory

[+0.01s] DEBUG: User ding added

[+0.03s] DEBUG: Process 4844 terminated with signal 6

[+0.03s] DEBUG: XServer 0: X server stopped

[+0.03s] DEBUG: Releasing VT 7

[+0.03s] DEBUG: XServer 0: Removing X server authority /var/run/lightdm/root/:0

[+0.03s] DEBUG: Seat seat0: Display server stopped

[+0.03s] DEBUG: Seat seat0: Stopping session

[+0.03s] DEBUG: Seat seat0: Session stopped

[+0.03s] DEBUG: Seat seat0: Stopping display server, no sessions require it

[+0.03s] DEBUG: Seat seat0: Stopping; greeter display server failed to start

[+0.03s] DEBUG: Seat seat0: Stopping

[+0.03s] DEBUG: Seat seat0: Stopped

[+0.03s] DEBUG: Required seat has stopped

[+0.03s] DEBUG: Stopping display manager

[+0.03s] DEBUG: Display manager stopped

[+0.03s] DEBUG: Stopping daemon

[+0.03s] DEBUG: Exiting with return value 1

日志里几个关键的错误提示：

• Failed to execute program org.freedesktop.login1: Permission denied
• Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.Spawn.ExecFailed: Failed to execute program org.freedesktop.Accounts: Permission denied
• X服务器进程最终以信号6终止

有没有朋友遇到过类似的问题？或者能给我一些排查方向吗？非常感谢！

备注：内容来源于stack exchange，提问作者W.Ding