[FAILED] Failed to start: Light Display Manager

[Boone777]

Hello ! I’m new to Manjaro but been using Linux for 2 years now distro hoping.
It’s a new installation XFCE Manjaro 21.1.2.
There is a lot of info and posts on this bug but nothing seems to work for me.

I can load the desktop no problem using this command after entering tty:
sudo systemctl restart lightdm

So far I have tried with no success:

sudo chown root:lightdm /var/lib/lightdm-data
sudo mkinitcpio -P and sudo update-grub
logind-check-graphical=true
Deleting the /etc/X11/xorg.conf file then rebooting
pacman -S lightdm-gtk-greeter
pacman -S lightdm-gtk-greeter-settings
systemctl enable lightdm
systemctl reboot
pacman -S xorg

I have tried a few things from wiki archlinuxorg/title/LightDM#Troubleshooting

Also before I try changing video drivers, wich I suspect may be the culprit maybe someone can solve my problem, my computer has a tendency to not like Manjaro for some reason, for exemple KDE Manjaro freezes upon desktop splash screen.

systemctl status lightdm:

● lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: active (running) since Sun 2021-09-12 09:00:32 EDT; 4h 27min ago
       Docs: man:lightdm(1)
   Main PID: 1134 (lightdm)
      Tasks: 6 (limit: 19034)
     Memory: 109.6M
        CPU: 11min 54.032s
     CGroup: /system.slice/lightdm.service
             ├─1134 /usr/bin/lightdm
             └─1459 /usr/lib/Xorg :0 -seat seat0 -auth /run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch

Sep 12 09:00:34 man lightdm[1146]: pam_unix(lightdm-autologin:session): session opened for user man(uid=1000) by (uid=0)
Sep 12 09:00:34 man lightdm[1146]: pam_env(lightdm-autologin:session): deprecated reading of user environment enabled
Sep 12 09:00:34 man lightdm[1146]: gkr-pam: gnome-keyring-daemon started properly
Sep 12 09:00:44 man lightdm[1465]: pam_unix(lightdm-greeter:session): session opened for user lightdm(uid=967) by (uid=0)
Sep 12 09:00:52 man lightdm[1521]: gkr-pam: unable to locate daemon control file
Sep 12 09:00:52 man lightdm[1521]: gkr-pam: stashed password to try later in open session
Sep 12 09:00:52 man lightdm[1521]: pam_systemd_home(lightdm:account): systemd-homed is not available: Unit dbus-org.freedesktop.home1.service not found.
Sep 12 09:00:52 man lightdm[1521]: pam_unix(lightdm:session): session opened for user man(uid=1000) by (uid=0)
Sep 12 09:00:52 man lightdm[1521]: pam_env(lightdm:session): deprecated reading of user environment enabled
Sep 12 09:00:52 man lightdm[1521]: gkr-pam: gnome-keyring-daemon started properly and unlocked keyring

lightdm --test-mode --debug:

man@man ~]$ lightdm --test-mode --debug
[+0.00s] DEBUG: Logging to /home/man/.cache/lightdm/log/lightdm.log
[+0.00s] DEBUG: Starting Light Display Manager 1.30.0, UID=1000 PID=4719
[+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /var/lib/snapd/desktop/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /var/lib/flatpak/exports/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /home/man/.local/share/flatpak/exports/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: Running in user mode
[+0.00s] DEBUG: Using Xephyr for X servers
[+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 gvfs (GDaemonVfs) for ?gio-vfs?
[+0.01s] DEBUG: Monitoring logind for seats
[+0.01s] DEBUG: New seat added from logind: seat0
[+0.01s] DEBUG: Seat seat0: Loading properties from config section Seat:*
[+0.01s] DEBUG: Seat seat0 has property CanMultiSession=no
[+0.01s] DEBUG: Seat seat0: Starting
[+0.01s] DEBUG: Seat seat0: Creating user session
[+0.01s] DEBUG: Loading users from org.freedesktop.Accounts
[+0.01s] DEBUG: Seat seat0: Creating display server of type x
[+0.01s] DEBUG: Could not run plymouth --ping: Failed to execute child process ?plymouth? (No such file or directory)
[+0.01s] DEBUG: Seat seat0: Starting local X display
[+0.01s] DEBUG: XServer 1: Logging to /home/man/.cache/lightdm/log/x-1.log
[+0.01s] DEBUG: XServer 1: Writing X server authority to /run/lightdm/root/:1
[+0.01s] WARNING: Error reading existing Xauthority: Failed to open file ?/run/lightdm/root/:1?: Permission denied
[+0.01s] WARNING: XServer 1: Failed to write authority: Failed to open X authority /run/lightdm/root/:1: Permission denied
[+0.01s] DEBUG: XServer 1: Launching X Server
[+0.01s] DEBUG: Launching process 4724: /usr/bin/Xephyr :1 -seat seat0 -auth /run/lightdm/root/:1 -nolisten tcp
[+0.01s] DEBUG: XServer 1: 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
[+0.01s] WARNING: Could not enumerate user data directory /var/lib/lightdm-data: Error opening directory '/var/lib/lightdm-data': Permission denied
[+0.19s] DEBUG: Got signal 10 from process 4724
[+0.19s] DEBUG: XServer 1: Got signal from X server :1
[+0.19s] DEBUG: XServer 1: Connecting to XServer :1
[+0.19s] DEBUG: Seat seat0: Display server ready, starting session authentication
[+0.19s] DEBUG: Session: Not setting XDG_VTNR
[+0.19s] DEBUG: Session pid=4726: Started with service 'lightdm-autologin', username 'man'
[+0.23s] DEBUG: Session pid=4726: Authentication complete with return value 0: Success
[+0.23s] DEBUG: Seat seat0: Session authenticated, running command
[+0.23s] DEBUG: Registering session with bus path /org/freedesktop/DisplayManager/Session0
[+0.23s] DEBUG: Session pid=4726: Not setting XDG_VTNR
[+0.23s] DEBUG: Session pid=4726: Running command /etc/lightdm/Xsession startxfce4
[+0.23s] DEBUG: Creating shared data directory /var/lib/lightdm-data/man
[+0.23s] WARNING: Could not create user data directory /var/lib/lightdm-data/man: Error creating directory /var/lib/lightdm-data/man: Permission denied
[+0.23s] DEBUG: Session pid=4726: Logging to .xsession-errors

** (process:4726): WARNING **: 13:28:33.299: Failed to open CK session: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.ConsoleKit was not provided by any .service files
Failed to write utmpx: Permission denied
Error writing audit message: Operation not permitted
Failed to write utmpx: Permission denied
Error writing audit message: Operation not permitted
[+0.64s] DEBUG: Session pid=4726: Exited with return value 1
[+0.64s] DEBUG: Seat seat0: Session stopped
[+0.64s] DEBUG: Seat seat0: Stopping display server, no sessions require it
[+0.64s] DEBUG: Sending signal 15 to process 4724
[+0.65s] DEBUG: Process 4724 exited with return value 0
[+0.65s] DEBUG: XServer 1: X server stopped
[+0.65s] DEBUG: XServer 1: Removing X server authority /run/lightdm/root/:1
[+0.65s] DEBUG: Seat seat0: Display server stopped
[+0.65s] DEBUG: Seat seat0: Active display server stopped, starting greeter
[+0.65s] DEBUG: Seat seat0: Creating greeter session
[+0.65s] DEBUG: Seat seat0: Creating display server of type x
[+0.65s] DEBUG: Seat seat0: Starting local X display
[+0.65s] DEBUG: XServer 1: Logging to /home/man/.cache/lightdm/log/x-1.log
[+0.65s] DEBUG: XServer 1: Writing X server authority to /run/lightdm/root/:1
[+0.65s] WARNING: Error reading existing Xauthority: Failed to open file ?/run/lightdm/root/:1?: Permission denied
[+0.65s] WARNING: XServer 1: Failed to write authority: Failed to open X authority /run/lightdm/root/:1: Permission denied
[+0.65s] DEBUG: XServer 1: Launching X Server
[+0.65s] DEBUG: Launching process 4795: /usr/bin/Xephyr :1 -seat seat0 -auth /run/lightdm/root/:1 -nolisten tcp
[+0.65s] DEBUG: XServer 1: Waiting for ready signal from X server :1
[+0.83s] DEBUG: Got signal 10 from process 4795
[+0.83s] DEBUG: XServer 1: Got signal from X server :1
[+0.83s] DEBUG: XServer 1: Connecting to XServer :1
[+0.83s] DEBUG: Seat seat0: Display server ready, starting session authentication
[+0.83s] DEBUG: Session: Not setting XDG_VTNR
[+0.83s] DEBUG: Session pid=4798: Started with service 'lightdm-greeter', username 'man'
[+0.84s] DEBUG: Session pid=4798: Authentication complete with return value 0: Success
[+0.84s] DEBUG: Seat seat0: Session authenticated, running command
[+0.84s] DEBUG: Session pid=4798: Not setting XDG_VTNR
[+0.84s] DEBUG: Session pid=4798: Running command /usr/bin/lightdm-gtk-greeter
[+0.84s] DEBUG: Creating shared data directory /var/lib/lightdm-data/man
[+0.84s] WARNING: Could not create user data directory /var/lib/lightdm-data/man: Error creating directory /var/lib/lightdm-data/man: Permission denied
[+0.84s] DEBUG: Session pid=4798: Logging to /home/man/.cache/lightdm/log/seat0-greeter.log
[+0.93s] DEBUG: Greeter connected version=1.30.0 api=1 resettable=false
[+1.06s] DEBUG: Greeter start authentication
[+1.06s] DEBUG: Session: Not setting XDG_VTNR
[+1.06s] DEBUG: Session pid=4815: Started with service 'lightdm', username '(null)'
[+1.07s] DEBUG: Session pid=4815: Got 1 message(s) from PAM
[+1.07s] DEBUG: Prompt greeter with 1 message(s)

[jrichard326]

If you post an inxi output here, you might get better assistance. In any event, please see:

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How to provide good information

Welcome to Manjaro! To allow all of us helpful gurus on this forum TO HELP YOU, we need some basic information about your system. This probably means you described the symptoms of your problem, but now we need some more information to know where the origin of your issue is exactly. Someone else probably linked you to this tutorial, so if you’re reading this in response to a question, please click the link above this text to bring you to the full and unabridged text of the tutorial… …

[Yochanan]

Tip: When pasting terminal output on Discourse forums, one can either…

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I’ve done it for you this time.

[Boone777]

Thank you for your reply I’m on the road and be back to it soon.
Meanwhile my computer is a i7 3770 3,4 16 gig RAM 1050Ti GPU

[Boone777]

Do I need to install this CUDA thing ? It says 4.4 gig in the AUR repo ? seems overkill for just a try at solving this problem.

[Ludo]

Hi there,
I’m also very new to Manjaro, Linux and all these beautiful stuffs. [So my apology in advance if I screw a few things up]
I post my query here since I think (as far as I understand) that I have the exact same problem as the one discussed here. It also happened after an update.

At startup my computer seems to be unable to launch Light Display Manager [so I just have a black screen saying that it failed to start lightdm] and I do not think it is related to the Nvidia drivers since this is not what my computer seems to use for graphical stuffs…

Here is my inxi output (result of inxi --admin --verbosity=7 --filter --no-host --width)

System:
  Kernel: 5.9.16-1-MANJARO x86_64 bits: 64 compiler: gcc v: 10.2.0 
  parameters: BOOT_IMAGE=/boot/vmlinuz-5.9-x86_64 
  root=UUID=bf8c45ea-c4c6-4825-b779-8a20fda850b3 rw quiet udev.log_priority=3 
  Desktop: i3 4.19.1 info: polybar vt: 7 dm: LightDM 1.30.0 
  Distro: Manjaro Linux base: Arch Linux 
Machine:
  Type: Laptop System: LENOVO product: 20RDCTO1WW v: ThinkPad E15 
  serial: <filter> Chassis: type: 10 serial: <filter> 
  Mobo: LENOVO model: 20RDCTO1WW v: SDK0J40709 WIN serial: <filter> 
  UEFI: LENOVO v: R16ET27W (1.13 ) date: 07/28/2020 
Battery:
  ID-1: BAT0 charge: 42.6 Wh (100.0%) condition: 42.6/45.0 Wh (94.8%) 
  volts: 12.3 min: 11.1 model: LGC 5B10W138 type: Li-poly serial: <filter> 
  status: Full cycles: 15 
Memory:
  RAM: total: 15.32 GiB used: 1.81 GiB (11.8%) 
  RAM Report: permissions: Unable to run dmidecode. Root privileges required. 
CPU:
  Info: Quad Core model: Intel Core i5-10210U bits: 64 type: MT MCP 
  arch: Kaby Lake note: check family: 6 model-id: 8E (142) stepping: C (12) 
  microcode: EA cache: L2: 6 MiB bogomips: 33615 
  Speed: 700 MHz min/max: 400/4200 MHz Core speeds (MHz): 1: 700 2: 700 3: 700 
  4: 700 5: 700 6: 700 7: 700 8: 700 
  Flags: 3dnowprefetch abm acpi adx aes aperfmperf apic arat arch_capabilities 
  arch_perfmon art avx avx2 bmi1 bmi2 bts clflush clflushopt cmov constant_tsc 
  cpuid cpuid_fault cx16 cx8 de ds_cpl dtes64 dtherm dts epb ept ept_ad erms 
  est f16c flexpriority flush_l1d fma fpu fsgsbase fxsr ht hwp hwp_act_window 
  hwp_epp hwp_notify ibpb ibrs ibrs_enhanced ida intel_pt invpcid 
  invpcid_single lahf_lm lm mca mce md_clear mmx monitor movbe mpx msr mtrr 
  nonstop_tsc nopl nx pae pat pbe pcid pclmulqdq pdcm pdpe1gb pebs pge pln pni 
  popcnt pse pse36 pts rdrand rdseed rdtscp rep_good sdbg sep smap smep ss 
  ssbd sse sse2 sse4_1 sse4_2 ssse3 stibp syscall tm tm2 tpr_shadow tsc 
  tsc_adjust tsc_deadline_timer vme vmx vnmi vpid x2apic xgetbv1 xsave xsavec 
  xsaveopt xsaves xtopology xtpr 
  Vulnerabilities: Type: itlb_multihit status: KVM: VMX disabled 
  Type: l1tf status: Not affected 
  Type: mds status: Not affected 
  Type: meltdown status: Not affected 
  Type: spec_store_bypass 
  mitigation: Speculative Store Bypass disabled via prctl and seccomp 
  Type: spectre_v1 
  mitigation: usercopy/swapgs barriers and __user pointer sanitization 
  Type: spectre_v2 mitigation: Enhanced IBRS, IBPB: conditional, RSB filling 
  Type: srbds mitigation: TSX disabled 
  Type: tsx_async_abort status: Not affected 
Graphics:
  Device-1: Intel CometLake-U GT2 [UHD Graphics] vendor: Lenovo driver: i915 
  v: kernel bus-ID: 00:02.0 chip-ID: 8086:9b41 class-ID: 0300 
  Device-2: IMC Networks Integrated Camera type: USB driver: uvcvideo 
  bus-ID: 1-8:2 chip-ID: 13d3:5415 class-ID: 0e02 
  Display: x11 server: X.Org 1.20.13 driver: loaded: modesetting 
  alternate: fbdev,vesa display-ID: :0 screens: 1 
  Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 508x285mm (20.0x11.2") 
  s-diag: 582mm (22.9") 
  Monitor-1: eDP-1 res: 1920x1080 hz: 60 dpi: 142 size: 344x194mm (13.5x7.6") 
  diag: 395mm (15.5") 
  OpenGL: renderer: Mesa Intel UHD Graphics (CML GT2) v: 4.6 Mesa 21.2.1 
  direct render: Yes 
Audio:
  Device-1: Intel Comet Lake PCH-LP cAVS vendor: Lenovo driver: snd_hda_intel 
  v: kernel alternate: snd_soc_skl,snd_sof_pci bus-ID: 00:1f.3 
  chip-ID: 8086:02c8 class-ID: 0403 
  Sound Server-1: ALSA v: k5.9.16-1-MANJARO running: yes 
  Sound Server-2: JACK v: 1.9.19 running: no 
  Sound Server-3: PulseAudio v: 15.0 running: yes 
Network:
  Device-1: Intel Comet Lake PCH-LP CNVi WiFi driver: iwlwifi v: kernel 
  port: 3000 bus-ID: 00:14.3 chip-ID: 8086:02f0 class-ID: 0280 
  IF: wlp0s20f3 state: up mac: <filter> 
  IP v4: <filter> type: dynamic noprefixroute scope: global 
  broadcast: <filter> 
  IP v6: <filter> type: dynamic noprefixroute scope: global 
  IP v6: <filter> type: noprefixroute scope: link 
  Device-2: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet 
  vendor: Lenovo driver: r8169 v: kernel port: 2000 bus-ID: 04:00.0 
  chip-ID: 10ec:8168 class-ID: 0200 
  IF: enp4s0 state: down mac: <filter> 
  WAN IP: <filter> 
Bluetooth:
  Device-1: Intel AX201 Bluetooth type: USB driver: btusb v: 0.8 
  bus-ID: 1-10:3 chip-ID: 8087:0026 class-ID: e001 
  Report: rfkill ID: hci0 rfk-id: 2 state: up address: see --recommends 
Logical:
  Message: No logical block device data found. 
RAID:
  Message: No RAID data found. 
Drives:
  Local Storage: total: 1.38 TiB used: 77.4 GiB (5.5%) 
  SMART Message: Required tool smartctl not installed. Check --recommends 
  ID-1: /dev/nvme0n1 maj-min: 259:0 vendor: Toshiba model: KBG40ZNT512G MEMORY 
  size: 476.94 GiB block-size: physical: 512 B logical: 512 B speed: 31.6 Gb/s 
  lanes: 4 type: SSD serial: <filter> rev: 0109AELA temp: 35.9 C scheme: GPT 
  ID-2: /dev/sda maj-min: 8:0 vendor: Seagate model: ST1000LM035-1RK172 
  size: 931.51 GiB block-size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s 
  type: HDD rpm: 5400 serial: <filter> rev: LFM1 scheme: GPT 
  Message: No optical or floppy data found. 
Partition:
  ID-1: / raw-size: 53.21 GiB size: 52.13 GiB (97.96%) used: 41.27 GiB (79.2%) 
  fs: ext4 dev: /dev/nvme0n1p6 maj-min: 259:6 label: N/A 
  uuid: bf8c45ea-c4c6-4825-b779-8a20fda850b3 
  ID-2: /boot/efi raw-size: 512 MiB size: 511 MiB (99.80%) 
  used: 312 KiB (0.1%) fs: vfat dev: /dev/nvme0n1p5 maj-min: 259:5 label: N/A 
  uuid: 227A-B111 
  ID-3: /home raw-size: 488.28 GiB size: 479.62 GiB (98.23%) 
  used: 36.12 GiB (7.5%) fs: ext4 dev: /dev/sda3 maj-min: 8:3 label: N/A 
  uuid: fcd92878-0d5a-4789-b540-f5808f32f438 
Swap:
  Kernel: swappiness: 60 (default) cache-pressure: 100 (default) 
  ID-1: swap-1 type: file size: 8 GiB used: 0 KiB (0.0%) priority: -2 
  file: /swapfile 
Unmounted:
  ID-1: /dev/nvme0n1p1 maj-min: 259:1 size: 260 MiB fs: vfat label: SYSTEM 
  uuid: 3A25-8380 
  ID-2: /dev/nvme0n1p2 maj-min: 259:2 size: 16 MiB fs: <superuser required> 
  label: N/A uuid: N/A 
  ID-3: /dev/nvme0n1p3 maj-min: 259:3 size: 421.98 GiB fs: ntfs label: Windows 
  uuid: 4E8827E98827CE71 
  ID-4: /dev/nvme0n1p4 maj-min: 259:4 size: 1000 MiB fs: ntfs label: WinRE_DRV 
  uuid: D6A8285FA828407B 
  ID-5: /dev/sda1 maj-min: 8:1 size: 128 MiB fs: <superuser required> 
  label: N/A uuid: N/A 
  ID-6: /dev/sda2 maj-min: 8:2 size: 443.1 GiB fs: ntfs label: Data 
  uuid: 06B066A6B0669BC5 
USB:
  Hub-1: 1-0:1 info: Full speed (or root) Hub ports: 12 rev: 2.0 
  speed: 480 Mb/s chip-ID: 1d6b:0002 class-ID: 0900 
  Device-1: 1-8:2 info: IMC Networks Integrated Camera type: Video 
  driver: uvcvideo interfaces: 2 rev: 2.0 speed: 480 Mb/s power: 500mA 
  chip-ID: 13d3:5415 class-ID: 0e02 
  Device-2: 1-10:3 info: Intel AX201 Bluetooth type: Bluetooth driver: btusb 
  interfaces: 2 rev: 2.0 speed: 12 Mb/s power: 100mA chip-ID: 8087:0026 
  class-ID: e001 
  Hub-2: 2-0:1 info: Full speed (or root) Hub ports: 6 rev: 3.1 speed: 10 Gb/s 
  chip-ID: 1d6b:0003 class-ID: 0900 
Sensors:
  System Temperatures: cpu: 46.0 C mobo: 0.0 C 
  Fan Speeds (RPM): cpu: 0 
Info:
  Processes: 216 Uptime: 49m wakeups: 3 Init: systemd v: 248 tool: systemctl 
  Compilers: gcc: 11.1.0 Packages: pacman: 1254 lib: 291 Shell: Bash v: 5.1.8 
  running-in: st inxi: 3.3.06 

the thing is : I can run lightdm manually by launching tty, login in as sudo and typing sudo systemctl start lightdm. After that, lightdm starts and my computer seems to work normally.

If I look for lightdm status after doing all of this, I get as result of systemctl status lightdm :

● lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: active (running) since Thu 2021-09-23 11:10:33 CEST; 46min ago
       Docs: man:lightdm(1)
   Main PID: 29174 (lightdm)
      Tasks: 7 (limit: 18807)
     Memory: 146.7M
        CPU: 1min 18.278s
     CGroup: /system.slice/lightdm.service
             ├─29174 /usr/bin/lightdm
             └─29180 /usr/lib/Xorg :0 -seat seat0 -auth /run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch

Sep 23 11:10:33 thinkpad systemd[1]: Starting Light Display Manager...
Sep 23 11:10:33 thinkpad systemd[1]: Started Light Display Manager.
Sep 23 11:10:34 thinkpad lightdm[29194]: pam_unix(lightdm-greeter:session): session opened for user lightdm(uid=971) by (uid=0)
Sep 23 11:10:38 thinkpad lightdm[30831]: gkr-pam: unable to locate daemon control file
Sep 23 11:10:38 thinkpad lightdm[30831]: gkr-pam: stashed password to try later in open session
Sep 23 11:10:38 thinkpad lightdm[30831]: pam_systemd_home(lightdm:account): systemd-homed is not available: Unit dbus-org.freedesktop.home1.service not found.
Sep 23 11:10:38 thinkpad lightdm[30831]: pam_unix(lightdm:session): session opened for user ludovic(uid=1000) by (uid=0)
Sep 23 11:10:38 thinkpad lightdm[30831]: pam_env(lightdm:session): deprecated reading of user environment enabled
Sep 23 11:10:38 thinkpad lightdm[30831]: gkr-pam: gnome-keyring-daemon started properly and unlocked keyring

also, the lightdm --test-mode output is empty.

BUT, if I do systemctl status lightdm directly at startup in tty, I get

x lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Thu 2021-09-23 12:09:34 CEST; 3min 28s ago
       Docs: man:lightdm(1)
   Process : 2304 ExecStart=/usr/bin/lightdm (code=exited, status=1/FAILURE)
   Main PID: 2304 (code=exited, status=1/FAILURE)
        CPU: 19ms

Sep 23 12:09:34 thinkpad systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 5.
Sep 23 12:09:34 thinkpad systemd[1]: Stopped Light Display Manager.
Sep 23 12:09:34 thinkpad systemd[1]: lightdm.service: Start resquest repeated too quickly.
Sep 23 12:09:34 thinkpad systemd[1]: lightdm.service: Failed with result 'exit-code' .
Sep 23 12:09:34 thinkpad systemd[1]: Failed to start Light Display Manager.

and lightdm --test-mode gives

** (lightdm:14051): WARNING **: 12:12:01.501: Error reading existing Xauthority: Failed to open file ?/run/lightdm/root/:0?: Permission denied
** (lightdm:14051): WARNING **: 12:12:01.503: XServer 0: Failed to write authority: Failed to open X authority /run/lightdm/root/:0: Permission denied
** (lightdm:14051): WARNING **: 12:12:01.503: Could not enumerate user data directory /var/lib/lightdm-data: Error opening directory '/var/lib/lightdm-data': Permission denied

So, even though I’m a 100% newbie and might then be wrong, it looks to me like “everything is OK” (lightdm works, etc)
but something as been changed during the update (in some obscure file) so that lightdm does not have (or thinks it does not have) the permission to access some files.

Does anyone knows where this might come from and/or how to restore the permission ?

Hope this helps the discussion. Thanks in advance to anyone who will help.

[jrichard326]

@Ludo Please update your Kernel to one of the LTS kernels, 5.4 or 5.10 and fully update your system as well, if it is not updated. Kernel 5.9 has been EOL for quite some time.

[Ludo]

Hi, thanks for pointing this out.

I updated my kernel to Manjaro 5.10 and fully updated the system (sudo pacman -Syu) but the error is still the same.

I copy here my new inxi output (mainly the same as before… but beter safe than sory)

System:
  Kernel: 5.10.63-1-MANJARO x86_64 bits: 64 compiler: gcc v: 11.1.0 
  parameters: BOOT_IMAGE=/boot/vmlinuz-5.10-x86_64 
  root=UUID=bf8c45ea-c4c6-4825-b779-8a20fda850b3 rw quiet udev.log_priority=3 
  Desktop: i3 4.19.1 info: polybar vt: 7 dm: LightDM 1.30.0 
  Distro: Manjaro Linux base: Arch Linux 
Machine:
  Type: Laptop System: LENOVO product: 20RDCTO1WW v: ThinkPad E15 
  serial: <filter> Chassis: type: 10 serial: <filter> 
  Mobo: LENOVO model: 20RDCTO1WW v: SDK0J40709 WIN serial: <filter> 
  UEFI: LENOVO v: R16ET27W (1.13 ) date: 07/28/2020 
Battery:
  ID-1: BAT0 charge: 41.3 Wh (96.9%) condition: 42.6/45.0 Wh (94.8%) 
  volts: 12.2 min: 11.1 model: LGC 5B10W138 type: Li-poly serial: <filter> 
  status: Unknown cycles: 15 
Memory:
  RAM: total: 15.32 GiB used: 1.53 GiB (10.0%) 
  RAM Report: permissions: Unable to run dmidecode. Root privileges required. 
CPU:
  Info: Quad Core model: Intel Core i5-10210U bits: 64 type: MT MCP 
  arch: Kaby Lake note: check family: 6 model-id: 8E (142) stepping: C (12) 
  microcode: EA cache: L2: 6 MiB bogomips: 33615 
  Speed: 700 MHz min/max: 400/4200 MHz Core speeds (MHz): 1: 700 2: 700 3: 700 
  4: 700 5: 701 6: 700 7: 700 8: 700 
  Flags: 3dnowprefetch abm acpi adx aes aperfmperf apic arat arch_capabilities 
  arch_perfmon art avx avx2 bmi1 bmi2 bts clflush clflushopt cmov constant_tsc 
  cpuid cpuid_fault cx16 cx8 de ds_cpl dtes64 dtherm dts epb ept ept_ad erms 
  est f16c flexpriority flush_l1d fma fpu fsgsbase fxsr ht hwp hwp_act_window 
  hwp_epp hwp_notify ibpb ibrs ibrs_enhanced ida intel_pt invpcid 
  invpcid_single lahf_lm lm mca mce md_clear mmx monitor movbe mpx msr mtrr 
  nonstop_tsc nopl nx pae pat pbe pcid pclmulqdq pdcm pdpe1gb pebs pge pln pni 
  popcnt pse pse36 pts rdrand rdseed rdtscp rep_good sdbg sep smap smep ss 
  ssbd sse sse2 sse4_1 sse4_2 ssse3 stibp syscall tm tm2 tpr_shadow tsc 
  tsc_adjust tsc_deadline_timer vme vmx vnmi vpid x2apic xgetbv1 xsave xsavec 
  xsaveopt xsaves xtopology xtpr 
  Vulnerabilities: Type: itlb_multihit status: KVM: VMX disabled 
  Type: l1tf status: Not affected 
  Type: mds status: Not affected 
  Type: meltdown status: Not affected 
  Type: spec_store_bypass 
  mitigation: Speculative Store Bypass disabled via prctl and seccomp 
  Type: spectre_v1 
  mitigation: usercopy/swapgs barriers and __user pointer sanitization 
  Type: spectre_v2 mitigation: Enhanced IBRS, IBPB: conditional, RSB filling 
  Type: srbds mitigation: TSX disabled 
  Type: tsx_async_abort status: Not affected 
Graphics:
  Device-1: Intel CometLake-U GT2 [UHD Graphics] vendor: Lenovo driver: i915 
  v: kernel bus-ID: 00:02.0 chip-ID: 8086:9b41 class-ID: 0300 
  Device-2: IMC Networks Integrated Camera type: USB driver: uvcvideo 
  bus-ID: 1-8:2 chip-ID: 13d3:5415 class-ID: 0e02 
  Display: x11 server: X.Org 1.20.13 driver: loaded: modesetting 
  alternate: fbdev,vesa display-ID: :0 screens: 1 
  Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 508x285mm (20.0x11.2") 
  s-diag: 582mm (22.9") 
  Monitor-1: eDP-1 res: 1920x1080 hz: 60 dpi: 142 size: 344x194mm (13.5x7.6") 
  diag: 395mm (15.5") 
  OpenGL: renderer: Mesa Intel UHD Graphics (CML GT2) v: 4.6 Mesa 21.2.1 
  direct render: Yes 
Audio:
  Device-1: Intel Comet Lake PCH-LP cAVS vendor: Lenovo driver: snd_hda_intel 
  v: kernel alternate: snd_soc_skl,snd_sof_pci bus-ID: 00:1f.3 
  chip-ID: 8086:02c8 class-ID: 0403 
  Sound Server-1: ALSA v: k5.10.63-1-MANJARO running: yes 
  Sound Server-2: JACK v: 1.9.19 running: no 
  Sound Server-3: PulseAudio v: 15.0 running: yes 
Network:
  Device-1: Intel Comet Lake PCH-LP CNVi WiFi driver: iwlwifi v: kernel 
  port: 3000 bus-ID: 00:14.3 chip-ID: 8086:02f0 class-ID: 0280 
  IF: wlp0s20f3 state: up mac: <filter> 
  IP v4: <filter> type: dynamic noprefixroute scope: global 
  broadcast: <filter> 
  IP v6: <filter> type: dynamic noprefixroute scope: global 
  IP v6: <filter> type: noprefixroute scope: link 
  Device-2: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet 
  vendor: Lenovo driver: r8169 v: kernel port: 2000 bus-ID: 04:00.0 
  chip-ID: 10ec:8168 class-ID: 0200 
  IF: enp4s0 state: down mac: <filter> 
  WAN IP: <filter> 
Bluetooth:
  Device-1: Intel AX201 Bluetooth type: USB driver: btusb v: 0.8 
  bus-ID: 1-10:3 chip-ID: 8087:0026 class-ID: e001 
  Report: rfkill ID: hci0 rfk-id: 3 state: up address: see --recommends 
Logical:
  Message: No logical block device data found. 
RAID:
  Message: No RAID data found. 
Drives:
  Local Storage: total: 1.38 TiB used: 77.92 GiB (5.5%) 
  SMART Message: Required tool smartctl not installed. Check --recommends 
  ID-1: /dev/nvme0n1 maj-min: 259:0 vendor: Toshiba model: KBG40ZNT512G MEMORY 
  size: 476.94 GiB block-size: physical: 512 B logical: 512 B speed: 31.6 Gb/s 
  lanes: 4 type: SSD serial: <filter> rev: 0109AELA temp: 29.9 C scheme: GPT 
  ID-2: /dev/sda maj-min: 8:0 vendor: Seagate model: ST1000LM035-1RK172 
  size: 931.51 GiB block-size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s 
  type: HDD rpm: 5400 serial: <filter> rev: LFM1 scheme: GPT 
  Message: No optical or floppy data found. 
Partition:
  ID-1: / raw-size: 53.21 GiB size: 52.13 GiB (97.96%) used: 41.77 GiB (80.1%) 
  fs: ext4 dev: /dev/nvme0n1p6 maj-min: 259:6 label: N/A 
  uuid: bf8c45ea-c4c6-4825-b779-8a20fda850b3 
  ID-2: /boot/efi raw-size: 512 MiB size: 511 MiB (99.80%) 
  used: 312 KiB (0.1%) fs: vfat dev: /dev/nvme0n1p5 maj-min: 259:5 label: N/A 
  uuid: 227A-B111 
  ID-3: /home raw-size: 488.28 GiB size: 479.62 GiB (98.23%) 
  used: 36.15 GiB (7.5%) fs: ext4 dev: /dev/sda3 maj-min: 8:3 label: N/A 
  uuid: fcd92878-0d5a-4789-b540-f5808f32f438 
Swap:
  Kernel: swappiness: 60 (default) cache-pressure: 100 (default) 
  ID-1: swap-1 type: file size: 8 GiB used: 0 KiB (0.0%) priority: -2 
  file: /swapfile 
Unmounted:
  ID-1: /dev/nvme0n1p1 maj-min: 259:1 size: 260 MiB fs: vfat label: SYSTEM 
  uuid: 3A25-8380 
  ID-2: /dev/nvme0n1p2 maj-min: 259:2 size: 16 MiB fs: <superuser required> 
  label: N/A uuid: N/A 
  ID-3: /dev/nvme0n1p3 maj-min: 259:3 size: 421.98 GiB fs: ntfs label: Windows 
  uuid: 4E8827E98827CE71 
  ID-4: /dev/nvme0n1p4 maj-min: 259:4 size: 1000 MiB fs: ntfs label: WinRE_DRV 
  uuid: D6A8285FA828407B 
  ID-5: /dev/sda1 maj-min: 8:1 size: 128 MiB fs: <superuser required> 
  label: N/A uuid: N/A 
  ID-6: /dev/sda2 maj-min: 8:2 size: 443.1 GiB fs: ntfs label: Data 
  uuid: 06B066A6B0669BC5 
USB:
  Hub-1: 1-0:1 info: Full speed (or root) Hub ports: 12 rev: 2.0 
  speed: 480 Mb/s chip-ID: 1d6b:0002 class-ID: 0900 
  Device-1: 1-8:2 info: IMC Networks Integrated Camera type: Video 
  driver: uvcvideo interfaces: 2 rev: 2.0 speed: 480 Mb/s power: 500mA 
  chip-ID: 13d3:5415 class-ID: 0e02 
  Device-2: 1-10:3 info: Intel AX201 Bluetooth type: Bluetooth driver: btusb 
  interfaces: 2 rev: 2.0 speed: 12 Mb/s power: 100mA chip-ID: 8087:0026 
  class-ID: e001 
  Hub-2: 2-0:1 info: Full speed (or root) Hub ports: 6 rev: 3.1 speed: 10 Gb/s 
  chip-ID: 1d6b:0003 class-ID: 0900 
Sensors:
  System Temperatures: cpu: 38.0 C mobo: 0.0 C 
  Fan Speeds (RPM): cpu: 0 
Info:
  Processes: 259 Uptime: 1h 37m wakeups: 4 Init: systemd v: 249 
  tool: systemctl Compilers: gcc: 11.1.0 Packages: pacman: 1254 lib: 291 
  Shell: Bash v: 5.1.8 running-in: st inxi: 3.3.06 

The infos provided by lightdm are also still mainly the same :

• after I start lightdm manually, systemctl status lightdm returns

● lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: active (running) since Fri 2021-09-24 12:25:14 CEST; 1h 37min ago
       Docs: man:lightdm(1)
   Main PID: 5905 (lightdm)
      Tasks: 7 (limit: 18800)
     Memory: 157.0M
        CPU: 15.195s
     CGroup: /system.slice/lightdm.service
             ├─5905 /usr/bin/lightdm
             └─5911 /usr/lib/Xorg :0 -seat seat0 -auth /run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch

Sep 24 12:25:14 thinkpad systemd[1]: Starting Light Display Manager...
Sep 24 12:25:14 thinkpad systemd[1]: Started Light Display Manager.
Sep 24 12:25:15 thinkpad lightdm[5922]: pam_unix(lightdm-greeter:session): session opened for user lightdm(uid=971) by (uid=0)
Sep 24 12:25:20 thinkpad lightdm[5981]: gkr-pam: unable to locate daemon control file
Sep 24 12:25:20 thinkpad lightdm[5981]: gkr-pam: stashed password to try later in open session
Sep 24 12:25:20 thinkpad lightdm[5981]: pam_systemd_home(lightdm:account): systemd-homed is not available: Unit dbus-org.freedesktop.home1.service not found.
Sep 24 12:25:20 thinkpad lightdm[5981]: pam_unix(lightdm:session): session opened for user ludovic(uid=1000) by (uid=0)
Sep 24 12:25:20 thinkpad lightdm[5981]: pam_env(lightdm:session): deprecated reading of user environment enabled
Sep 24 12:25:20 thinkpad lightdm[5981]: gkr-pam: gnome-keyring-daemon started properly and unlocked keyring

• and the lightdm --test-mode output is empty.

WHILE

• systemctl status lightdm directly at startup in tty, gives

x lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Fri 2021-09-24 14:04:41 CEST; 42s ago
       Docs: man:lightdm(1)
    Process: 2248 ExecStart=/usr/bin/lightdm (code=exited, status=1/FAILURE)
   Main PID: 2248 (code=exited, status=1/FAILURE)
        CPU: 21ms

Sep 24 14:04:41 thinkpad systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 5.
Sep 24 14:04:41 thinkpad systemd[1]: Stopped Light Display Manager.
Sep 24 14:04:41 thinkpad systemd[1]: lightdm.service: Start request repeated too quickly.
Sep 24 14:04:41 thinkpad systemd[1]: lightdm.service: Failed with result 'exit-code' .
Sep 24 14:04:41 thinkpad systemd[1]: Failed to start Light Display Manager.

• and lightdm --test-mode gives

** (lightdm:10903): WARNING **: 14:06:24.086: Error reading existing Xauthority: Failed to open file ?/run/lightdm/root/:0?: Permission denied
** (lightdm:10903): WARNING **: 14:06:24.088: XServer 0: Failed to write authority: Failed to open X authority /run/lightdm/root/:0: Permission denied
** (lightdm:10903): WARNING **: 14:06:24.089: Could not enumerate user data directory /var/lib/lightdm-data: Error opening directory '/var/lib/lightdm-data': Permission denied

Hope I did not provided too much infos twice if not needed.

Any idea how to remove this error now ?

Thanks in advance !

[jrichard326]

@Ludo

Error reading existing Xauthority: Failed to open file ?/run/lightdm/root/:0?: Permission denied

https://bbs.archlinux.org/viewtopic.php?id=212073

[Ludo]

@jrichard326 : Thanks for the answer !

I read the content of this discussion but, unfortunately, this didn’t help.

What solved the problem in this case (as far as I understood) was to make sure that the session-wrapper=/etc/lightdm/Xsession instruction is uncommented in /etc/lightdm/lightdm.conf but this is the case for me.
I also tried to delete the lightdm-gtk-greeter.conf file and reinstalled the package to get the original file back, as suggested, but this does not change a thing.
(Note : I ignored instructions related to KDE greeter as I’m using GTK)

Any idea ? Am I missing something obvious ?

Thanks in advance !

[dribcot]

I am fairly certain I have exactly the same issue as Boone777 and Ludo.

The lightdm fails to start automatically but can be started manually by breaking into a Terminal and running systemctl restart lightdm.

I also upgraded to kernel 5.10 from 5.9, but no cigar.