My system is Ubuntu 18.04 with Kubuntu desktop running on a Raspberry Pi Model 4, 8 GB.

Until recently all was working fine when I logged in from Windows 10 via Remote Desktop. The current issue is that after Remote Desktop accepts my login credentials, Kubuntu desktop begins to load but hangs after I enter the login credentials at its prompt. The desktop background shows, and the mouse pointer moves; however, there is no response to key or mouse clicks from the system at that point.

I am still able to login to the user account via wifi SSH to the command line.

A strange thing happens to an already open, separate command line SSH terminal after a failed login attempt to Kubuntu desktop via Remote Desktop. The SSH terminal has stopped running BASH properly. A "ls -l" produces no response other than a blank new line and no ubuntu prompt. A CTRL-C is needed to get back to the normal prompt. Switching to sh then correctly runs "ls-l".

Attempts to login in with monitor, keyboard and mouse attached directly to the RPi result in the same issue as with Remote Desktop - system hangs with desktop showing.

I have created another user as a test and can login to that user via Remote Desktop without problems. So, my novice-level conclusion is that I have done something to foul up my original user account.

I really need to get back to being able to use the original user account and appreciate any suggestions as to how to repair things.

Thanks in advance!

Hi!

Even if you can repair your account, you should consider installing a recent version first as Kubuntu 18.04 is EOS since 2021/04!

I do not know how expercienced you are with unixoid systems, so perhaps you just messed your permissions up. As you can login via ssh, check the following:

Code: Select all

find $HOME ! -user $USER -ls  # find files in your home currently owned by another user (root?)
journalctl -b -xep 0..4  # shows errors and warnings since last reboot
less ~/.local/share/xorg/Xorg*log  # (multiple) logfiles containing user errors of your X-Server


If the first command has any output, you have to set permissions back with `sudo chown -R username /home/username`. The second and third command are logfiles you have to read carefully to check errors.

Thanks for the helpful reply!

Well, I am for now stuck with Ubuntu 18.04 because my project uses ROS Melodic version which only works on that. I will in the future upgrade both Ubuntu to 21.04 and ROS to Noetic, but for current project need to stick with what I have.

I ran all three of your suggested tests. I am good on the ownership of files. The "less ~/.local/share/xorg/Xorg*log" test reports no such file.

The "journalctl -b -xep 0..4" test did report errors :
-- Logs begin at Thu 2021-05-27 15:28:51 UTC, end at Thu 2021-08-12 19:51:35 UTC. --
Jul 21 19:41:34 robo2 kernel: kvm [1]: Error, CPU 0 not supported!
Jul 21 19:41:34 robo2 kernel: bcm2708_fb soc:fb: Unable to determine number of FBs. Disabling driver.
Jul 21 19:41:34 robo2 kernel: bcm2708_fb: probe of soc:fb failed with error -2
Jul 21 19:41:34 robo2 kernel: spi-bcm2835 fe204000.spi: could not get clk: -517
Jul 21 19:41:34 robo2 kernel: bcmgenet fd580000.ethernet: failed to get enet clock
Jul 21 19:41:34 robo2 kernel: bcmgenet fd580000.ethernet: failed to get enet-wol clock
Jul 21 19:41:34 robo2 kernel: bcmgenet fd580000.ethernet: failed to get enet-eee clock
Jul 21 19:41:34 robo2 kernel: bcmgenet: Skipping UMAC reset
Jul 21 19:41:34 robo2 kernel: mmc1: queuing unknown CIS tuple 0x80 (2 bytes)
Jul 21 19:41:34 robo2 kernel: mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
Jul 21 19:41:34 robo2 kernel: mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
Jul 21 19:41:34 robo2 kernel: mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
Jul 21 19:41:34 robo2 kernel: mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
Jul 21 19:41:34 robo2 kernel: usb_phy_generic phy: phy supply vcc not found, using dummy regulator
Jul 21 19:41:34 robo2 unknown: Started bpfilter
Jul 21 19:41:38 robo2 kernel: vc_sm_cma: module is from the staging directory, the quality is unknown, you have been warned.
Jul 21 19:41:38 robo2 kernel: bcm2835_mmal_vchiq: module is from the staging directory, the quality is unknown, you have been warned.
Jul 21 19:41:38 robo2 kernel: bcm2835_isp: module is from the staging directory, the quality is unknown, you have been warned.
Jul 21 19:41:38 robo2 kernel: bcm2835_v4l2: module is from the staging directory, the quality is unknown, you have been warned.
Jul 21 19:41:38 robo2 kernel: bcm2835_codec: module is from the staging directory, the quality is unknown, you have been warned.
Jul 21 19:41:38 robo2 kernel: brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43455-sdio for chip BCM4345/6
Jul 21 19:41:38 robo2 kernel: brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43455-sdio for chip BCM4345/6
Jul 21 19:41:38 robo2 kernel: brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM4345/6 wl0: Mar 2 2020 23:30:41 version 7.45.202 (r724630 CY) FWID 01-72f6ece2
Jul 21 19:41:34 robo2 systemd-modules-load[987]: Failed to find module 'ib_iser'
Jul 21 19:41:34 robo2 systemd[1]: systemd-modules-load.service: Failed with result 'exit-code'.
Jul 21 19:41:34 robo2 systemd[1]: Failed to start Load Kernel Modules.
-- Subject: Unit systemd-modules-load.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit systemd-modules-load.service has failed.
--
-- The result is RESULT.
Aug 12 17:25:58 robo2 kernel: new mount options do not match the existing superblock, will be ignored
Aug 12 17:25:58 robo2 udisksd[1840]: failed to load module mdraid: libbd_mdraid.so.2: cannot open shared object file: No such file or directory
Aug 12 17:25:58 robo2 udisksd[1840]: Failed to load the 'mdraid' libblockdev plugin
Aug 12 17:25:59 robo2 kernel: bcmgenet: Skipping UMAC reset
Aug 12 17:25:59 robo2 kernel: brcmfmac: brcmf_cfg80211_set_power_mgmt: power save enabled
Aug 12 17:25:59 robo2 NetworkManager[1830]: <warn> [1628789159.5819] Error: failed to open /run/network/ifstate
Aug 12 17:26:12 robo2 NetworkManager[1830]: <warn> [1628789172.3649] sup-iface[0x1370558,wlan0]: connection disconnected (reason -3)
Aug 12 17:26:18 robo2 systemd[1]: kerneloops.service: Found left-over process 1994 (kerneloops) in control group while starting unit. Ignoring.
Aug 12 17:26:18 robo2 systemd[1]: This usually indicates unclean termination of a previous run, or service implementation deficiencies.
Aug 12 17:26:30 robo2 kernel: [UFW BLOCK] IN=wlan0 OUT= MAC=01:00:5e:00:00:fb:8e:03:94:b6:b4:d1:08:00 SRC=10.0.0.226 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=25679 PRO
Aug 12 17:26:30 robo2 kernel: [UFW BLOCK] IN=wlan0 OUT= MAC=01:00:5e:00:00:fb:f8:8b:37:f5:f5:d3:08:00 SRC=10.0.0.1 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=55232 PROTO
Aug 12 17:26:31 robo2 kernel: [UFW BLOCK] IN=wlan0 OUT= MAC=01:00:5e:00:00:fb:8e:03:94:b6:b4:d1:08:00 SRC=10.0.0.226 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=4523 PROT
lines 1-46/46 (END)


I am going to start researching this output to see if I can figure out what is going on.

Thanks again, and if you have any suggestions on next steps they would be greatly appreciated!

Well, I ended up taking the nuclear option once I found an image saved that had almost all the ROS files. After saving my ROS related source and config stuff, burned a new SD card, and all is well.