Restart in Kubuntu won't work

[Qqmike]

Suddenly, past couple days, on my PC, with K 22.04, K > Restart won't work:
The screen freezes at the K screen with Kubuntu pulsing, but doesn't go any further.
Pressing the Restart button on the PC fixes it, and the PC reboots correctly back into Kubuntu.

Ideas on what's going on / how to fix it?

[die.boer]

It sounds like a shutdown/reboot process hanging near the very end, rather than a problem with GRUB or the normal boot process.
can you try

sudo reboot

and see if it still hangs ?
if it does and you have to press the button on PC to restart , then right after PC starts ,run

journalctl -b -1 -e

and post the last 30-50 lines here

[Qqmike]

It DID hang, btw, and I pressed the PC's restart button.

journalctl -b -1 -e
Sep 05 12:31:15 mike-System-Product-Name anacron[14759]: Anacron 2.3 started on 2026-09-05
Sep 05 12:31:15 mike-System-Product-Name anacron[14759]: Normal exit (0 jobs run)
Sep 05 12:32:10 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:32:10 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:33:34 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:33:34 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:34:11 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:34:11 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:35:03 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:35:03 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:36:12 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:36:12 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:36:20 mike-System-Product-Name cups.cups-browsed[1456]: + true
Sep 05 12:36:20 mike-System-Product-Name cups.cups-browsed[1456]: + sleep 3600
Sep 05 12:37:40 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:37:40 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:38:12 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:38:12 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:39:13 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:39:13 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:42:13 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:42:13 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:44:05 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:44:05 mike-System-Product-Name rtkit-daemon[1487]: Supervising 7 threads of 4 processes of 1 users.
Sep 05 12:45:29 mike-System-Product-Name systemd[1598]: Started Konsole - Terminal.
Sep 05 12:45:43 mike-System-Product-Name sudo[15278]: pam_unix(sudo:auth): authentication failure; logname=mike uid=1000 euid=0 tty>
Sep 05 12:45:54 mike-System-Product-Name sudo[15278]: mike : TTY=pts/1 ; PWD=/home/mike ; USER=root ; COMMAND=/usr/sbin/reboot
Sep 05 12:45:54 mike-System-Product-Name sudo[15278]: pam_unix(sudo:session): session opened for user root(uid=0) by mike(uid=1000)
lines 1063-1090/1090 (END)

Note: "authentication failure": that was me -- I typed my PW wrong, tried again and got it right

[die.boer]

nothing looks suspicious there
can you post output of

journalctl -b -1 -k -p warning

[Qqmike]

journalctl -b -1 -k -p warning
Sep 05 09:36:18 mike-System-Product-Name kernel: x86/cpu: VMX (outside TXT) disabled by BIOS
Sep 05 09:36:18 mike-System-Product-Name kernel: x86/cpu: SGX disabled by BIOS.
Sep 05 09:36:18 mike-System-Product-Name kernel: MMIO Stale Data CPU bug present and SMT on, data leak possible. See https://www.ke>
Sep 05 09:36:18 mike-System-Product-Name kernel: #7 #8 #9 #10 #11
Sep 05 09:36:18 mike-System-Product-Name kernel: ENERGY_PERF_BIAS: Set to 'normal', was 'performance'
Sep 05 09:36:18 mike-System-Product-Name kernel: device-mapper: core: CONFIG_IMA_DISABLE_HTABLE is disabled. Duplicate IMA measurem>
Sep 05 09:36:18 mike-System-Product-Name kernel: ata1.00: supports DRM functions and may not be fully accessible
Sep 05 09:36:18 mike-System-Product-Name kernel: ata1.00: supports DRM functions and may not be fully accessible
Sep 05 09:36:18 mike-System-Product-Name systemd[1]: Configuration file /run/systemd/system/netplan-ovs-cleanup.service is marked w>
Sep 05 09:36:18 mike-System-Product-Name systemd[1]: /lib/systemd/system/snapd.service:23: Unknown key name 'RestartMode' in sectio>
Sep 05 09:36:18 mike-System-Product-Name kernel: snd_hda_codec_hdmi hdaudioC0D2: Monitor plugged-in, Failed to power up codec ret=[>
Sep 05 09:36:19 mike-System-Product-Name kernel: kauditd_printk_skb: 36 callbacks suppressed
Sep 05 09:36:38 mike-System-Product-Name kernel: kauditd_printk_skb: 30 callbacks suppressed
Sep 05 09:36:49 mike-System-Product-Name kernel: kauditd_printk_skb: 12 callbacks suppressed
Sep 05 09:36:51 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:36:53 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:36:56 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:36:58 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:01 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:03 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:06 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:08 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:11 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:13 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:16 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:18 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:21 mike-System-Product-Name kernel: usb 1-1.3: usbfs: interface 1 claimed by usbfs while 'ipp-usb' sets config #1
Sep 05 09:37:23 mike-System-Product-Name kernel: usb 1-1.

[die.boer]

ok , and this 1 please ...

journalctl -b -1 --since "12:45:50" --until "12:46:30"

[Qqmike]

journalctl -b -1 --since "12:45:50" --until "12:46:30"
Sep 05 12:45:54 mike-System-Product-Name sudo[15278]: mike : TTY=pts/1 ; PWD=/home/mike ; USER=root ; COMMAND=/usr/sbin/reboot
Sep 05 12:45:54 mike-System-Product-Name sudo[15278]: pam_unix(sudo:session): session opened for user root(uid=0) by mike(uid=1000)

[Qqmike]

Hmmm ... last two restarts: No problem! I.e., it restarted normally.