Kernel Panic after reboot finishes

Ask Fedora
1

When viewing the reboot sequence by pressing esc
at the end watchdog doesn’t stop, and then the screen goes black, and the Caps Lock key flashes.

2

This is what you see with hardware errors like bad RAM, but can also be caused by firmware bugs, failing PSU, or inadequate cooling. The usual troubleshooting steps:

  1. run the standalone memtest86+ overnight for a couple nights,
  2. make sure you have current Fedora and vendor firmware so you aren’t chasing a solved problem,
  3. check that active cooling components are clean and unobstructed (and maybe renew heatsink compound on older systems) and use one of the many temperature monitoring apps., and
  4. check for similar reports for your model running other linux distros and Windows — sometimes there are known component failures
3

For what it’s worth, watchdog does not stop here either, but I have no issues with reboot.

└─➜ journalctl -g watchdog -b -1 --no-pager                                                                                                                                             ⏱️ 9s 18:55 Mon 29-Jun
Jun 26 16:29:55 lurcher kernel: NMI watchdog: Enabled. Permanently consumes one hw-PMU counter.
Jun 26 16:29:55 lurcher kernel: sp5100_tco: SP5100/SB800 TCO WatchDog Timer Driver
Jun 26 16:29:55 lurcher kernel: sp5100-tco sp5100-tco: Using 0xfeb00000 for watchdog MMIO address
Jun 26 16:30:03 lurcher rtkit-daemon[1297]: Watchdog thread running.
Jun 28 12:16:37 lurcher systemd[1]: Using hardware watchdog /dev/watchdog0: 'SP5100 TCO timer', version 0.
Jun 28 12:16:37 lurcher systemd[1]: Watchdog running with a hardware timeout of 10min.
Jun 28 12:16:37 lurcher kernel: watchdog: watchdog0: watchdog did not stop!
Jun 28 12:16:37 lurcher systemd-shutdown[1]: Using hardware watchdog /dev/watchdog0: 'SP5100 TCO timer', version 0.
Jun 28 12:16:37 lurcher systemd-shutdown[1]: Watchdog running with a hardware timeout of 10min.
4

After installing security updates, the issue was fixed, and now I can reboot without issues.

5

Maybe your hardware is working properly. One of my older and well-used/abused systems has had the blinking caps-lock associated with watchdog not stopping a few times, but usually reboots normally.

6

To be honest George, in these situations, I usually assume some crappy BIOS code in non-enterprise equipment is just crappy BIOS code, and move on.

Much like you, I don’t mind too much if everything works correctly… until I have to get up and kick it to death and back to persuade it to do my bidding once more.

Curse this thinking sand.

7

Im confused on what fixed my issue.
Maybe the kernel upgrade from kernel 7.0.12 to 7.0.14 (EOL)