Comment # 7 on bug 1158241 from Franck Bui

I couldn't find anything interesting in the logs.

So basically journald was stuck when performing IOs (most likely when it was
writing journal into the disk) for too long and wasn't able to send the
keep-alive ping to PID1 in time.

PID1 assumes in this case that something wrong happened to journald and killed
it with SIGABRT.

This might happen when your system is high loaded. One thing that might be
worth noting is that the disk self tests was started pretty before the issue
happened:

> Dec 02 12:42:52 pc smartd[2275]: Device: /dev/sda [SAT], self-test in progress, 10% remaining

You can increase the watchdog timeout to make it more permissive to such
scenario.

See https://bugzilla.redhat.com/show_bug.cgi?id=1300212 for a similar report.