...blocked for more than 120 seconds

Hello!
I started to get these error messages about once a month, but when I get this the whole system freezes and the only way is the hard reset.

INFO: task systemd-logind:741 blocked for more than 120 seconds
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message
INFO: task mysqld:1847 blocked for more than 120 seconds
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message
INFO: task auditd: 716 blocked for more than 120 seconds
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message
...

What can cause this?

My guess would be running on a virtual machine that is being moved between hosts.

Looking at process - What does "task mysqld:xxx blocked for more than 120 seconds" mean? - Unix & Linux Stack Exchange it looks like it could also indicate a failing disk, or a severe shortage of RAM.