Errors stop ONLY after the kvm process killed with SIGKILL. I wait about 2 hours, but errors continue to appear, and writes to the disk get stuck:
Syslog:
Mar 30 14:31:15 kvm01 pvedaemon[59485]: VM 110 qmp command failed - VM 110 qmp command 'query-proxmox-support' failed - unable to connect...