[ovirt-users] Zombie kworker process on node took 100% CPU load

Hi, I've got strange problem with oVirt Node 4.2 installed on CentOS 7 with mainline 4.14 kernel & HP ProLiant ML350. Kworker process loaded 1 cpu CPU core at 100%, and since it didn't finish even after several hours, it was clearly a zombie. I logged into each VM, and powered them off with "shutdown now". From SPICE console it was seen VMs halted. However, in oVirt engine web they have been marked with tripple green down arrow. An attempt to shutdown them completely with oVirt button resulted in error message something like "Can't shutdown VM because highly available and can't be moved". Sorry, I forgot to take screenshot. Its was also impossible to shutdown the node correctly, process freezes. After restart, everything seem to work correctly. Anyone have any idea how to cope with this kind of problem? Thanks in advance Andrei