Thor module continues running although rescontrol should have stopped it

[furrnace]

> 3/3 > Running module 'Filesystem Checks'                                     
Info Starting module
Info The following paths will be scanned: /                                                                                                               
Info Scanning / RECURSIVE                                                                                                                                 
Error Available physical memory dropped below 50 MB, stopping THOR scan in order to avoid a memory outage (use --norescontrol to avoid this)              
Notice Process with high memory usage PID: 12973 NAME: thor-lite-linux-64 COMMAND: ./thor-lite-linux-64 MEMORY_USAGE: 61.17%                              
Notice Process with high memory usage PID: 12938 NAME: sshd COMMAND: sshd: root@pts/0 MEMORY_USAGE: 1.44%                                                 
Notice Process with high memory usage PID: 12409 NAME: named COMMAND: /usr/sbin/named -u bind MEMORY_USAGE: 1.26%                                         
Info Wrote THOR memory profile                                                                                                                            
FILE: /mnt/security/thor/thor10.7lite-linux-pack/heap.pprof
Info Storing current position for resume. Use --resume in addition to the current command line options to resume later.                                   
Info Successfully closed ThorDB                                                                                                                           
[89%] /usr/lib/modules/4.19....ers/xen/xenfs/xenfs.ko  [#####################################################################################>___________]

The module continues scanning files for a while after THOR announced to stop the scan, and then freezes. Only kill -9 helps to get rid of the frozen THOR processes.