VBoxSVC holds vm xml definition file open after VM is unregistered

[James Lucas]

Executing a VBoxManage unregistervm <vmname> successfully unregisters the VM from the host. VBoxSVC fails to close the vm definition xml file and continues to hold open a R/W lock (FD flag u). This is noticeable if another VM is running because VBoxSVC will continue to run. VBoxSVC should close any open files belonging to a vm when unregistering it.

lsof output shows

COMMAND     PID      USER   FD      TYPE             DEVICE       SIZE       NODE NAME
VBoxSVC   27907    vmuser   25u      REG               0,24       3053  106102849 /vmuser/vmachines/Machines/1084/1084.xml