Description of problem:

automount force unlink option (-F) does not work as expected on autofs-5.0.7-109.el7

according to man this option should clean up / unlink any mount present from previous incarnation :

==============================
  -F, --force

Force an unlink umount of existing mounts under autofs managed mount points during startup. 
This can cause problems for processes with working directories within these mounts (see NOTES).
==============================

But does not work as expected on RHEL7.8, autofs-5.0.7-109.el7 :

[root@rhel77 ~]# automount -V | grep version
Linux automount version 5.0.7-109.el7

[root@rhel77 ~]# grep -iE "autofs|nfs" /proc/mounts 
systemd-1 /proc/sys/fs/binfmt_misc autofs rw,relatime,fd=22,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=9826 0 0
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw,relatime 0 0
/etc/auto.misc /misc autofs rw,relatime,fd=5,pgrp=7726,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=46267 0 0
-hosts /net autofs rw,relatime,fd=11,pgrp=7726,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=45820 0 0
/etc/auto.test /direct_test/test autofs rw,relatime,fd=17,pgrp=7726,timeout=300,minproto=5,maxproto=5,direct,pipe_ino=45824 0 0

[root@rhel77 ~]# cd /direct_test/test
[root@rhel77 test]# pkill -9 automount
[root@rhel77 test]# /usr/sbin/automount -d --pid-file /run/autofs.pid -F

[root@rhel77 test]# grep -iE "autofs|nfs" /proc/mounts
systemd-1 /proc/sys/fs/binfmt_misc autofs rw,relatime,fd=22,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=9826 0 0
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw,relatime 0 0
/etc/auto.test /direct_test/test autofs rw,relatime,fd=17,pgrp=7726,timeout=300,minproto=5,maxproto=5,direct,pipe_ino=45824 0 0
rhel73:/5GBshare /direct_test/test nfs4 rw,relatime,vers=4.1,rsize=262144,wsize=262144,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,clientaddr=172.23.1.247,local_lock=none,addr=172.23.1.225 0 0

---> both autofs/NFS entries still present, autofs still have old process group

/etc/auto.misc /misc autofs rw,relatime,fd=7,pgrp=7756,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=45880 0 0
-hosts /net autofs rw,relatime,fd=13,pgrp=7756,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=46312 0 0
/etc/auto.test /direct_test/test autofs rw,relatime,fd=19,pgrp=7756,timeout=300,minproto=5,maxproto=5,direct,pipe_ino=46316 0 0

This worked as expected on 5.0.7-106.el7 :

[root@rhel77 ~]# automount -V | grep version
Linux automount version 5.0.7-106.el7

[root@rhel77 ~]# grep -iE "autofs|nfs" /proc/mounts 
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw,relatime 0 0
/etc/auto.test /direct_test/test autofs rw,relatime,fd=16,pgrp=11931,timeout=300,minproto=5,maxproto=5,direct,pipe_ino=46048 0 0
/etc/auto.misc /misc autofs rw,relatime,fd=5,pgrp=11931,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=46668 0 0
-hosts /net autofs rw,relatime,fd=11,pgrp=11931,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=46046 0 0

[root@rhel77 ~]# cd /direct_test/test
[root@rhel77 test]# pkill -9 automount
[root@rhel77 test]# /usr/sbin/automount -d --pid-file /run/autofs.pid -F

[root@rhel77 test]# grep -iE "autofs|nfs" /proc/mounts
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw,relatime 0 0
/etc/auto.misc /misc autofs rw,relatime,fd=7,pgrp=11964,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=46713 0 0
-hosts /net autofs rw,relatime,fd=13,pgrp=11964,timeout=300,minproto=5,maxproto=5,indirect,pipe_ino=46722 0 0
/etc/auto.test /direct_test/test autofs rw,relatime,fd=19,pgrp=11964,timeout=300,minproto=5,maxproto=5,direct,pipe_ino=46726 0 0


Version-Release number of selected component (if applicable):

autofs-5.0.7-109.el7


How reproducible: 100%


Steps to Reproduce:

1. See Description for reproducer
2.
3.

Actual results: autofs referencing previous autofs incarnation still around


Expected results: unlink entries


Additional info: