Re: kern/45305: umount says device busy without any process having current directory in the mount or file open

[christos%zoulas.com@localhost (Christos Zoulas)]

On Sep 27,  5:40am, kretschm%cs.uni-bonn.de@localhost (Matthias Kretschmer) 
wrote:
-- Subject: Re: kern/45305: umount says device busy without any process havin

| The following reply was made to PR kern/45305; it has been noted by GNATS.
| 
| From: Matthias Kretschmer <kretschm%cs.uni-bonn.de@localhost>
| To: gnats-bugs%NetBSD.org@localhost
| Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
|       netbsd-bugs%netbsd.org@localhost
| Subject: Re: kern/45305: umount says device busy without any process having 
current directory in the mount or file open
| Date: Tue, 27 Sep 2011 07:35:42 +0200
| 
|  Hi,
|  
|  I just want to add, that now I have data to the problem when even
|  the nullfs is not unmountable (or even both nullfs and nfs) ...
|  
|  # lsof | grep netboot
|  # lsof /netboot/wrkobjdir
|  # umount /netboot/wrkobjdir
|  umount: /netboot/wrkobjdir: Device busy
|  # mount
|  /dev/wd0a on / type ffs (local)
|  /dev/wd0g on /var type ffs (local)
|  /dev/wd0e on /usr type ffs (local)
|  /dev/cgd0c on /home type ffs (local)
|  tmpfs on /tmp type tmpfs (local)
|  kernfs on /kern type kernfs (local)
|  ptyfs on /dev/pts type ptyfs (local)
|  procfs on /proc type procfs (local)
|  pid231@blavet:/net on /net type nfs (hidden)
|  pid231@blavet:/media on /media type nfs (hidden)
|  nfshost:/home/macppc/root on /netboot type nfs
|  /home/wrkobjdir on /netboot/wrkobjdir type null (local)
|  # umount -f /netboot/wrkobjdir
|  # umount /netboot
|  umount: /netboot: Device busy
|  # umount -f /netboot
|  # 

Do you have a recipe for recreating the problem?

christos