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

[Matthias Kretschmer <kretschm%cs.uni-bonn.de@localhost>]

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: Wed, 7 Sep 2011 08:43:03 +0200

 On Tue, Sep 06, 2011 at 11:05:06AM +0000, Christos Zoulas wrote:
 >  1. fstat will not show unix sockets open in the filesystem. I have updated
 >  fstat on head to mention this, as well as to print the pathnames for open
 >  sockets when no arguments are given.
 
 Is the information of the more modern fstat important?  Then I could try
 to update, but due to space limitations on my iBook where I have the
 problem I would prefer to avoid that.
 
 >  2. Can you compile and run lsof from pkgsrc? what does that say?
 
 See the output below.
 
 
 I'm quite sure I can reproduce this now for the NFS mount point.  The
 steps are as follows:
 - mount /netboot (nfs), /netboot/tmp (nullfs from tmpfs),
   /netboot/wrkobjdir (nullfs from ffs)
 - chroot to /netboot (/netboot contains a complete macppc tree which is
   used to netboot from)
 - perform in the chroot
     # pkg_delete -r xulrunner
     # packageall (some script which ensures that only the binary
                   packages of installed packages are available)
     # pkg_chk -a -s
       (building devel/xulrunner & www/firefox from HEAD)
     # packageall (again ...)
 - outside the chroot I run two scripts pkg_sync & pkg_markauto which
   ensure that all binary packages from the chroot and only those are
   installed in / and copy the automatic installed information from the
   chroot.
 
 So the interaction with the /netboot-NFS-mount-point is basically
 removing xulrunner and firefox packages, installing them again, and
 creating a few (5) intermediate files with lists of installed packages
 and listings of tar-balls available at /usr/pkgsrc/packages/All.
 
 
 I had the same problem with /netboot/wrkobjdir but happened only after
 compiling 100+ packages and I prefer not to do that at the moment.
 
 
 The requested outputs of lsof and mount/umount (I do not repost fstat as
 there is no change as is the case for ps ax):
 
 # lsof | grep netboot
 # lsof > lsof.txt
 # cat lsof.txt
 COMMAND   PID USER   FD   TYPE DEVICE SIZE/OFF   NODE NAME
 system      0 root  cwd   VDIR   10,0      512      2 /
 init        1 root  cwd   VDIR   10,0      512      2 /
 init        1 root  txt   VREG   10,0    28026  31919 /sbin/init
 init        1 root  txt   VREG   10,0  1305621  21252 /lib/libc.so.12.164
 init        1 root  txt   VREG   10,0    29811  21255 /lib/libcrypt.so.0.2
 init        1 root  txt   VREG   10,0    93732  21288 /lib/libutil.so.7.15
 init        1 root  txt   VREG   10,0    79436  31882 /libexec/ld.elf_so
 login   11125 root  cwd   VDIR   10,0      512  31885 /root
 login   11125 root  txt   VREG   10,4    22540 569731 /usr/bin/login
 login   11125 root  txt   VREG   10,4    11032 114285 
/usr/lib/security/pam_lastlog.so.1
 login   11125 root  txt   VREG   10,4    10212 114286 
/usr/lib/security/pam_login_access.so.1
 login   11125 root  txt   VREG   10,4     7504 114292 
/usr/lib/security/pam_securetty.so.1
 login   11125 root  txt   VREG   10,4    67132 114165 /usr/lib/librpcsvc.so.0.0
 login   11125 root  txt   VREG   10,4    15548 114296 
/usr/lib/security/pam_unix.so.1
 login   11125 root  txt   VREG   10,4    23653 114090 /usr/lib/libkafs.so.9.0
 login   11125 root  txt   VREG   10,4     7742 114275 
/usr/lib/security/pam_afslog.so.1
 login   11125 root  txt   VREG   10,4   295015 114063 /usr/lib/libhx509.so.2.0
 login   11125 root  txt   VREG   10,0  1982775  21258 /lib/libcrypto.so.4.2
 login   11125 root  txt   VREG   10,4     8405 114018 
/usr/lib/libcom_err.so.5.0
 login   11125 root  txt   VREG   10,4    75627 114162 /usr/lib/libroken.so.13.0
 login   11125 root  txt   VREG   10,4   550706 113998 /usr/lib/libasn1.so.7.0
 login   11125 root  txt   VREG   10,4   479989 114093 /usr/lib/libkrb5.so.22.0
 login   11125 root  txt   VREG   10,4    22511 114283 
/usr/lib/security/pam_krb5.so.1
 login   11125 root  txt   VREG   10,4    30129 114237 /usr/lib/libskey.so.1.0
 login   11125 root  txt   VREG   10,4     6941 114294 
/usr/lib/security/pam_skey.so.1
 login   11125 root  txt   VREG   10,4     7716 114287 
/usr/lib/security/pam_nologin.so.1
 login   11125 root  txt   VREG   10,4     6134 114293 
/usr/lib/security/pam_self.so.1
 login   11125 root  txt   VREG   10,0  1305621  21252 /lib/libc.so.12.164
 login   11125 root  txt   VREG   10,4    37846 114129 /usr/lib/libpam.so.1.0
 login   11125 root  txt   VREG   10,0    29811  21255 /lib/libcrypt.so.0.2
 login   11125 root  txt   VREG   10,0    93732  21288 /lib/libutil.so.7.15
 login   11125 root  txt   VREG   10,0    79436  31882 /libexec/ld.elf_so
 login   11125 root    0u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 login   11125 root    1u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 login   11125 root    2u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 lsof    18029 root  cwd   VDIR   10,0      512  32000 /root/pr-infos
 lsof    18029 root  txt   VREG   10,4   129888 231925 /usr/pkg/sbin/lsof
 lsof    18029 root  txt   VREG   10,0  1305621  21252 /lib/libc.so.12.164
 lsof    18029 root  txt   VREG   10,0    34607  21270 /lib/libkvm.so.5.3
 lsof    18029 root  txt   VREG   10,0    79436  31882 /libexec/ld.elf_so
 lsof    18029 root    0u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 lsof    18029 root    1w  VREG   10,0        0  32002 / (/dev/wd0a)
 lsof    18029 root    2u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 lsof    18029 root    3r  VCHR    2,0      0t0  53828 /dev/mem
 lsof    18029 root    4r  VCHR    2,1      0t0  53827 /dev/kmem
 lsof    18029 root    5r  VCHR    6,0      0t0  53826 /dev/drum
 lsof    18029 root    6r  VCHR   74,0      0t0  53832 /dev/ksyms
 sh      18323 root  cwd   VDIR   10,0      512  32000 /root/pr-infos
 sh      18323 root  txt   VREG   10,0   168953  42526 /bin/sh
 sh      18323 root  txt   VREG   10,0  1305621  21252 /lib/libc.so.12.164
 sh      18323 root  txt   VREG   10,0    15179  21282 /lib/libtermcap.so.0.6
 sh      18323 root  txt   VREG   10,0   147621  21261 /lib/libedit.so.2.11
 sh      18323 root  txt   VREG   10,0    79436  31882 /libexec/ld.elf_so
 sh      18323 root    0u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 sh      18323 root    1u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 sh      18323 root    2u  VCHR   35,0  0t17908  53128 /dev/ttyE0
 sh      18323 root  127u  VCHR    1,0      0t0  53833 /dev/tty
 
 # cat /proc/mounts
 /dev/wd0a / ffs rw 0 0
 /dev/wd0g /var ffs rw 0 0
 /dev/wd0e /usr ffs rw 0 0
 /dev/cgd0c /home ffs rw 0 0
 tmpfs /tmp tmpfs rw 0 0
 kernfs /kern kernfs rw 0 0
 ptyfs /dev/pts ptyfs rw 0 0
 procfs /proc proc rw 0 0
 <host>:/home/macppc/root /netboot nfs rw 0 0
 
 # umount -F /netboot
 /home/macppc/root: unmount from /netboot
 umount: /netboot: Device busy.
 # umount -f /netboot
 #
 
 
 --
 Matthias Kretschmer