Bug#549691: lvm2: snapshot claims open when nothing using it; can't be removed

[Daniel Dickinson]

Package: lvm2
Version: 2.02.66-5
Severity: normal


1) Create lvm snapshot of root partition
2) Do backup
3) Unmount
4) lvremove group/volume-snapshot fails claiming open

mount doesn't report it as mounted
/proc/mounts doesn't have an entry for it
it's not swap

dmsetup remove volume--snaphot
and
dmsetup remove volume--snapshot-cow

then 

lvremove group/volume-snapshot

works

But why isn't it working with just lvremove?  It used to work on Lenny (though I wasn't using this backup method for a while so I don't know at what versions it became a problem).

oh, yes, as mentioned

lvchange -an  group/volume-snapshot

fails.

Could a maintainer ask a question I can check the answer to, that would help with the debug?  I suspect some ansychronous event thing is happening with udev or somesuch.



-- System Information:
Debian Release: wheezy/sid
  APT prefers squeeze-updates
  APT policy: (500, 'squeeze-updates'), (500, 'testing'), (100, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.32-5-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_CA.UTF-8, LC_CTYPE=en_CA.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages lvm2 depends on:
ii  dmsetup                      2:1.02.48-5 The Linux Kernel Device Mapper use
ii  libc6                        2.11.2-11   Embedded GNU C Library: Shared lib
ii  libdevmapper1.02.1           2:1.02.48-5 The Linux Kernel Device Mapper use
ii  libreadline5                 5.2-7       GNU readline and history libraries
ii  libudev0                     164-3       libudev shared library
ii  lsb-base                     3.2-27      Linux Standard Base 3.2 init scrip

lvm2 recommends no packages.

lvm2 suggests no packages.

-- no debconf information