Bug 997897

Description of problem:
For testing / debugging of OpenStack, a volume group with a file-backend is often created, e.g. https://fedoraproject.org/wiki/QA:Testcase_Create_Cinder_Volumes

Now, it looks like after a reboot, the PV and VG created like this are no longer recognized by pvscan/vgscan/pvchange/vgchange.

Version-Release number of selected component (if applicable):
lvm2-2.02.98-11.fc19.x86_64

How reproducible:
Always(?)

Steps to Reproduce & results:
[root@openstack ~]# truncate -s1G test
[root@openstack ~]# losetup -f --show test
/dev/loop1
[root@openstack ~]# vgcreate test /dev/loop1
  No physical volume found in lvmetad cache for /dev/loop1
  Physical volume "/dev/loop1" successfully created
  Volume group "test" successfully created
[root@openstack ~]# vgscan
  Reading all physical volumes.  This may take a while...
  Found volume group "test" using metadata type lvm2
[root@openstack ~]# sync
[root@openstack ~]# losetup -d /dev/loop1
[root@openstack ~]# reboot
Connection to 192.168.0.158 closed by remote host.
Connection to 192.168.0.158 closed.
[red_trela@tiphares ~]$ ssh root.0.158
root.0.158's password:
Last login: Fri Aug 16 14:41:13 2013 from 192.168.0.1
[root@openstack ~]# losetup -f --show test
/dev/loop1
[root@openstack ~]# vgscan
  Reading all physical volumes.  This may take a while...
  No volume groups found
[root@openstack ~]# pvscan
  No matching physical volumes found

Additional information:
Using md5sum, I confirmed that both pvcreate and vgcreate modify the file and that it is unmodified (compared to post-vgcreate) after a reboot.