"WARNING: Volume Group VGNAME is not consistent" when peforming pvmove operation

Issue

• Create a VM and install it using rhel6. Create 2 partitions of 100 MiB and 2 of 1 GiB.

Disk /dev/vdb: 5368 MB, 5368709120 bytes
9 heads, 40 sectors/track, 29127 cylinders, total 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xdb60f691

   Device Boot      Start         End      Blocks   Id  System
/dev/vdb1            2048    10485759     5241856    5  Extended
/dev/vdb5            4096      208895      102400   83  Linux
/dev/vdb6          210944      415743      102400   83  Linux
/dev/vdb7          417792     2514943     1048576   83  Linux
/dev/vdb8         2516992     4614143     1048576   83  Linux

Create the test LVM configuration:

# vgcreate vg_test1 /dev/vdb5 /dev/vdb6
# vgcreate vg_test2 /dev/vdb7 /dev/vdb8
# lvcreate -L 950 vg_test2 -n lv_test2 /dev/vdb7

• Run:

# while :; do pvmove /dev/vdb7 /dev/vdb8; pvmove /dev/vdb8 /dev/vdb7; done

• While this is in progress, open a second shell in the VM and run:

#while :; do vgextend vg_test1 /dev/vdb6 ; vgreduce vg_test1 /dev/vdb6 ; done

Warning messages are observed :

# while :; do pvmove /dev/vdb7 /dev/vdb8; pvmove /dev/vdb8 /dev/vdb7; done
  Skipping locked LV lv_test2
  All data on source PV skipped. It contains locked, hidden or non-top level LVs only.
  No data to move for vg_test2
  Detected pvmove in progress for /dev/vdb8
  Ignoring remaining command line arguments
  /dev/vdb8: Moved: 100.0%

  /dev/vdb7: Moved: 1.7%
  /dev/vdb7: Moved: 100.0%
  /dev/vdb8: Moved: 6.3%
  /dev/vdb8: Moved: 100.0%
  /dev/vdb7: Moved: 5.9%
  /dev/vdb7: Moved: 100.0%
  /dev/vdb8: Moved: 4.6%
  /dev/vdb8: Moved: 100.0%
  /dev/vdb7: Moved: 3.8%
  /dev/vdb7: Moved: 100.0%
  WARNING: Volume Group vg_test1 is not consistent.
  WARNING: Volume Group vg_test1 is not consistent.
  WARNING: Volume Group vg_test1 is not consistent.
  /dev/vdb8: Moved: 5.5%
  WARNING: Volume Group vg_test1 is not consistent.
  WARNING: Volume Group vg_test1 is not consistent.
  /dev/vdb8: Moved: 100.0%
  WARNING: Volume Group vg_test1 is not consistent.
  WARNING: Volume Group vg_test1 is not consistent.
  /dev/vdb7: Moved: 5.0%
  WARNING: Volume Group vg_test1 is not consistent.
  /dev/vdb7: Moved: 100.0%
  /dev/vdb8: Moved: 3.4%
  /dev/vdb8: Moved: 100.0%
...
[root@rhel6 ~]# while :; do vgextend vg_test1 /dev/vdb6 ; vgreduce vg_test1 /dev/vdb6 ; done
  Volume group "vg_test1" successfully extended
  Removed "/dev/vdb6" from volume group "vg_test1"
  Volume group "vg_test1" successfully extended
  Removed "/dev/vdb6" from volume group "vg_test1"
  Volume group "vg_test1" successfully extended
  Removed "/dev/vdb6" from volume group "vg_test1"
  Volume group "vg_test1" successfully extended
  Removed "/dev/vdb6" from volume group "vg_test1"
  Volume group "vg_test1" successfully extended
^C