Created attachment 1481329 [details]
Used partition model – LVM option– left available data storage size

Description of problem: LBSK function output exhibits twice the information related to a same LVM group.

Version-Release number of component:
util-linux.x86_64                          2.32-2.fc28                 @anaconda
util-linux.x86_64                          2.32.1-1.fc28               @System

For a reason I cannot explain, using the command 'dnf list installed | grep util-linux', it revealed that component Util-linux is installed in two different versions from different repositories,

How reproducible: set partition according to the model illustrated in attachment; One extra LVM group is created for data to be used as storage pool by QEMU-KVM. The group itself is not encrypted; only one logical volume within it, is.

Actual results: 
$ lsblk
NAME                                MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                                   8:0    0 232.9G  0 disk  
├─sda1                                8:1    0     1G  0 part  /boot
├─sda2                                8:2    0    20G  0 part  
│ ├─fedora-root                     253:0    0    16G  0 lvm   /
│ └─fedora-swap                     253:1    0     4G  0 lvm   [SWAP]
└─sda3                                8:3    0 200.1G  0 part  
  ├─qemu--kvm-pool00_tmeta          253:2    0    20M  0 lvm   
  │ └─qemu--kvm-pool00-tpool        253:4    0   160G  0 lvm   
  │   ├─qemu--kvm-pool00            253:5    0   160G  0 lvm   
  │   ├─qemu--kvm-iso--disc--images 253:6    0    32G  0 lvm   /virt/iso-disc-im
  │   └─qemu--kvm-disc--images      253:7    0   128G  0 lvm   
  │     └─luks-587a34fa-e959-4c37-9e9e-2c094c55cf9c
  │                                 253:8    0   128G  0 crypt /virt/disc-images
  └─qemu--kvm-pool00_tdata          253:3    0   160G  0 lvm   
    └─qemu--kvm-pool00-tpool        253:4    0   160G  0 lvm   
      ├─qemu--kvm-pool00            253:5    0   160G  0 lvm   
      ├─qemu--kvm-iso--disc--images 253:6    0    32G  0 lvm   /virt/iso-disc-im
      └─qemu--kvm-disc--images      253:7    0   128G  0 lvm   
        └─luks-587a34fa-e959-4c37-9e9e-2c094c55cf9c
                                    253:8    0   128G  0 crypt /virt/disc-images

The original LVM group name 'qemu-kvm' is unexpectedly interpreted as 'qemu--kvm-pool00_tmeta', in which character '-' is changed to '--'. 

Expected results: partition related to a volume group whom one of its an LVM logical volume is using thin partitioning, to be listed once. LVM group name to match the original one set at the system installation.

Additional info:
$ df -hTt ext4
Filesystem                              Type  Size  Used Avail Use% Mounted on
/dev/mapper/fedora-root                 ext4   16G  7.5G  7.4G  51% /
/dev/sda1                               ext4  976M  187M  723M  21% /boot
/dev/mapper/qemu--kvm-iso--disc--images ext4   32G   49M   30G   1% /virt/iso-disc-images
/dev/dm-8                               ext4  125G   61M  119G   1% /virt/disc-images

Partition /dev/dm-8 is listed here once as expected