> Discarding device blocks: done
> Creating filesystem with 307200 1k blocks and 76912 inodes
> ......
> # pvs
>   /dev/LOOP_VG/LV: read failed after 0 of 1024 at 0: Invalid argument
>   /dev/LOOP_VG/LV: read failed after 0 of 1024 at 314507264: Invalid argument
>   /dev/LOOP_VG/LV: read failed after 0 of 1024 at 314564608: Invalid argument
>   /dev/LOOP_VG/LV: read failed after 0 of 1024 at 4096: Invalid argument
>   PV                   VG      Fmt  Attr PSize   PFree
>   /dev/loop0           LOOP_VG lvm2 a--  496.00m 496.00m
>   /dev/mapper/enc-loop LOOP_VG lvm2 a--  492.00m 192.00m
> 
> In case the filesystem of the logical volume is not mounted at the time of pvmove, it gets corrupted anyway, but you only see errors when trying to mount it.
> 

It's because you FS had 1k blocks.
New device can't read with block 1k.
If you plan pvmove on device with 4k. Maybe you need make fs with:
"mkfs.ext4 -b 4096"

See comments:
https://bugzilla.redhat.com/show_bug.cgi?id=1684078