I got a bug report from the upstream developer, he said, in the latest
versions, LVM2 can overwrite extents beyond metadata area. 

A critical bug has been found in LVM which can cause data corruption in rare
cases.  Avoid using LVM commands that change Volume Group metadata (e.g.
lvcreate, lvextend) while LVs in the VG are being used.

An I/O bug can cause LVM commands to read and write back the first 128KB of
data immediately following the LVM metadata at the start of the disk.  If these
blocks are being modified by another program (or file system) at the same time
as the LVM command, then that program's changes could be lost.

A fix is being evaluated and will be provided as soon as possible.

The more details can be found at the link 
https://bugzilla.redhat.com/show_bug.cgi?id=1643651