FYI, we noticed the below changes on

git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
commit 9f53f9fa4ad1d8bddd4d14359cdabc531aedffe8 ("libnvdimm, pmem: add
libnvdimm support to the pmem driver")

We found the following new message in kernel log.

[   17.884728] user_verbs: couldn't register device number
[   17.884728] user_verbs: couldn't register device number
[   17.886026] ucm: couldn't register device number
[   17.886026] ucm: couldn't register device number

Thanks,
Ying Huang