FYI, we noticed the below changes on
https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git chardev
commit 3c702e9987e261042a07e43460a8148be254412e ("gpio: add a userspace chardev ABI
for GPIOs")
[ 1.951191] user_verbs: couldn't register device number
[ 1.952527] ucm: couldn't register device number
Thanks,
Ying Huang