[RFC] Add a feature to list which processes use (hold a ref to) kernel module

[Andrey Utkin]

There are smart answers around for the question "how to see which
processes use module and prohibid rmmod from working", like this one:
http://stackoverflow.com/a/15494206
But there is no easy way to check it "just in time", i.e. you have no
special debug settings set up, and you just want to know which
processes make module's refcnt positive.

Would such feature be considered useful? If yes, then also
guidance/mentorship would be appreciated (i am not experienced in
kernel development).