How do I get a log for submodule ref pointer?

Question

My submodule ref pointer was moved back a few revisions and I would like to know who commited that change to our main repo, how can I do that? How can I get a log just for submodule reference? Because going through every commit searching for changed submodule reference is not an option.

Answer 1

You can simply check the log for the gitlink representing your submodule in your parent repo:

git log -- yourSubmodule

No trailing '/' here: yoursubmodule is the name of the folder in which your submodule is checked out.
But it is also the name of the gitlink (special entry mode 160000) recording that submodule in the parent repo.

That will list only the commits in which yoursubmodule gitlink has changed.