I create a repo "main", containing a submodule "sub0", containing a submodule "sub1":
mkdir sub0 && cd sub0 && git init && touch README.md && git add README.md && git commit -am "Initial" && cd ..
mkdir sub1 && cd sub1 && git init && git submodule add ../sub0 sub0 && git commit -am "Initial" && cd ..
mkdir main && cd main && git init && git submodule add ../sub1 sub1 && git commit -am "Initial" && cd ..
I also tried
git submodule update --init --recursive
in main, but it makes not difference for the following issue.
Now, I got to main/sub1/, and make a change to the submodule configuration:
git config submodule.sub0.update none
For some strange reason, this change ends up in ../.git/modules/sub1/config instead of in .gitmodules. Now, how do I push this change? git shows me no modified files in any of the repos.