1) make the test use put_user()
2) move the rodata_test() call and the prototype to a common location
3) move the test out to mm/ (with no changes to file itself)

Where is the best place for common test file in general??

kernel/rodata_test.c

include/rodata_test.h => Is it fine??

I can't see common file about rodata.

So I'm confused where the best place is.