In order to make changes to a shared buffer, one must hold a pin on itand the content lock in exclusive mode. This rule seems to befollowed in most of the places but there are a few exceptions.
One can find several PageInit() calls with no content lock held. See,for example:
Moreover, fsm_vacuum_page() performs"PageGetContents(page))->fp_next_slot = 0;" without content lock.
There may be more but I want to know if these can be treated asviolations before moving ahead.