freespace: Don't modify page without any lock Before this commit fsm_vacuum_page() modified the page without any lock on the page. Historically that was kind of ok, as we didn't rely on the freespace to really stay consistent and we did not have checksums. But these days pages are checksummed and there are ways for FSM pages to be included in WAL records, even if the FSM itself is still not WAL logged. If a FSM page ever were modified while a WAL record referenced that page, we'd be in trouble, as the WAL CRC could end up getting corrupted.
The reason to address this right now is a series of patches with the goal to only allow modifications of pages with an appropriate lock level. Obviously not having any lock is not appropriate :) Reviewed-by: Kirill Reshke <[email protected]> Discussion: https://postgr.es/m/4wggb7purufpto6x35fd2kwhasehnzfdy3zdcu47qryubs2hdz@fa5kannykekr Discussion: https://postgr.es/m/[email protected] Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/45f658dacb9c2d333893fcf0d6b5a5e4f8ee5752 Modified Files -------------- src/backend/storage/freespace/freespace.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
