Fix race in SSI interaction with gin fast path.
The ginfast.c code previously checked for conflicts in before locking
the relevant buffer, leaving a window where a RW conflict could be
missed. Re-order.
There was also a place where buffer ID and block number were confused
while trying to predicate-lock a page, noted by visual inspection.
Back-patch to all supported releases. Fixes one more problem discovered
with the reproducer from bug #17949, in this case when Dmitry tried
other index types.
Reported-by: Artem Anisimov <artem.anisimov.255@gmail.com>
Reported-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/17949-a0f17035294a55e2%40postgresql.org
Branch
------
REL_16_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/12529028a4e55eb0500477d2589eec625466facf
Modified Files
--------------
src/backend/access/gin/ginfast.c | 9 +++++++--
src/backend/access/gin/ginget.c | 4 +++-
2 files changed, 10 insertions(+), 3 deletions(-)
