Make HEAP_LOCK/HEAP2_LOCK_UPDATED replay reset HEAP_XMAX_INVALID.

anarazel · anarazel · commit a4d357bfbd56 · 2016-07-15T14:45:37.000-07:00
0ac5ad5 started to compress infomask bits in WAL records. Unfortunately the replay routines for XLOG_HEAP_LOCK/XLOG_HEAP2_LOCK_UPDATED forgot to reset the HEAP_XMAX_INVALID (and some other) hint bits. Luckily that's not problematic in the majority of cases, because after a crash/on a standby row locks aren't meaningful. Unfortunately that does not hold true in the presence of prepared transactions. This means that after a crash, or after promotion, row level locks held by a prepared, but not yet committed, prepared transaction might not be enforced. Discussion: 20160715192319.ubfuzim4zv3rqnxv@alap3.anarazel.de Backpatch: 9.3, the oldest branch on which 0ac5ad5 is present.
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
@@ -8687,6 +8687,8 @@ heap_xlog_lock(XLogReaderState *record)
 
 		htup = (HeapTupleHeader) PageGetItem(page, lp);
 
+		htup->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
+		htup->t_infomask2 &= ~HEAP_KEYS_UPDATED;
 		fix_infomask_from_infobits(xlrec->infobits_set, &htup->t_infomask,
 								   &htup->t_infomask2);
 
@@ -8737,6 +8739,8 @@ heap_xlog_lock_updated(XLogReaderState *record)
 
 		htup = (HeapTupleHeader) PageGetItem(page, lp);
 
+		htup->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
+		htup->t_infomask2 &= ~HEAP_KEYS_UPDATED;
 		fix_infomask_from_infobits(xlrec->infobits_set, &htup->t_infomask,
 								   &htup->t_infomask2);
 		HeapTupleHeaderSetXmax(htup, xlrec->xmax);
