diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 3cb5120..7d3d8cc 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -1292,12 +1292,17 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 	 * paranoia.  We also reset the usage_count since any recency of use of
 	 * the old content is no longer relevant.  (The usage_count starts out at
 	 * 1 so that the buffer can survive one clock-sweep pass.)
+	 *
+	 * Make sure BM_PERMANENT is set for buffers that must be written at
+	 * every checkpoint.  Unlogged buffers only need to be written at shutdown
+	 * checkpoints, except for their "init" forks, which need to be treated
+	 * just like permanent relations.
 	 */
 	buf->tag = newTag;
 	buf_state &= ~(BM_VALID | BM_DIRTY | BM_JUST_DIRTIED |
 				   BM_CHECKPOINT_NEEDED | BM_IO_ERROR | BM_PERMANENT |
 				   BUF_USAGECOUNT_MASK);
-	if (relpersistence == RELPERSISTENCE_PERMANENT)
+	if (relpersistence == RELPERSISTENCE_PERMANENT || forkNum == INIT_FORKNUM)
 		buf_state |= BM_TAG_VALID | BM_PERMANENT | BUF_USAGECOUNT_ONE;
 	else
 		buf_state |= BM_TAG_VALID | BUF_USAGECOUNT_ONE;