diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 5c3ca479fb33fff646e3a7b08b53efea92b9a97f..aa0b0291ee1c7781a36c62e3d89abbc98d3b8499 100644
*** a/src/backend/access/transam/xlog.c
--- b/src/backend/access/transam/xlog.c
*************** ReadRecord(XLogRecPtr *RecPtr, int emode
*** 3728,3750 ****
  		RecPtr = &tmpRecPtr;
  
  		/*
! 		 * Align recptr to next page if no more records can fit on the current
! 		 * page.
  		 */
  		if (XLOG_BLCKSZ - (RecPtr->xrecoff % XLOG_BLCKSZ) < SizeOfXLogRecord)
! 		{
! 			NextLogPage(tmpRecPtr);
! 			/* We will account for page header size below */
! 		}
  
! 		if (tmpRecPtr.xrecoff >= XLogFileSize)
  		{
! 			(tmpRecPtr.xlogid)++;
! 			tmpRecPtr.xrecoff = 0;
  		}
  	}
  	else
  	{
  		if (!XRecOffIsValid(RecPtr->xrecoff))
  			ereport(PANIC,
  					(errmsg("invalid record offset at %X/%X",
--- 3728,3759 ----
  		RecPtr = &tmpRecPtr;
  
  		/*
! 		 * RecPtr is pointing to end+1 of the previous WAL record.  We must
! 		 * advance it if necessary to where the next record starts.  First,
! 		 * align to next page if no more records can fit on the current page.
  		 */
  		if (XLOG_BLCKSZ - (RecPtr->xrecoff % XLOG_BLCKSZ) < SizeOfXLogRecord)
! 			NextLogPage(*RecPtr);
  
! 		/* Check for crossing of xlog segment boundary */
! 		if (RecPtr->xrecoff >= XLogFileSize)
  		{
! 			(RecPtr->xlogid)++;
! 			RecPtr->xrecoff = 0;
  		}
+ 
+ 		/*
+ 		 * If at page start, we must skip over the page header.  But we can't
+ 		 * do that until we've read in the page, since the header size is
+ 		 * variable.
+ 		 */
  	}
  	else
  	{
+ 		/*
+ 		 * In this case, the passed-in record pointer should already be
+ 		 * pointing to a valid record starting position.
+ 		 */
  		if (!XRecOffIsValid(RecPtr->xrecoff))
  			ereport(PANIC,
  					(errmsg("invalid record offset at %X/%X",
*************** retry:
*** 3773,3783 ****
  	if (targetRecOff == 0)
  	{
  		/*
! 		 * Can only get here in the continuing-from-prev-page case, because
! 		 * XRecOffIsValid eliminated the zero-page-offset case otherwise. Need
! 		 * to skip over the new page's header.
  		 */
! 		tmpRecPtr.xrecoff += pageHeaderSize;
  		targetRecOff = pageHeaderSize;
  	}
  	else if (targetRecOff < pageHeaderSize)
--- 3782,3794 ----
  	if (targetRecOff == 0)
  	{
  		/*
! 		 * At page start, so skip over page header.  The Assert checks that
! 		 * we're not scribbling on caller's record pointer; it's OK because we
! 		 * can only get here in the continuing-from-prev-record case, since
! 		 * XRecOffIsValid rejected the zero-page-offset case otherwise.
  		 */
! 		Assert(RecPtr == &tmpRecPtr);
! 		RecPtr->xrecoff += pageHeaderSize;
  		targetRecOff = pageHeaderSize;
  	}
  	else if (targetRecOff < pageHeaderSize)
diff --git a/src/include/access/xlog_internal.h b/src/include/access/xlog_internal.h
index eeccdce31d076322cc5431117c6705b839b1b162..7e39630c1bf5d7cbf1a721b641a9481069e92816 100644
*** a/src/include/access/xlog_internal.h
--- b/src/include/access/xlog_internal.h
*************** typedef XLogLongPageHeaderData *XLogLong
*** 154,166 ****
  /* Align a record pointer to next page */
  #define NextLogPage(recptr) \
  	do {	\
! 		if (recptr.xrecoff % XLOG_BLCKSZ != 0)	\
! 			recptr.xrecoff +=	\
! 				(XLOG_BLCKSZ - recptr.xrecoff % XLOG_BLCKSZ);	\
! 		if (recptr.xrecoff >= XLogFileSize) \
  		{	\
! 			(recptr.xlogid)++;	\
! 			recptr.xrecoff = 0; \
  		}	\
  	} while (0)
  
--- 154,166 ----
  /* Align a record pointer to next page */
  #define NextLogPage(recptr) \
  	do {	\
! 		if ((recptr).xrecoff % XLOG_BLCKSZ != 0)	\
! 			(recptr).xrecoff +=	\
! 				(XLOG_BLCKSZ - (recptr).xrecoff % XLOG_BLCKSZ);	\
! 		if ((recptr).xrecoff >= XLogFileSize) \
  		{	\
! 			((recptr).xlogid)++;	\
! 			(recptr).xrecoff = 0; \
  		}	\
  	} while (0)