Fixed DATA_FOR_UPDATE loading in WikiPage.

Change-Id: Ifc4259942eb8bf5e91e80ec0009c2a2ab191ae11

diff --git a/includes/WikiPage.php b/includes/WikiPage.php
index 6d9170a..2de1626 100644 (file)
--- a/includes/WikiPage.php
+++ b/includes/WikiPage.php
@@ -540,7 +540,14 @@ class WikiPage extends Page {
                        return; // page doesn't exist or is missing page_latest info
                }
 
-               $revision = Revision::newFromPageId( $this->getId(), $latest );
+               // Bug 37225: if session S1 loads the page row FOR UPDATE, the result always includes the
+               // latest changes committed. This is true even within REPEATABLE-READ transactions, where
+               // S1 normally only sees changes committed before the first S1 SELECT. Thus we need S1 to
+               // also gets the revision row FOR UPDATE; otherwise, it may not find it since a page row
+               // UPDATE and revision row INSERT by S2 may have happened after the first S1 SELECT.
+               // http://dev.mysql.com/doc/refman/5.0/en/set-transaction.html#isolevel_repeatable-read.
+               $flags = ( $this->mDataLoadedFrom == self::DATA_FOR_UPDATE ) ? Revision::LOCKING_READ : 0;
+               $revision = Revision::newFromPageId( $this->getId(), $latest, $flags );
                if ( $revision ) { // sanity
                        $this->setLastEdit( $revision );
                }