MDEV-24981 LOAD INDEX may cause rollback of prepared XA transaction

XAER_RMFAIL means the admin statement was not allowed, it's not a
per-table message, so must fail the whole statement. And must
not rollback, obviously, it's not allowed after prepare.

Also, remove duplicate XAER_RMFAIL in open_tables(),
check_has_uncommitted_xa() already issues it.

mysql-test/main/xa.result

@@ -1,5 +1,4 @@
 call mtr.add_suppression("Deadlock found when trying to get lock; try restarting transaction");
-drop table if exists t1, t2;
 create table t1 (a int) engine=innodb;
 xa start 'test1';
 insert t1 values (10);
@@ -595,6 +594,26 @@ formatID	gtrid_length	bqual_length	data
 xa rollback '4';
 ERROR XA100: XA_RBROLLBACK: Transaction branch was rolled back
 set @@global.read_only=@sav_read_only;
-#
 # End of 10.5 tests
 #
+# MDEV-24981 LOAD INDEX may cause rollback of prepared XA transaction
+#
+create table t1 (f1 integer primary key) engine=innodb;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `f1` int(11) NOT NULL,
+  PRIMARY KEY (`f1`)
+) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
+xa start 'a';
+insert into t1 values (1);
+xa end 'a';
+xa prepare 'a';
+load index into cache t1 key(primary);
+ERROR XAE07: XAER_RMFAIL: The command cannot be executed when global transaction is in the  PREPARED state
+xa commit 'a';
+select count(*) from t1;
+count(*)
+1
+drop table t1;
+# End of 10.11 tests

mysql-test/main/xa.test

@@ -1,7 +1,7 @@
 #
 # WL#1756
 #
--- source include/have_innodb.inc
+--source include/have_innodb.inc
 --source include/not_embedded.inc
 
 # Save the initial number of concurrent sessions
@@ -12,10 +12,6 @@ call mtr.add_suppression("Deadlock found when trying to get lock; try restarting
 call mtr.add_suppression("InnoDB: Transaction was aborted due to ");
 --enable_query_log
 
-
---disable_warnings
-drop table if exists t1, t2;
---enable_warnings
 create table t1 (a int) engine=innodb;
 xa start 'test1';
 insert t1 values (10);
@@ -752,7 +748,21 @@ xa rollback '4';
 
 set @@global.read_only=@sav_read_only;
 
+--echo # End of 10.5 tests
 
 --echo #
---echo # End of 10.5 tests
+--echo # MDEV-24981 LOAD INDEX may cause rollback of prepared XA transaction
 --echo #
+create table t1 (f1 integer primary key) engine=innodb;
+show create table t1;
+xa start 'a';
+insert into t1 values (1);
+xa end 'a';
+xa prepare 'a';
+--error ER_XAER_RMFAIL
+load index into cache t1 key(primary);
+xa commit 'a';
+select count(*) from t1;
+drop table t1;
+
+--echo # End of 10.11 tests

sql/sql_admin.cc

@@ -565,6 +565,9 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
   Disable_wsrep_on_guard wsrep_on_guard(thd, disable_wsrep_on);
 #endif /* WITH_WSREP */
 
+  if (thd->transaction->xid_state.check_has_uncommitted_xa())
+    DBUG_RETURN(TRUE);
+
   fill_check_table_metadata_fields(thd, &field_list);
 
   if (protocol->send_result_set_metadata(&field_list,

sql/sql_base.cc

@@ -4598,10 +4598,7 @@ bool open_tables(THD *thd, const DDL_options_st &options,
     if (!table->schema_table)
     {
       if (thd->transaction->xid_state.check_has_uncommitted_xa())
-      {
-	thd->transaction->xid_state.er_xaer_rmfail();
         DBUG_RETURN(true);
-      }
       else
         break;
     }