Fixed assertion Assertion `!table->pos_in_locked_tables' failed

MDEV-17717
Assertion `!table->pos_in_locked_tables' failed in tc_release_table on
flushing RocksDB table under SERIALIZABLE
MDEV-17998
Deadlock and eventual Assertion `!table->pos_in_locked_tables' failed
in tc_release_table on KILL_TIMEOUT
MDEV-19591
Assertion `!table->pos_in_locked_tables' failed in tc_release_table upon
altering table into S3 under lock.

The problem was that thd->open_tables->pos_in_locked_tables was not reset
when alter table failed to reopen a locked table.

mysql-test/r/kill.result

@@ -399,3 +399,20 @@ DROP USER u1@localhost;
 SET DEBUG_SYNC = 'RESET';
 DROP FUNCTION MY_KILL;
 set global sql_mode=default;
+#
+# MDEV-17998
+# Deadlock and eventual Assertion `!table->pos_in_locked_tables' failed
+# in tc_release_table on KILL_TIMEOUT
+#
+SET max_statement_time= 2;
+CREATE TABLE t1 (a INT);
+CREATE VIEW v1 AS SELECT * FROM t1;
+CREATE TABLE t2 (b INT, c INT);
+LOCK TABLES v1 READ, t2 WRITE, t1 WRITE;
+ALTER TABLE t1 CHANGE f1 f2 DOUBLE;
+Got one of the listed errors
+ALTER TABLE t2 DROP c;
+ERROR 70100: Query execution was interrupted (max_statement_time exceeded)
+UNLOCK TABLES;
+DROP VIEW v1;
+DROP TABLE t1, t2;

mysql-test/t/kill.test

@@ -642,3 +642,24 @@ SET DEBUG_SYNC = 'RESET';
 DROP FUNCTION MY_KILL;
 
 set global sql_mode=default;
+
+--echo #
+--echo # MDEV-17998
+--echo # Deadlock and eventual Assertion `!table->pos_in_locked_tables' failed
+--echo # in tc_release_table on KILL_TIMEOUT
+--echo #
+
+SET max_statement_time= 2;
+
+CREATE TABLE t1 (a INT);
+CREATE VIEW v1 AS SELECT * FROM t1;
+CREATE TABLE t2 (b INT, c INT);
+ 
+LOCK TABLES v1 READ, t2 WRITE, t1 WRITE;
+--error ER_BAD_FIELD_ERROR,ER_STATEMENT_TIMEOUT
+ALTER TABLE t1 CHANGE f1 f2 DOUBLE;
+--error ER_STATEMENT_TIMEOUT
+ALTER TABLE t2 DROP c;
+UNLOCK TABLES;
+DROP VIEW v1;
+DROP TABLE t1, t2;

sql/sql_base.cc

@@ -2371,6 +2371,7 @@ unlink_all_closed_tables(THD *thd, MYSQL_LOCK *lock, size_t reopen_count)
       DBUG_ASSERT(thd->open_tables == m_reopen_array[reopen_count]);
 
       thd->open_tables->pos_in_locked_tables->table= NULL;
+      thd->open_tables->pos_in_locked_tables= 0;
 
       close_thread_table(thd, &thd->open_tables);
     }

storage/rocksdb/mysql-test/rocksdb/r/kill.result

+CREATE TABLE t1 (pk INT PRIMARY KEY) ENGINE=RocksDB;
+LOCK TABLE t1 WRITE;
+SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
+FLUSH TABLES;
+ERROR HY000: MyRocks supports only READ COMMITTED and REPEATABLE READ isolation levels. Please change from current isolation level SERIALIZABLE
+DROP TABLE t1;

storage/rocksdb/mysql-test/rocksdb/t/kill.test

+--source include/have_binlog_format_row.inc
+--source include/have_rocksdb.inc
+
+CREATE TABLE t1 (pk INT PRIMARY KEY) ENGINE=RocksDB;
+LOCK TABLE t1 WRITE;
+SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
+--error ER_ISOLATION_MODE_NOT_SUPPORTED
+FLUSH TABLES;
+DROP TABLE t1;