Merge branch '10.1' into 10.2mariadb-10.2.32

10 files changed, 526 insertions, 7 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 99120f16d4c..097d79fa5e7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -144,8 +144,6 @@ INCLUDE(mysql_version)
 INCLUDE(cpack_source_ignore_files)
 INCLUDE(install_layout)
 INCLUDE(wsrep)
-INCLUDE(cpack_rpm)
-INCLUDE(cpack_deb)
 
 # Add macros
 INCLUDE(character_sets)
@@ -390,6 +388,9 @@ IF(WITH_UNIT_TESTS)
  ENDIF()
 ENDIF()
 
+INCLUDE(cpack_rpm)
+INCLUDE(cpack_deb)
+
 SET (MYSQLD_STATIC_PLUGIN_LIBS "" CACHE INTERNAL "")
 
 INCLUDE(submodules)
diff --git a/cmake/cpack_rpm.cmake b/cmake/cpack_rpm.cmake
index 10e18a1894a..827b1e166a4 100644
--- a/cmake/cpack_rpm.cmake
+++ b/cmake/cpack_rpm.cmake
@@ -227,6 +227,14 @@ ELSEIF(RPM MATCHES "fedora" OR RPM MATCHES "(rhel|centos)7")
   ALTERNATIVE_NAME("test"   "mariadb-test")
 ELSEIF(RPM MATCHES "(rhel|centos)8")
   SET(PYTHON_SHEBANG "/usr/bin/python3")
+ELSEIF(RPM MATCHES "sles")
+  ALTERNATIVE_NAME("server" "mariadb")
+  SETA(CPACK_RPM_server_PACKAGE_PROVIDES
+    "mysql = %{version}-%{release}"
+    "mariadb_${MAJOR_VERSION}${MINOR_VERSION} = %{version}-%{release}"
+    "mariadb-${MAJOR_VERSION}${MINOR_VERSION} = %{version}-%{release}"
+    "mariadb-server = %{version}-%{release}"
+  )
 ENDIF()
 
 # If we want to build build MariaDB-shared-compat,
diff --git a/mysql-test/r/processlist_notembedded.result b/mysql-test/r/processlist_notembedded.result
index 67eeb5ae2ff..e663c407a1b 100644
--- a/mysql-test/r/processlist_notembedded.result
+++ b/mysql-test/r/processlist_notembedded.result
@@ -3,10 +3,11 @@
 #
 connect  con1,localhost,root,,;
 connection con1;
-SET DEBUG_SYNC= 'before_join_optimize SIGNAL in_sync';
+SET DEBUG_SYNC= 'before_join_optimize SIGNAL in_sync WAIT_FOR go';
 connection default;
 SET DEBUG_SYNC= 'now WAIT_FOR in_sync';
-FOUND 1 /sleep \(30\)/ in MDEV-20466.text
+FOUND 1 /sleep/ in MDEV-20466.text
+SET DEBUG_SYNC= 'now SIGNAL go';
 disconnect con1;
 SET DEBUG_SYNC = 'RESET';
 End of 5.5 tests
diff --git a/mysql-test/suite/innodb/r/foreign_key.result b/mysql-test/suite/innodb/r/foreign_key.result
index d1a5016d429..b0b4635157e 100644
--- a/mysql-test/suite/innodb/r/foreign_key.result
+++ b/mysql-test/suite/innodb/r/foreign_key.result
@@ -209,6 +209,7 @@ ERROR 70100: Query execution was interrupted
 connection con1;
 ROLLBACK;
 connection default;
+disconnect con1;
 DROP TABLE t3,t1;
 #
 # MDEV-18222 InnoDB: Failing assertion: heap->magic_n == MEM_BLOCK_MAGIC_N
@@ -291,6 +292,121 @@ ALTER TABLE t1 DROP f3;
 ALTER TABLE t1 CHANGE f f3 INT;
 DROP TABLE t1;
 SET FOREIGN_KEY_CHECKS=1;
+#
+# Bug #19471516 SERVER CRASHES WHEN EXECUTING ALTER TABLE
+# ADD FOREIGN KEY
+#
+CREATE TABLE `department` (`department_id` INT, `department_people_fk` INT,
+PRIMARY KEY (`department_id`)) engine=innodb;
+CREATE TABLE `title` (`title_id` INT, `title_manager_fk` INT,
+`title_reporter_fk` INT, PRIMARY KEY (`title_id`)) engine=innodb;
+CREATE TABLE `people` (`people_id` INT, PRIMARY KEY (`people_id`)) engine=innodb;
+ALTER TABLE `department` ADD FOREIGN KEY (`department_people_fk`) REFERENCES
+`people` (`people_id`);
+ALTER TABLE `title` ADD FOREIGN KEY (`title_manager_fk`) REFERENCES `people`
+(`people_id`);
+ALTER TABLE `title` ADD FOREIGN KEY (`title_reporter_fk`) REFERENCES `people`
+(`people_id`);
+drop table title, department, people;
+create table t1 (a int primary key, b int) engine=innodb;
+create table t2 (c int primary key, d int,
+foreign key (d) references t1 (a) on update cascade) engine=innodb;
+insert t1 values (1,1),(2,2),(3,3);
+insert t2 values (4,1),(5,2),(6,3);
+flush table t2 with read lock;
+connect  con1,localhost,root;
+delete from t1 where a=2;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`t2`, CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`d`) REFERENCES `t1` (`a`) ON UPDATE CASCADE)
+update t1 set a=10 where a=1;
+connection default;
+unlock tables;
+connection con1;
+connection default;
+lock table t2 write;
+connection con1;
+delete from t1 where a=2;
+connection default;
+unlock tables;
+connection con1;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`t2`, CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`d`) REFERENCES `t1` (`a`) ON UPDATE CASCADE)
+connection default;
+unlock tables;
+disconnect con1;
+create user foo;
+grant select,update on test.t1 to foo;
+connect foo,localhost,foo;
+update t1 set a=30 where a=3;
+disconnect foo;
+connection default;
+select * from t2;
+c	d
+5	2
+4	10
+6	30
+drop table t2, t1;
+drop user foo;
+#
+# MDEV-17595 - Server crashes in copy_data_between_tables or
+#              Assertion `thd->transaction.stmt.is_empty() ||
+#              (thd->state_flags & Open_tables_state::BACKUPS_AVAIL)'
+#              fails in close_tables_for_reopen upon concurrent
+#              ALTER TABLE and FLUSH
+#
+CREATE TABLE t1 (a INT, KEY(a)) ENGINE=InnoDB;
+INSERT INTO t1 VALUES(1),(2);
+CREATE TABLE t2 (b INT, KEY(b)) ENGINE=InnoDB;
+INSERT INTO t2 VALUES(2);
+ALTER TABLE t2 ADD FOREIGN KEY(b) REFERENCES t1(a), LOCK=EXCLUSIVE;
+DROP TABLE t2, t1;
+create table t1 (pk int primary key, data int) engine=innodb;
+insert t1 values (1,1),(2,2),(3,3);
+create table t2 (t1_pk int, foreign key (t1_pk) references t1 (pk)) engine=innodb;
+insert t2 values (1),(2);
+insert t2 values (10);
+ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (`test`.`t2`, CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`t1_pk`) REFERENCES `t1` (`pk`))
+flush tables;
+flush status;
+update t1 set data=10 where pk+1>10;
+show status like '%opened_tab%';
+Variable_name	Value
+Opened_table_definitions	1
+Opened_tables	1
+flush tables;
+flush status;
+update t2 set t1_pk=11 where t1_pk+1>10;
+show status like '%opened_tab%';
+Variable_name	Value
+Opened_table_definitions	1
+Opened_tables	1
+flush tables;
+flush status;
+lock tables t1 write;
+show status like '%opened_tab%';
+Variable_name	Value
+Opened_table_definitions	2
+Opened_tables	2
+insert t1 values (4,4);
+show status like '%opened_tab%';
+Variable_name	Value
+Opened_table_definitions	2
+Opened_tables	2
+unlock tables;
+create function foo() returns int
+begin
+insert t1 values (5,5);
+return 5;
+end|
+flush tables;
+flush status;
+select foo();
+foo()
+5
+show status like '%opened_tab%';
+Variable_name	Value
+Opened_table_definitions	2
+Opened_tables	2
+drop function foo;
+drop table t2, t1;
 # Start of 10.2 tests
 #
 # MDEV-13246 Stale rows despite ON DELETE CASCADE constraint
@@ -328,6 +444,7 @@ INSERT INTO matchmaking_group_users VALUES (10,1),(11,2);
 INSERT INTO matchmaking_group_maps VALUES (10,55),(11,66);
 BEGIN;
 UPDATE users SET name = 'qux' WHERE id = 1;
+connect  con1,localhost,root;
 connection con1;
 SET innodb_lock_wait_timeout= 1;
 DELETE FROM matchmaking_groups WHERE id = 10;
@@ -538,4 +655,63 @@ Table	Op	Msg_type	Msg_text
 test.t1	check	status	OK
 DROP TABLE t1;
 SET GLOBAL innodb_purge_rseg_truncate_frequency = @saved_frequency;
+#
+# MDEV-17187 table doesn't exist in engine after ALTER other tables
+# with CONSTRAINTs
+#
+set foreign_key_checks=on;
+create table t1 (id int not null primary key) engine=innodb;
+create table t2 (id int not null primary key, fid int not null,
+CONSTRAINT fk_fid FOREIGN KEY (fid) REFERENCES t1 (id))engine=innodb;
+insert into t1 values (1), (2), (3);
+insert into t2 values (1, 1), (2, 1), (3, 2);
+set foreign_key_checks=off;
+alter table t2 drop index fk_fid;
+set foreign_key_checks=on;
+delete from t1 where id=2;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`t2`, CONSTRAINT `fk_fid` FOREIGN KEY (`fid`) REFERENCES `t1` (`id`))
+insert into t2 values(4, 99);
+ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (`test`.`t2`, CONSTRAINT `fk_fid` FOREIGN KEY (`fid`) REFERENCES `t1` (`id`))
+select * from t1;
+id
+1
+2
+3
+select * from t2;
+id	fid
+1	1
+2	1
+3	2
+set foreign_key_checks=off;
+delete from t1 where id=2;
+insert into t2 values(4, 99);
+set foreign_key_checks=on;
+select * from t1;
+id
+1
+3
+select * from t2;
+id	fid
+1	1
+2	1
+3	2
+4	99
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `id` int(11) NOT NULL,
+  PRIMARY KEY (`id`)
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `id` int(11) NOT NULL,
+  `fid` int(11) NOT NULL,
+  PRIMARY KEY (`id`),
+  CONSTRAINT `fk_fid` FOREIGN KEY (`fid`) REFERENCES `t1` (`id`)
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+drop table t1,t2;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails
+drop table t1,t2;
+ERROR 42S02: Unknown table 'test.t2'
 # End of 10.2 tests
diff --git a/mysql-test/suite/innodb/r/foreign_key_debug.result b/mysql-test/suite/innodb/r/foreign_key_debug.result
new file mode 100644
index 00000000000..741200b62b2
--- /dev/null
+++ b/mysql-test/suite/innodb/r/foreign_key_debug.result
@@ -0,0 +1,60 @@
+create table t1 (f1 int primary key) engine=innodb;
+create table t2 (f2 int primary key) engine=innodb;
+create table t3 (f3 int primary key, foreign key (f3) references t2(f2)) engine=innodb;
+insert into t1 values (1),(2),(3),(4),(5);
+insert into t2 values (1),(2),(3),(4),(5);
+insert into t3 values (1),(2),(3),(4),(5);
+connect con1,localhost,root;
+set debug_sync='alter_table_before_rename_result_table signal g1 wait_for g2';
+alter table t2 add constraint foreign key (f2) references t1(f1) on delete cascade on update cascade;
+connection default;
+set debug_sync='before_execute_sql_command wait_for g1';
+update t1 set f1 = f1 + 100000 limit 2;
+connect con2,localhost,root;
+kill query UPDATE;
+disconnect con2;
+connection default;
+ERROR 70100: Query execution was interrupted
+set debug_sync='now signal g2';
+connection con1;
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `f2` int(11) NOT NULL,
+  PRIMARY KEY (`f2`),
+  CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`f2`) REFERENCES `t1` (`f1`) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+disconnect con1;
+connection default;
+select * from t2 where f2 not in (select f1 from t1);
+f2
+select * from t3 where f3 not in (select f2 from t2);
+f3
+drop table t3;
+drop table t2;
+drop table t1;
+set debug_sync='reset';
+#
+# MDEV-16060 - InnoDB: Failing assertion: ut_strcmp(index->name, key->name)
+#
+CREATE TABLE t1 (`pk` INT PRIMARY KEY) ENGINE=InnoDB;
+CREATE TABLE t2 LIKE t1;
+FLUSH TABLES;
+SET debug_sync='alter_table_intermediate_table_created SIGNAL ready WAIT_FOR go';
+ALTER TABLE t1 ADD FOREIGN KEY(pk) REFERENCES t2(pk) ON UPDATE CASCADE;
+connect con1, localhost, root;
+SET debug_sync='now WAIT_FOR ready';
+SET lock_wait_timeout=1;
+UPDATE t2 SET pk=10 WHERE pk=1;
+ERROR HY000: Lock wait timeout exceeded; try restarting transaction
+PREPARE stmt FROM 'UPDATE t2 SET pk=10 WHERE pk=1';
+DEALLOCATE PREPARE stmt;
+FLUSH TABLE t2;
+SET debug_sync='now SIGNAL go';
+connection default;
+disconnect con1;
+connection default;
+SET debug_sync='reset';
+SHOW OPEN TABLES FROM test;
+Database	Table	In_use	Name_locked
+DROP TABLE t1, t2;
diff --git a/mysql-test/suite/innodb/t/foreign_key.test b/mysql-test/suite/innodb/t/foreign_key.test
index 13203383188..27fa63f144e 100644
--- a/mysql-test/suite/innodb/t/foreign_key.test
+++ b/mysql-test/suite/innodb/t/foreign_key.test
@@ -195,6 +195,7 @@ reap;
 connection con1;
 ROLLBACK;
 connection default;
+disconnect con1;
 
 DROP TABLE t3,t1;
 
@@ -281,6 +282,136 @@ DROP TABLE t1;
 
 SET FOREIGN_KEY_CHECKS=1;
 
+--echo #
+--echo # Bug #19471516 SERVER CRASHES WHEN EXECUTING ALTER TABLE
+--echo # ADD FOREIGN KEY
+--echo #
+
+CREATE TABLE `department` (`department_id` INT, `department_people_fk` INT,
+PRIMARY KEY (`department_id`)) engine=innodb;
+
+CREATE TABLE `title` (`title_id` INT, `title_manager_fk` INT,
+`title_reporter_fk` INT, PRIMARY KEY (`title_id`)) engine=innodb;
+
+CREATE TABLE `people` (`people_id` INT, PRIMARY KEY (`people_id`)) engine=innodb;
+
+ALTER TABLE `department` ADD FOREIGN KEY (`department_people_fk`) REFERENCES
+`people` (`people_id`);
+
+ALTER TABLE `title` ADD FOREIGN KEY (`title_manager_fk`) REFERENCES `people`
+(`people_id`);
+
+ALTER TABLE `title` ADD FOREIGN KEY (`title_reporter_fk`) REFERENCES `people`
+(`people_id`);
+
+drop table title, department, people;
+
+#
+# FK and prelocking:
+# child table accesses (reads and writes) wait for locks.
+#
+create table t1 (a int primary key, b int) engine=innodb;
+create table t2 (c int primary key, d int,
+  foreign key (d) references t1 (a) on update cascade) engine=innodb;
+insert t1 values (1,1),(2,2),(3,3);
+insert t2 values (4,1),(5,2),(6,3);
+flush table t2 with read lock; # this takes MDL_SHARED_NO_WRITE
+connect (con1,localhost,root);
+--error ER_ROW_IS_REFERENCED_2
+delete from t1 where a=2;
+send update t1 set a=10 where a=1;
+connection default;
+let $wait_condition= select 1 from information_schema.processlist where state='Waiting for table metadata lock';
+source include/wait_condition.inc;
+unlock tables;
+connection con1;
+reap;
+connection default;
+lock table t2 write; # this takes MDL_SHARED_NO_READ_WRITE
+connection con1;
+send delete from t1 where a=2;
+connection default;
+let $wait_condition= select 1 from information_schema.processlist where state='Waiting for table metadata lock';
+source include/wait_condition.inc;
+unlock tables;
+connection con1;
+--error ER_ROW_IS_REFERENCED_2
+reap;
+connection default;
+unlock tables;
+disconnect con1;
+
+# but privileges should not be checked
+create user foo;
+grant select,update on test.t1 to foo;
+connect(foo,localhost,foo);
+update t1 set a=30 where a=3;
+disconnect foo;
+connection default;
+select * from t2;
+drop table t2, t1;
+drop user foo;
+
+--echo #
+--echo # MDEV-17595 - Server crashes in copy_data_between_tables or
+--echo #              Assertion `thd->transaction.stmt.is_empty() ||
+--echo #              (thd->state_flags & Open_tables_state::BACKUPS_AVAIL)'
+--echo #              fails in close_tables_for_reopen upon concurrent
+--echo #              ALTER TABLE and FLUSH
+--echo #
+CREATE TABLE t1 (a INT, KEY(a)) ENGINE=InnoDB;
+INSERT INTO t1 VALUES(1),(2);
+CREATE TABLE t2 (b INT, KEY(b)) ENGINE=InnoDB;
+INSERT INTO t2 VALUES(2);
+ALTER TABLE t2 ADD FOREIGN KEY(b) REFERENCES t1(a), LOCK=EXCLUSIVE;
+DROP TABLE t2, t1;
+
+#
+# MDEV-22180 Planner opens unnecessary tables when updated table is referenced by foreign keys
+#
+
+create table t1 (pk int primary key, data int) engine=innodb;
+insert t1 values (1,1),(2,2),(3,3);
+create table t2 (t1_pk int, foreign key (t1_pk) references t1 (pk)) engine=innodb;
+insert t2 values (1),(2);
+error ER_NO_REFERENCED_ROW_2;
+insert t2 values (10);
+flush tables;
+flush status;
+# with ON UPDATE RESTRICT child tables are not opened
+update t1 set data=10 where pk+1>10;
+show status like '%opened_tab%';
+flush tables;
+flush status;
+# neither are parent tables
+update t2 set t1_pk=11 where t1_pk+1>10;
+show status like '%opened_tab%';
+# under LOCK TABLES
+flush tables;
+flush status;
+lock tables t1 write;
+show status like '%opened_tab%';
+insert t1 values (4,4);
+show status like '%opened_tab%';
+unlock tables;
+delimiter |;
+create function foo() returns int
+begin
+  insert t1 values (5,5);
+  return 5;
+end|
+delimiter ;|
+flush tables;
+flush status;
+select foo();
+show status like '%opened_tab%';
+drop function foo;
+drop table t2, t1;
+
+#
+# End of 10.1 tests
+#
+
 --echo # Start of 10.2 tests
 
 --echo #
@@ -326,6 +457,7 @@ INSERT INTO matchmaking_group_maps VALUES (10,55),(11,66);
 BEGIN;
 UPDATE users SET name = 'qux' WHERE id = 1;
 
+connect (con1,localhost,root);
 --connection con1
 SET innodb_lock_wait_timeout= 1;
 DELETE FROM matchmaking_groups WHERE id = 10;
@@ -520,6 +652,52 @@ CHECK TABLE t1;
 DROP TABLE t1;
 SET GLOBAL innodb_purge_rseg_truncate_frequency = @saved_frequency;
 
+--echo #
+--echo # MDEV-17187 table doesn't exist in engine after ALTER other tables
+--echo # with CONSTRAINTs
+--echo #
+
+set foreign_key_checks=on;
+create table t1 (id int not null primary key) engine=innodb;
+create table t2 (id int not null primary key, fid int not null,
+CONSTRAINT fk_fid FOREIGN KEY (fid) REFERENCES t1 (id))engine=innodb;
+
+insert into t1 values (1), (2), (3);
+insert into t2 values (1, 1), (2, 1), (3, 2);
+
+set foreign_key_checks=off;
+alter table t2 drop index fk_fid;
+set foreign_key_checks=on;
+
+--error ER_ROW_IS_REFERENCED_2
+delete from t1 where id=2;
+--error ER_NO_REFERENCED_ROW_2
+insert into t2 values(4, 99);
+
+select * from t1;
+select * from t2;
+
+set foreign_key_checks=off;
+delete from t1 where id=2;
+insert into t2 values(4, 99);
+set foreign_key_checks=on;
+
+select * from t1;
+select * from t2;
+
+show create table t1;
+show create table t2;
+
+# Optional: test DROP TABLE without any prior ha_innobase::open().
+# This was tested manually, but it would cause --embedded to skip the test,
+# and the restart would significantly increase the running time.
+# --source include/restart_mysqld.inc
+
+--error ER_ROW_IS_REFERENCED_2
+drop table t1,t2;
+--error ER_BAD_TABLE_ERROR
+drop table t1,t2;
+
 --echo # End of 10.2 tests
 
 --source include/wait_until_count_sessions.inc
diff --git a/mysql-test/suite/innodb/t/foreign_key_debug.test b/mysql-test/suite/innodb/t/foreign_key_debug.test
new file mode 100644
index 00000000000..75d05801b5f
--- /dev/null
+++ b/mysql-test/suite/innodb/t/foreign_key_debug.test
@@ -0,0 +1,78 @@
+--source include/have_innodb.inc
+--source include/have_debug.inc
+--source include/have_debug_sync.inc
+
+--enable_connect_log
+
+#
+# MDEV-16465 Invalid (old?) table or database name or hang in ha_innobase::delete_table and log semaphore wait upon concurrent DDL with foreign keys
+#
+create table t1 (f1 int primary key) engine=innodb;
+create table t2 (f2 int primary key) engine=innodb;
+create table t3 (f3 int primary key, foreign key (f3) references t2(f2)) engine=innodb;
+insert into t1 values (1),(2),(3),(4),(5);
+insert into t2 values (1),(2),(3),(4),(5);
+insert into t3 values (1),(2),(3),(4),(5);
+connect con1,localhost,root;
+set debug_sync='alter_table_before_rename_result_table signal g1 wait_for g2';
+send alter table t2 add constraint foreign key (f2) references t1(f1) on delete cascade on update cascade;
+connection default;
+let $conn=`select connection_id()`;
+set debug_sync='before_execute_sql_command wait_for g1';
+send update t1 set f1 = f1 + 100000 limit 2;
+connect con2,localhost,root;
+let $wait_condition= select 1 from information_schema.processlist where state='Waiting for table metadata lock' and info like 'update t1 %';
+source include/wait_condition.inc;
+--replace_result $conn UPDATE
+eval kill query $conn;
+disconnect con2;
+connection default;
+error ER_QUERY_INTERRUPTED;
+reap;
+set debug_sync='now signal g2';
+connection con1;
+reap;
+show create table t2;
+disconnect con1;
+connection default;
+select * from t2 where f2 not in (select f1 from t1);
+select * from t3 where f3 not in (select f2 from t2);
+drop table t3;
+drop table t2;
+drop table t1;
+set debug_sync='reset';
+
+--echo #
+--echo # MDEV-16060 - InnoDB: Failing assertion: ut_strcmp(index->name, key->name)
+--echo #
+CREATE TABLE t1 (`pk` INT PRIMARY KEY) ENGINE=InnoDB;
+CREATE TABLE t2 LIKE t1;
+FLUSH TABLES;
+
+SET debug_sync='alter_table_intermediate_table_created SIGNAL ready WAIT_FOR go';
+send ALTER TABLE t1 ADD FOREIGN KEY(pk) REFERENCES t2(pk) ON UPDATE CASCADE;
+
+connect con1, localhost, root;
+SET debug_sync='now WAIT_FOR ready';
+SET lock_wait_timeout=1; # change to 0 in 10.3
+--error ER_LOCK_WAIT_TIMEOUT
+UPDATE t2 SET pk=10 WHERE pk=1;
+PREPARE stmt FROM 'UPDATE t2 SET pk=10 WHERE pk=1';
+DEALLOCATE PREPARE stmt;
+FLUSH TABLE t2;
+SET debug_sync='now SIGNAL go';
+
+connection default;
+reap;
+
+# Cleanup
+disconnect con1;
+
+connection default;
+SET debug_sync='reset';
+SHOW OPEN TABLES FROM test;
+DROP TABLE t1, t2;
+
+#
+# End of 10.1 tests
+#
diff --git a/mysql-test/t/processlist_notembedded.test b/mysql-test/t/processlist_notembedded.test
index 2dc6a0539ab..4979e40a85a 100644
--- a/mysql-test/t/processlist_notembedded.test
+++ b/mysql-test/t/processlist_notembedded.test
@@ -1,6 +1,7 @@
 source include/have_debug.inc;
 source include/have_debug_sync.inc;
 source include/not_embedded.inc;
+source include/count_sessions.inc;
 
 --echo #
 --echo # MDEV-20466: SHOW PROCESSLIST truncates query text on \0 bytes
@@ -10,9 +11,9 @@ connect (con1,localhost,root,,);
 
 connection con1;
 
-let $q= `select CONCAT("SELECT user FROM mysql.user WHERE user ='some", CHAR(0), "' or sleep (30)")`;
+let $q= `select CONCAT("SELECT user FROM mysql.user WHERE user ='some", CHAR(0), "sleep'")`;
 
-SET DEBUG_SYNC= 'before_join_optimize SIGNAL in_sync';
+SET DEBUG_SYNC= 'before_join_optimize SIGNAL in_sync WAIT_FOR go';
 --disable_query_log
 --send_eval $q;
 --enable_query_log
@@ -23,12 +24,16 @@ SET DEBUG_SYNC= 'now WAIT_FOR in_sync';
 exec $MYSQL test  -e "SHOW PROCESSLIST" > $MYSQLTEST_VARDIR/tmp/MDEV-20466.text;
 
 let SEARCH_FILE=$MYSQLTEST_VARDIR/tmp/MDEV-20466.text;
-let SEARCH_PATTERN=sleep \(30\);
+let SEARCH_PATTERN=sleep;
 source include/search_pattern_in_file.inc;
 remove_file $MYSQLTEST_VARDIR/tmp/MDEV-20466.text;
 
+SET DEBUG_SYNC= 'now SIGNAL go';
+
 disconnect con1;
 
 SET DEBUG_SYNC = 'RESET';
 
+source include/wait_until_count_sessions.inc;
+
 --echo End of 5.5 tests
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index f31c3f36aa8..45916220896 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -4445,10 +4445,19 @@ bool Lock_tables_prelocking_strategy::
 handle_table(THD *thd, Query_tables_list *prelocking_ctx,
              TABLE_LIST *table_list, bool *need_prelocking)
 {
+  TABLE_LIST **last= prelocking_ctx->query_tables_last;
+
   if (DML_prelocking_strategy::handle_table(thd, prelocking_ctx, table_list,
                                             need_prelocking))
     return TRUE;
 
+  /*
+    normally we don't need to open FK-prelocked tables for RESTRICT,
+    MDL is enough. But under LOCK TABLES we have to open everything
+  */
+  for (TABLE_LIST *tl= *last; tl; tl= tl->next_global)
+    tl->open_strategy= TABLE_LIST::OPEN_NORMAL;
+
   /* We rely on a caller to check that table is going to be changed. */
   DBUG_ASSERT(table_list->lock_type >= TL_WRITE_ALLOW_WRITE);
 
diff --git a/sql/table.h b/sql/table.h
index e0541ef3f2e..0cf0e4efe00 100644
--- a/sql/table.h
+++ b/sql/table.h
@@ -1818,6 +1818,9 @@ struct TABLE_LIST
     open_type= routine ? OT_TEMPORARY_OR_BASE : OT_BASE_ONLY;
     belong_to_view= belong_to_view_arg;
     trg_event_map= trg_event_map_arg;
+    /* MDL is enough for read-only FK checks, we don't need the table */
+    if (prelocking_placeholder == FK && lock_type < TL_WRITE_ALLOW_WRITE)
+      open_strategy= OPEN_STUB;
 
     **last_ptr= this;
     prev_global= *last_ptr;