2 files changed, 78 insertions, 2 deletions
diff --git a/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result b/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result
index 3670f8f1711..724f6167ce1 100644
--- a/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result
+++ b/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result
@@ -232,7 +232,6 @@ set debug_sync= "now WAIT_FOR got_no_such_table TIMEOUT 1";
 set global debug_dbug= @saved_dbug;
 drop table t1;
 set debug_sync=reset;
-SET GLOBAL innodb_purge_rseg_truncate_frequency = @saved_frequency;
 #
 # MDEV-18546 ASAN heap-use-after-free
 # in innobase_get_computed_value / row_purge
@@ -277,3 +276,32 @@ pk	b	v
 DROP TABLE t1;
 SET debug_sync= reset;
 set global debug_dbug= @old_dbug;
+# MDEV-16962 Assertion '!error || !ot_ctx.can_recover_from_failed_open()'
+# failed in open_purge_table upon concurrent ALTER and FLUSH
+CREATE TABLE t1 (
+pk SERIAL,
+c VARCHAR(128),
+d DATE,
+vd DATE AS (d) VIRTUAL,
+PRIMARY KEY(pk),
+KEY(vd,c)
+) ENGINE=InnoDB;
+INSERT IGNORE INTO t1 (pk,c) VALUES (1,'foo');
+set debug_sync="now WAIT_FOR purge";
+connect  con1,localhost,root,,test;
+SET GLOBAL innodb_debug_sync="after_open_table_mdl_shared SIGNAL purge WAIT_FOR flush";
+SET global debug_dbug="d,ib_purge_virtual_index_callback";
+REPLACE INTO t1 (pk,c) VALUES (1,'bar');
+connection default;
+SET debug_sync="alter_table_before_rename_result_table WAIT_FOR flush";
+ALTER TABLE t1 ADD FULLTEXT KEY(c), ALGORITHM=COPY;
+connection con1;
+SET debug_sync="after_flush_unlock SIGNAL flush ";
+FLUSH TABLES;
+disconnect con1;
+connection default;
+InnoDB		0 transactions not purged
+DROP TABLE t1;
+SET debug_sync= reset;
+SET global debug_dbug=@old_dbug;
+SET GLOBAL innodb_purge_rseg_truncate_frequency = @saved_frequency;
diff --git a/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test b/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test
index 3716d7e7083..a40e788f9a7 100644
--- a/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test
+++ b/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test
@@ -322,7 +322,6 @@ drop table t1;
 
 --source include/wait_until_count_sessions.inc
 set debug_sync=reset;
-SET GLOBAL innodb_purge_rseg_truncate_frequency = @saved_frequency;
 
 --echo #
 --echo # MDEV-18546 ASAN heap-use-after-free
@@ -386,3 +385,52 @@ SELECT * FROM t1;
 DROP TABLE t1;
 SET debug_sync= reset;
 set global debug_dbug= @old_dbug;
+
+
+--echo # MDEV-16962 Assertion '!error || !ot_ctx.can_recover_from_failed_open()'
+--echo # failed in open_purge_table upon concurrent ALTER and FLUSH
+
+CREATE TABLE t1 (
+  pk SERIAL,
+  c VARCHAR(128),
+  d DATE,
+  vd DATE AS (d) VIRTUAL,
+  PRIMARY KEY(pk),
+  KEY(vd,c)
+) ENGINE=InnoDB;
+INSERT IGNORE INTO t1 (pk,c) VALUES (1,'foo');
+
+--send
+set debug_sync="now WAIT_FOR purge";
+--connect (con1,localhost,root,,test)
+# Will break innodb purge thread inside open_purge_table after mdl
+# acquired, but before tdc->flushed check
+SET GLOBAL innodb_debug_sync="after_open_table_mdl_shared SIGNAL purge WAIT_FOR flush";
+
+# Workaround to pass trx_undo_roll_ptr_is_insert() in 10.2
+SET global debug_dbug="d,ib_purge_virtual_index_callback";
+
+REPLACE INTO t1 (pk,c) VALUES (1,'bar');
+
+--connection default
+# wait for MDL acquired by purge
+--reap
+# MDL_SHARED will be acquired, but will hang before MDL upgrade started.
+SET debug_sync="alter_table_before_rename_result_table WAIT_FOR flush";
+--send
+ALTER TABLE t1 ADD FULLTEXT KEY(c), ALGORITHM=COPY;
+--connection con1
+# Will hang after tdc->flushed is set, but before emptying tdc cache.
+SET debug_sync="after_flush_unlock SIGNAL flush ";
+FLUSH TABLES;
+
+# Cleanup
+--disconnect con1
+--connection default
+--reap
+--source ../../innodb/include/wait_all_purged.inc
+DROP TABLE t1;
+SET debug_sync= reset;
+SET global debug_dbug=@old_dbug;
+
+SET GLOBAL innodb_purge_rseg_truncate_frequency = @saved_frequency;