[#MDEV-25483] Shutdown crash during innodb.innodb_buffer_pool_resize

The test innodb.innodb_buffer_pool_resize_temporary triggered an InnoDB crash during shutdown, leading to a situation where log-based recovery would be needed:

10.5 675c22c065110be03a5fab82442d2c3dc32aefff
CURRENT_TEST: innodb.innodb_buffer_pool_resize_temporary
Warning: /mnt/buildbot/build/mariadb-10.5.10/libmysqld/examples/mysqltest_embedded: unknown variable 'loose-ssl-ca=/mnt/buildbot/build/mariadb-10.5.10/mysql-test/std_data/cacert.pem'
Warning: /mnt/buildbot/build/mariadb-10.5.10/libmysqld/examples/mysqltest_embedded: unknown variable 'loose-ssl-cert=/mnt/buildbot/build/mariadb-10.5.10/mysql-test/std_data/client-cert.pem'
Warning: /mnt/buildbot/build/mariadb-10.5.10/libmysqld/examples/mysqltest_embedded: unknown variable 'loose-ssl-key=/mnt/buildbot/build/mariadb-10.5.10/mysql-test/std_data/client-key.pem'
Warning: /mnt/buildbot/build/mariadb-10.5.10/libmysqld/examples/mysqltest_embedded: unknown option '--loose-skip-ssl'
Got ERROR: "InnoDB: Operating system error number 2 in a file operation." errno: 2000
Got ERROR: "InnoDB: The error means the system cannot find the path specified." errno: 2000
Got ERROR: "InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them." errno: 2000
Got ERROR: "InnoDB: Cannot open datafile for read-only: './mysql/innodb_index_stats.ibd' OS error: 71" errno: 2000
Got ERROR: "InnoDB: Operating system error number 2 in a file operation." errno: 2000
Got ERROR: "InnoDB: The error means the system cannot find the path specified." errno: 2000
Got ERROR: "InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them." errno: 2000
Got ERROR: "InnoDB: Cannot open datafile for read-only: './mysql/innodb_table_stats.ibd' OS error: 71" errno: 2000
Got ERROR: "InnoDB: Operating system error number 2 in a file operation." errno: 2000
Got ERROR: "InnoDB: The error means the system cannot find the path specified." errno: 2000
Got ERROR: "InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them." errno: 2000
Got ERROR: "InnoDB: Cannot open datafile for read-only: './mysql/transaction_registry.ibd' OS error: 71" errno: 2000
2021-04-19 19:27:51 0xaf3feb40 InnoDB: Assertion failure in file /home/buildbot/buildbot/build/mariadb-10.5.10/storage/innobase/buf/buf0buf.cc line 2325
InnoDB: Failing assertion: srv_shutdown_state == SRV_SHUTDOWN_NONE
InnoDB: We intentionally generate a memory trap.

diff --git a/storage/innobase/buf/buf0buf.cc b/storage/innobase/buf/buf0buf.cc

index 2923c6d4790..0079f6582ab 100644

--- a/storage/innobase/buf/buf0buf.cc

+++ b/storage/innobase/buf/buf0buf.cc

@@ -2322,7 +2322,7 @@ inline void buf_pool_t::resize()

 static void buf_resize_callback(void *)

   DBUG_ENTER("buf_resize_callback");

-  ut_a(srv_shutdown_state == SRV_SHUTDOWN_NONE);

+  ut_ad(srv_shutdown_state < SRV_SHUTDOWN_CLEANUP);

   mysql_mutex_lock(&buf_pool.mutex);

   const auto size= srv_buf_pool_size;

   const bool work= srv_buf_pool_old_size != size;

It suffices to have an assertion in debug builds only. This test did fail in a debug build (IA-32 embedded server) after all. The shutdown state may have advanced a little already. The following in logs_empty_and_mark_files_at_shutdown() will make this work:

	buf_resize_shutdown();

	dict_stats_shutdown();

	btr_defragment_shutdown();

	srv_shutdown_state = SRV_SHUTDOWN_CLEANUP;

There is another assignment to SRV_SHUTDOWN_CLEANUP in innodb_shutdown() as a special case for mariabackup --prepare that is not preceded by such task shutdown, but in that case, the tasks should never have been started by invoking buf_resize_start() et al:

[MDEV-25483] Shutdown crash during innodb.innodb_buffer_pool_resize_temporary Created: 2021-04-22 Updated: 2021-04-22 Resolved: 2021-04-22
Status:	Closed
Project:	MariaDB Server
Component/s:	Storage Engine - InnoDB
Affects Version/s:	10.5.0, 10.5, 10.6
Fix Version/s:	10.5.10, 10.6.0

[MDEV-25483] Shutdown crash during innodb.innodb_buffer_pool_resize_temporary Created: 2021-04-22 Updated: 2021-04-22 Resolved: 2021-04-22