diff --git a/mysql-test/suite/innodb/r/innodb-blob.result b/mysql-test/suite/innodb/r/innodb-blob.result
index 8173d30e92c..0be1ca5b938 100644
--- a/mysql-test/suite/innodb/r/innodb-blob.result
+++ b/mysql-test/suite/innodb/r/innodb-blob.result
@@ -20,8 +20,6 @@ a	RIGHT(b,20)
 2	bbbbbbbbbbbbbbbbbbbb
 connection default;
 SET DEBUG='+d,row_ins_extern_checkpoint';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 SET DEBUG_SYNC='before_row_ins_extern_latch SIGNAL rec_not_blob WAIT_FOR crash';
 ROLLBACK;
 BEGIN;
@@ -88,8 +86,6 @@ BEGIN;
 INSERT INTO t2 VALUES (347);
 connection default;
 SET DEBUG='+d,row_upd_extern_checkpoint';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 SET DEBUG_SYNC='before_row_upd_extern SIGNAL have_latch WAIT_FOR crash';
 UPDATE t3 SET c=REPEAT('i',3000) WHERE a=2;
 connection con2;
@@ -126,8 +122,6 @@ BEGIN;
 INSERT INTO t2 VALUES (33101);
 connection default;
 SET DEBUG='+d,row_upd_extern_checkpoint';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 SET DEBUG_SYNC='after_row_upd_extern SIGNAL have_latch WAIT_FOR crash';
 UPDATE t3 SET c=REPEAT('j',3000) WHERE a=2;
 connection con2;
diff --git a/mysql-test/suite/innodb/r/innodb-index-debug.result b/mysql-test/suite/innodb/r/innodb-index-debug.result
index 0995b526821..7167a80f3cb 100644
--- a/mysql-test/suite/innodb/r/innodb-index-debug.result
+++ b/mysql-test/suite/innodb/r/innodb-index-debug.result
@@ -92,8 +92,6 @@ ALTER TABLE t1 FORCE, ADD COLUMN k4 int;
 connection default;
 SET DEBUG_SYNC= 'now WAIT_FOR opened';
 SET debug = '+d,row_log_tmpfile_fail';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 INSERT INTO t1 select NULL,'aaa','bbb' from t480;
 INSERT INTO t1 select NULL,'aaaa','bbbb' from t480;
 SET DEBUG_SYNC= 'now SIGNAL flushed';
diff --git a/mysql-test/suite/innodb/r/innodb-table-online.result b/mysql-test/suite/innodb/r/innodb-table-online.result
index 9296fded0fd..de42ecd7979 100644
--- a/mysql-test/suite/innodb/r/innodb-table-online.result
+++ b/mysql-test/suite/innodb/r/innodb-table-online.result
@@ -38,16 +38,10 @@ SET DEBUG_DBUG = '+d,innodb_OOM_prepare_inplace_alter';
 ALTER TABLE t1 ROW_FORMAT=REDUNDANT, ALGORITHM=INPLACE, LOCK=NONE;
 ERROR HY000: Out of memory.
 SET SESSION DEBUG = @saved_debug_dbug;
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 SET SESSION DEBUG = '+d,innodb_OOM_inplace_alter';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 ALTER TABLE t1 ROW_FORMAT=REDUNDANT, ALGORITHM=INPLACE, LOCK=NONE;
 ERROR HY000: Out of memory.
 SET SESSION DEBUG = @saved_debug_dbug;
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 ALTER TABLE t1 ROW_FORMAT=REDUNDANT, ALGORITHM=INPLACE, LOCK=NONE;
 connection default;
 SHOW CREATE TABLE t1;
diff --git a/mysql-test/suite/innodb/r/page_reorganize.result b/mysql-test/suite/innodb/r/page_reorganize.result
index 20e1600bd0d..fe85926e2b8 100644
--- a/mysql-test/suite/innodb/r/page_reorganize.result
+++ b/mysql-test/suite/innodb/r/page_reorganize.result
@@ -16,8 +16,6 @@ SET @save_dbug = @@debug_dbug;
 SET DEBUG_DBUG = '+d,do_page_reorganize,do_lock_reverse_page_reorganize';
 insert into t1(f2) values (repeat('+', 100));
 SET DEBUG = @save_dbug;
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 commit;
 connection con1;
 f1
diff --git a/mysql-test/suite/innodb_fts/r/ft_result_cache_limit.result b/mysql-test/suite/innodb_fts/r/ft_result_cache_limit.result
index 2dbdd5a04bc..74d60410d58 100644
--- a/mysql-test/suite/innodb_fts/r/ft_result_cache_limit.result
+++ b/mysql-test/suite/innodb_fts/r/ft_result_cache_limit.result
@@ -20,8 +20,6 @@ END//
 CALL populate_t1;
 SET autocommit=1;
 SET SESSION debug="+d,fts_instrument_result_cache_limit";
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 ALTER TABLE t1 ADD FULLTEXT INDEX `text_content_idx` (`text_content`);
 SELECT FTS_DOC_ID, text_content
 FROM t1
diff --git a/mysql-test/suite/innodb_gis/r/check_rtree.result b/mysql-test/suite/innodb_gis/r/check_rtree.result
index fe60a628fde..0d7b25b6b72 100644
--- a/mysql-test/suite/innodb_gis/r/check_rtree.result
+++ b/mysql-test/suite/innodb_gis/r/check_rtree.result
@@ -1,7 +1,5 @@
 create table t1 (i int, g geometry not null, spatial index (g))engine=innodb;
 SET SESSION debug="+d,rtree_test_check_count";
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 insert into t1 values (1, POINT(1,1));
 insert into t1 values (1, POINT(1.5,1.5));
 insert into t1 values (1, POINT(3,3));
diff --git a/mysql-test/suite/innodb_gis/r/rollback.result b/mysql-test/suite/innodb_gis/r/rollback.result
index 0d2b9c7cf2c..1efe5d284f7 100644
--- a/mysql-test/suite/innodb_gis/r/rollback.result
+++ b/mysql-test/suite/innodb_gis/r/rollback.result
@@ -408,8 +408,6 @@ update t1 set a=point(5,5), b=point(5,5), c=5 where i < 3;
 ERROR 23000: Duplicate entry '5' for key 'c'
 rollback;
 set session debug="+d,row_mysql_crash_if_error";
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 update t1 set a=point(5,5), b=point(5,5), c=5 where i < 3;
 ERROR HY000: Lost connection to server during query
 insert into t1 values(5, point(5,5), point(5,5), 5);
diff --git a/mysql-test/suite/innodb_gis/r/rtree_compress.result b/mysql-test/suite/innodb_gis/r/rtree_compress.result
index db9d5bd634c..9b646985dd4 100644
--- a/mysql-test/suite/innodb_gis/r/rtree_compress.result
+++ b/mysql-test/suite/innodb_gis/r/rtree_compress.result
@@ -44,8 +44,6 @@ count(*)
 0
 SET @saved_dbug = @@SESSION.debug_dbug;
 SET DEBUG='+d,page_copy_rec_list_start_compress_fail';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 delete from t1;
 select count(*) from t1 where MBRWithin(t1.c2, @g1);
 count(*)
diff --git a/mysql-test/suite/innodb_gis/r/rtree_create_inplace.result b/mysql-test/suite/innodb_gis/r/rtree_create_inplace.result
index a8898f5c98f..5279eea8aa8 100644
--- a/mysql-test/suite/innodb_gis/r/rtree_create_inplace.result
+++ b/mysql-test/suite/innodb_gis/r/rtree_create_inplace.result
@@ -31,7 +31,5 @@ COUNT(*)
 0
 ALTER TABLE t1 DROP INDEX idx, ADD SPATIAL INDEX idx3(c2);
 SET SESSION debug="+d,row_merge_instrument_log_check_flush";
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 ALTER TABLE t1  DROP INDEX idx3, ADD SPATIAL INDEX idx4(c2), ADD SPATIAL INDEX idx5(c3);
 DROP TABLE t1;
diff --git a/mysql-test/suite/rpl/r/rpl_semisync_ali_issues.result b/mysql-test/suite/rpl/r/rpl_semisync_ali_issues.result
index 36a2bac5838..530bbac633b 100644
--- a/mysql-test/suite/rpl/r/rpl_semisync_ali_issues.result
+++ b/mysql-test/suite/rpl/r/rpl_semisync_ali_issues.result
@@ -270,16 +270,12 @@ Variable_name	Value
 Rpl_semi_sync_master_clients	1
 # Test failure of select error .
 SET GLOBAL debug = 'd,rpl_semisync_simulate_select_error';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 INSERT INTO t1 VALUES(3);
 connection slave;
 connection con1;
 # Test failure of pthread_create
 SET GLOBAL rpl_semi_sync_master_enabled = 0;
 SET GLOBAL debug = 'd,rpl_semisync_simulate_create_thread_failure';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 SET GLOBAL rpl_semi_sync_master_enabled= ON;
 # Test failure of pthread_join
 SET GLOBAL rpl_semi_sync_master_enabled= OFF;
@@ -287,8 +283,6 @@ SET GLOBAL rpl_semi_sync_master_enabled= OFF;
 # Failure on registering semisync slave
 #
 SET GLOBAL debug= 'd,rpl_semisync_simulate_add_slave_failure';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 SET GLOBAL rpl_semi_sync_master_enabled= ON;
 connection slave;
 STOP SLAVE IO_THREAD;
@@ -297,8 +291,6 @@ START SLAVE IO_THREAD;
 include/wait_for_slave_io_to_start.inc
 connection con1;
 SET GLOBAL debug='';
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 connection slave;
 START SLAVE IO_THREAD;
 include/wait_for_slave_io_to_start.inc
diff --git a/mysql-test/suite/sys_vars/r/debug_basic.result b/mysql-test/suite/sys_vars/r/debug_basic.result
index a97ad65b40f..5a77446d036 100644
--- a/mysql-test/suite/sys_vars/r/debug_basic.result
+++ b/mysql-test/suite/sys_vars/r/debug_basic.result
@@ -1,6 +1,4 @@
 set session debug="L";
-Warnings:
-Warning	1287	'@@debug' is deprecated and will be removed in a future release. Please use '@@debug_dbug' instead
 select @@global.debug="1";
 @@global.debug="1"
 0
diff --git a/mysql-test/suite/sys_vars/r/sysvars_debug.result b/mysql-test/suite/sys_vars/r/sysvars_debug.result
index fc04ac83210..01f74170b1d 100644
--- a/mysql-test/suite/sys_vars/r/sysvars_debug.result
+++ b/mysql-test/suite/sys_vars/r/sysvars_debug.result
@@ -38,7 +38,7 @@ GLOBAL_VALUE_ORIGIN	COMPILE-TIME
 DEFAULT_VALUE	
 VARIABLE_SCOPE	SESSION
 VARIABLE_TYPE	VARCHAR
-VARIABLE_COMMENT	Built-in DBUG debugger
+VARIABLE_COMMENT	Built-in DBUG debugger. Alias for --debug
 NUMERIC_MIN_VALUE	NULL
 NUMERIC_MAX_VALUE	NULL
 NUMERIC_BLOCK_SIZE	NULL
diff --git a/scripts/mysql_setpermission.sh b/scripts/mysql_setpermission.sh
index b3c9c27ca88..aa165a5e742 100644
--- a/scripts/mysql_setpermission.sh
+++ b/scripts/mysql_setpermission.sh
@@ -68,7 +68,7 @@ usage() if ($opt_help); # the help function
 
 if ($opt_host =~ s/:(\d+)$//)
 {
-    $opt_port = $1;
+  $opt_port = $1;
 }
 
 if ($opt_host eq '')
@@ -98,7 +98,7 @@ my $prefix= 'mysql';
 if (eval {DBI->install_driver("MariaDB")}) {
   $dsn ="DBI:MariaDB:;";
   $prefix= 'mariadb';
-} 
+}
 else {
   $dsn = "DBI:mysql:;";
 }
@@ -226,11 +226,11 @@ sub setpwd
   {
     $pass = "PASSWORD(". $dbh->quote($pass) . ")";
   }
-  my $uh= "$user@$host";
+  my $uh= $user."@".$host;
   my $sth = $dbh->prepare("set password for $uh =$pass") || die $dbh->errstr;
   $sth->execute || die $dbh->errstr;
   $sth->finish;
-  print "The password is set for user $user.\n\n";
+  print "The password is set for user $uh.\n\n";
 
 }
 
diff --git a/sql/sys_vars.cc b/sql/sys_vars.cc
index 7550084456b..6e84d51a578 100644
--- a/sql/sys_vars.cc
+++ b/sql/sys_vars.cc
@@ -1003,11 +1003,10 @@ static Sys_var_charptr_fscs Sys_datadir(
 static Sys_var_dbug Sys_dbug(
        "debug", "Built-in DBUG debugger", sys_var::SESSION,
        CMD_LINE(OPT_ARG, '#'), DEFAULT(""), NO_MUTEX_GUARD, NOT_IN_BINLOG,
-       ON_CHECK(check_has_super), ON_UPDATE(0),
-       DEPRECATED("'@@debug_dbug'")); // since 5.5.37
+       ON_CHECK(check_has_super));
 
 static Sys_var_dbug Sys_debug_dbug(
-       "debug_dbug", "Built-in DBUG debugger", sys_var::SESSION,
+       "debug_dbug", "Built-in DBUG debugger. Alias for --debug", sys_var::SESSION,
        CMD_LINE(OPT_ARG, '#'), DEFAULT(""), NO_MUTEX_GUARD, NOT_IN_BINLOG,
        ON_CHECK(check_has_super));
 #endif
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index b38b1218fb6..17e512bf34e 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -15720,15 +15720,17 @@ ha_innobase::extra(
 {
 	/* Warning: since it is not sure that MariaDB calls external_lock()
 	before calling this function, m_prebuilt->trx can be obsolete! */
-	trx_t* trx = check_trx_exists(ha_thd());
+	trx_t* trx;
 
 	switch (operation) {
 	case HA_EXTRA_FLUSH:
+		(void)check_trx_exists(ha_thd());
 		if (m_prebuilt->blob_heap) {
 			row_mysql_prebuilt_free_blob_heap(m_prebuilt);
 		}
 		break;
 	case HA_EXTRA_RESET_STATE:
+		trx = check_trx_exists(ha_thd());
 		reset_template();
 		trx->duplicates = 0;
 	stmt_boundary:
@@ -15736,18 +15738,23 @@ ha_innobase::extra(
 		trx->bulk_insert = false;
 		break;
 	case HA_EXTRA_NO_KEYREAD:
+		(void)check_trx_exists(ha_thd());
 		m_prebuilt->read_just_key = 0;
 		break;
 	case HA_EXTRA_KEYREAD:
+		(void)check_trx_exists(ha_thd());
 		m_prebuilt->read_just_key = 1;
 		break;
 	case HA_EXTRA_KEYREAD_PRESERVE_FIELDS:
+		(void)check_trx_exists(ha_thd());
 		m_prebuilt->keep_other_fields_on_keyread = 1;
 		break;
 	case HA_EXTRA_INSERT_WITH_UPDATE:
+		trx = check_trx_exists(ha_thd());
 		trx->duplicates |= TRX_DUP_IGNORE;
 		goto stmt_boundary;
 	case HA_EXTRA_NO_IGNORE_DUP_KEY:
+		trx = check_trx_exists(ha_thd());
 		trx->duplicates &= ~TRX_DUP_IGNORE;
 		if (trx->is_bulk_insert()) {
 			/* Allow a subsequent INSERT into an empty table
@@ -15756,9 +15763,11 @@ ha_innobase::extra(
 		}
 		goto stmt_boundary;
 	case HA_EXTRA_WRITE_CAN_REPLACE:
+		trx = check_trx_exists(ha_thd());
 		trx->duplicates |= TRX_DUP_REPLACE;
 		goto stmt_boundary;
 	case HA_EXTRA_WRITE_CANNOT_REPLACE:
+		trx = check_trx_exists(ha_thd());
 		trx->duplicates &= ~TRX_DUP_REPLACE;
 		if (trx->is_bulk_insert()) {
 			/* Allow a subsequent INSERT into an empty table
@@ -15767,6 +15776,7 @@ ha_innobase::extra(
 		}
 		goto stmt_boundary;
 	case HA_EXTRA_BEGIN_ALTER_COPY:
+		trx = check_trx_exists(ha_thd());
 		m_prebuilt->table->skip_alter_undo = 1;
 		if (m_prebuilt->table->is_temporary()
 		    || !m_prebuilt->table->versioned_by_id()) {
@@ -15779,6 +15789,7 @@ ha_innobase::extra(
 			.first->second.set_versioned(0);
 		break;
 	case HA_EXTRA_END_ALTER_COPY:
+		trx = check_trx_exists(ha_thd());
 		m_prebuilt->table->skip_alter_undo = 0;
 		if (!m_prebuilt->table->is_temporary()
 		    && !high_level_read_only) {
diff --git a/storage/innobase/mtr/mtr0mtr.cc b/storage/innobase/mtr/mtr0mtr.cc
index 7ce54a9b04d..ccbd88c5231 100644
--- a/storage/innobase/mtr/mtr0mtr.cc
+++ b/storage/innobase/mtr/mtr0mtr.cc
@@ -160,10 +160,16 @@ void mtr_t::commit()
     {
       ut_ad(m_log_mode == MTR_LOG_NO_REDO);
       ut_ad(m_log.size() == 0);
-      m_commit_lsn= log_sys.get_lsn();
-      lsns= { m_commit_lsn, PAGE_FLUSH_NO };
       if (UNIV_UNLIKELY(m_made_dirty)) /* This should be IMPORT TABLESPACE */
+      {
+        mysql_mutex_lock(&log_sys.mutex);
+        m_commit_lsn= log_sys.get_lsn();
         mysql_mutex_lock(&log_sys.flush_order_mutex);
+        mysql_mutex_unlock(&log_sys.mutex);
+      }
+      else
+        m_commit_lsn= log_sys.get_lsn();
+      lsns= { m_commit_lsn, PAGE_FLUSH_NO };
     }
 
     if (m_freed_pages)