Merge 10.5 into 10.6

include/my_atomic_wrapper.h

@@ -13,6 +13,7 @@
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
 
+#pragma once
 #ifdef __cplusplus
 #include <atomic>
 /**

mysql-test/include/innodb_checksum_algorithm.combinations

@@ -3,9 +3,11 @@
 
 [strict_crc32]
 --innodb-checksum-algorithm=strict_crc32
+--innodb-flush-sync=OFF
 
 [full_crc32]
 --innodb-checksum-algorithm=full_crc32
 
 [strict_full_crc32]
 --innodb-checksum-algorithm=strict_full_crc32
+--innodb-flush-sync=OFF

mysql-test/main/range.result

@@ -1297,7 +1297,7 @@ SELECT * FROM t1 WHERE
 25 <= a AND b = 23 OR
 23 <= a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	range	a	a	5	NULL	2	Using where; Using index
+1	SIMPLE	t1	range	a	a	5	NULL	3	Using where; Using index
 SELECT * FROM t1 WHERE
 23 <= a AND a <= 25 OR
 25 <= a AND b = 23 OR
@@ -3121,6 +3121,39 @@ a	b
 set eq_range_index_dive_limit=default;
 drop table t1;
 #
+# MDEV-24117: Memory management problem in statistics state...
+#  (just the testcase)
+#
+create table t0(a int);
+insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+create table t1(a int);
+insert into t1
+select A.a + B.a* 10 + C.a * 100 + D.a * 1000
+from t0 A, t0 B, t0 C, t0 D
+where D.a<4;
+create table t2 (
+a int,
+b int,
+key(a)
+);
+insert into t2 values (1,1),(2,2),(3,3);
+set @query=(select group_concat(a) from t1);
+set @tmp_24117= @@max_session_mem_used;
+#
+# On debug build, the usage was
+#  - 2.8M without the bug
+#  - 1G with the bug.
+set max_session_mem_used=64*1024*1024;
+set @query=concat('explain select * from t2 where a=1 or a in (', @query, ')');
+prepare s from @query;
+# This should not fail with an error:
+execute s;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	a	NULL	NULL	NULL	3	Using where
+set max_session_mem_used=@tmp_24117;
+deallocate prepare s;
+drop table t0,t1,t2;
+#
 # MDEV-23811: Both disjunct of WHERE condition contain range conditions
 #             for the same index such that the second range condition
 #             fully covers the first one. Additionally one of the disjuncts

mysql-test/main/range.test

@@ -2092,6 +2092,52 @@ set eq_range_index_dive_limit=default;
 
 drop table t1;
 
+--echo #
+--echo # MDEV-24117: Memory management problem in statistics state...
+--echo #  (just the testcase)
+--echo #
+
+create table t0(a int);
+insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+
+create table t1(a int);
+
+# 4K rows
+insert into t1
+select A.a + B.a* 10 + C.a * 100 + D.a * 1000
+from t0 A, t0 B, t0 C, t0 D
+where D.a<4;
+
+create table t2 (
+  a int,
+  b int,
+  key(a)
+);
+
+insert into t2 values (1,1),(2,2),(3,3);
+
+set @query=(select group_concat(a) from t1);
+
+set @tmp_24117= @@max_session_mem_used;
+
+--echo #
+--echo # On debug build, the usage was
+--echo #  - 2.8M without the bug
+--echo #  - 1G with the bug.
+
+set max_session_mem_used=64*1024*1024;
+
+set @query=concat('explain select * from t2 where a=1 or a in (', @query, ')');
+
+prepare s from @query;
+
+--echo # This should not fail with an error:
+execute s;
+set max_session_mem_used=@tmp_24117;
+
+deallocate prepare s;
+
+drop table t0,t1,t2;
 --echo #
 --echo # MDEV-23811: Both disjunct of WHERE condition contain range conditions
 --echo #             for the same index such that the second range condition

mysql-test/main/range_mrr_icp.result

@@ -1300,7 +1300,7 @@ SELECT * FROM t1 WHERE
 25 <= a AND b = 23 OR
 23 <= a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	range	a	a	5	NULL	2	Using where; Using index
+1	SIMPLE	t1	range	a	a	5	NULL	3	Using where; Using index
 SELECT * FROM t1 WHERE
 23 <= a AND a <= 25 OR
 25 <= a AND b = 23 OR
@@ -3110,6 +3110,39 @@ a	b
 set eq_range_index_dive_limit=default;
 drop table t1;
 #
+# MDEV-24117: Memory management problem in statistics state...
+#  (just the testcase)
+#
+create table t0(a int);
+insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+create table t1(a int);
+insert into t1
+select A.a + B.a* 10 + C.a * 100 + D.a * 1000
+from t0 A, t0 B, t0 C, t0 D
+where D.a<4;
+create table t2 (
+a int,
+b int,
+key(a)
+);
+insert into t2 values (1,1),(2,2),(3,3);
+set @query=(select group_concat(a) from t1);
+set @tmp_24117= @@max_session_mem_used;
+#
+# On debug build, the usage was
+#  - 2.8M without the bug
+#  - 1G with the bug.
+set max_session_mem_used=64*1024*1024;
+set @query=concat('explain select * from t2 where a=1 or a in (', @query, ')');
+prepare s from @query;
+# This should not fail with an error:
+execute s;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	a	NULL	NULL	NULL	3	Using where
+set max_session_mem_used=@tmp_24117;
+deallocate prepare s;
+drop table t0,t1,t2;
+#
 # MDEV-23811: Both disjunct of WHERE condition contain range conditions
 #             for the same index such that the second range condition
 #             fully covers the first one. Additionally one of the disjuncts

mysql-test/suite/maria/create.test

@@ -86,11 +86,6 @@ flush tables;
 --error 1,ER_TABLE_EXISTS_ERROR
 --eval CREATE TABLE MDEV_23222 (i INT) DATA DIRECTORY = '$MYSQL_TMP_DIR', ENGINE=Aria TRANSACTIONAL=1;
 DROP TABLE t1;
---disable_warnings
---remove_file $mysqld_datadir/test/MDEV_23222.MAD
---replace_result $MYSQL_TMP_DIR MYSQL_TMP_DIR
---remove_file $MYSQL_TMP_DIR/MDEV_23222.MAD
---enable_warnings
 
 --echo #
 --echo # End of 10.3 tests

mysql-test/suite/sys_vars/r/innodb_flush_sync_basic.result

@@ -1,16 +1,11 @@
 SET @start_global_value = @@global.innodb_flush_sync;
-SELECT @start_global_value;
-@start_global_value
-1
 Valid values are 'ON' and 'OFF'
 select @@global.innodb_flush_sync in (0, 1);
 @@global.innodb_flush_sync in (0, 1)
 1
-select @@global.innodb_flush_sync;
-@@global.innodb_flush_sync
-1
 select @@session.innodb_flush_sync;
 ERROR HY000: Variable 'innodb_flush_sync' is a GLOBAL variable
+SET GLOBAL innodb_flush_sync = ON;
 show global variables like 'innodb_flush_sync';
 Variable_name	Value
 innodb_flush_sync	ON
@@ -87,6 +82,3 @@ INNODB_FLUSH_SYNC	ON
 set global innodb_flush_sync='AUTO';
 ERROR 42000: Variable 'innodb_flush_sync' can't be set to the value of 'AUTO'
 SET @@global.innodb_flush_sync = @start_global_value;
-SELECT @@global.innodb_flush_sync;
-@@global.innodb_flush_sync
-1

mysql-test/suite/sys_vars/t/innodb_flush_sync_basic.test

@@ -1,16 +1,15 @@
 --source include/have_innodb.inc
 
 SET @start_global_value = @@global.innodb_flush_sync;
-SELECT @start_global_value;
 
 #
 # exists as global only
 #
 --echo Valid values are 'ON' and 'OFF'
 select @@global.innodb_flush_sync in (0, 1);
-select @@global.innodb_flush_sync;
 --error ER_INCORRECT_GLOBAL_LOCAL_VAR
 select @@session.innodb_flush_sync;
+SET GLOBAL innodb_flush_sync = ON;
 show global variables like 'innodb_flush_sync';
 show session variables like 'innodb_flush_sync';
 --disable_warnings
@@ -18,9 +17,6 @@ select * from information_schema.global_variables where variable_name='innodb_fl
 select * from information_schema.session_variables where variable_name='innodb_flush_sync';
 --enable_warnings
 
-#
-# show that it's writable
-#
 set global innodb_flush_sync='OFF';
 select @@global.innodb_flush_sync;
 --disable_warnings
@@ -74,4 +70,3 @@ set global innodb_flush_sync='AUTO';
 #
 
 SET @@global.innodb_flush_sync = @start_global_value;
-SELECT @@global.innodb_flush_sync;

sql/opt_range.cc

@@ -9619,15 +9619,9 @@ tree_or(RANGE_OPT_PARAM *param,SEL_TREE *tree1,SEL_TREE *tree2)
   }
   bool no_imerge_from_ranges= FALSE;
 
-  SEL_TREE *rt1= tree1;
-  SEL_TREE *rt2= tree2;
   /* Build the range part of the tree for the formula (1) */ 
   if (sel_trees_can_be_ored(param, tree1, tree2, &ored_keys))
   {
-    if (no_merges1)
-      rt1= new SEL_TREE(tree1, TRUE, param);
-    if (no_merges2)
-      rt2= new SEL_TREE(tree2, TRUE, param);
     bool must_be_ored= sel_trees_must_be_ored(param, tree1, tree2, ored_keys);
     no_imerge_from_ranges= must_be_ored;
 
@@ -9685,6 +9679,12 @@ tree_or(RANGE_OPT_PARAM *param,SEL_TREE *tree1,SEL_TREE *tree2)
   else if (!no_ranges1 && !no_ranges2 && !no_imerge_from_ranges)
   {
     /* Build the imerge part of the tree for the formula (1) */
+    SEL_TREE *rt1= tree1;
+    SEL_TREE *rt2= tree2;
+    if (no_merges1)
+      rt1= new SEL_TREE(tree1, TRUE, param);
+    if (no_merges2)
+      rt2= new SEL_TREE(tree2, TRUE, param);
     if (!rt1 || !rt2 ||
         result->merges.push_back(imerge_from_ranges) ||
         imerge_from_ranges->or_sel_tree(param, rt1) ||
@@ -10350,7 +10350,7 @@ key_or(RANGE_OPT_PARAM *param, SEL_ARG *key1,SEL_ARG *key2)
       if (!tmp->next_key_part)
       {
 	SEL_ARG *key2_next= key2->next;
-        if (key2->use_count)
+	if (key2_shared)
 	{
 	  SEL_ARG *key2_cpy= new SEL_ARG(*key2);
           if (!key2_cpy)

sql/sql_prepare.cc

@@ -3252,10 +3252,19 @@ void mysqld_stmt_execute(THD *thd, char *packet_arg, uint packet_length)
 void mysqld_stmt_bulk_execute(THD *thd, char *packet_arg, uint packet_length)
 {
   uchar *packet= (uchar*)packet_arg; // GCC 4.0.1 workaround
+  DBUG_ENTER("mysqld_stmt_execute_bulk");
+
+  const uint packet_header_lenght= 4 + 2; //ID & 2 bytes of flags
+
+  if (packet_length < packet_header_lenght)
+  {
+    my_error(ER_MALFORMED_PACKET, MYF(0));
+    DBUG_VOID_RETURN;
+  }
+
   ulong stmt_id= uint4korr(packet);
   uint flags= (uint) uint2korr(packet + 4);
   uchar *packet_end= packet + packet_length;
-  DBUG_ENTER("mysqld_stmt_execute_bulk");
 
   if (!(thd->client_capabilities &
         MARIADB_CLIENT_STMT_BULK_OPERATIONS))
@@ -3263,16 +3272,18 @@ void mysqld_stmt_bulk_execute(THD *thd, char *packet_arg, uint packet_length)
     DBUG_PRINT("error",
                ("An attempt to execute bulk operation without support"));
     my_error(ER_UNSUPPORTED_PS, MYF(0));
+    DBUG_VOID_RETURN;
   }
   /* Check for implemented parameters */
   if (flags & (~STMT_BULK_FLAG_CLIENT_SEND_TYPES))
   {
     DBUG_PRINT("error", ("unsupported bulk execute flags %x", flags));
     my_error(ER_UNSUPPORTED_PS, MYF(0));
+    DBUG_VOID_RETURN;
   }
 
   /* stmt id and two bytes of flags */
-  packet+= 4 + 2;
+  packet+= packet_header_lenght;
   mysql_stmt_execute_common(thd, stmt_id, packet, packet_end, 0, TRUE,
                             (flags & STMT_BULK_FLAG_CLIENT_SEND_TYPES));
   DBUG_VOID_RETURN;
@@ -3349,9 +3360,11 @@ stmt_execute_packet_sanity_check(Prepared_statement *stmt,
   {
     /*
       If there is no parameters, this should be normally already end
-      of the packet. If it's not - then error
+      of the packet, but it is not a problem if something left (popular
+      mistake in protocol implementation) because we will not read anymore
+      from the buffer.
     */
-    return (packet_end > packet);
+    return false;
   }
   return false;
 }

storage/innobase/buf/buf0flu.cc

@@ -1681,16 +1681,15 @@ ATTRIBUTE_COLD void buf_flush_wait_flushed(lsn_t sync_lsn)
 
   mysql_mutex_lock(&buf_pool.flush_list_mutex);
 
+  if (buf_pool.get_oldest_modification(sync_lsn) < sync_lsn)
+  {
 #if 1 /* FIXME: remove this, and guarantee that the page cleaner serves us */
     if (UNIV_UNLIKELY(!buf_page_cleaner_is_active)
         ut_d(|| innodb_page_cleaner_disabled_debug))
     {
-    for (;;)
+      do
       {
-      const lsn_t lsn= buf_pool.get_oldest_modification(sync_lsn);
         mysql_mutex_unlock(&buf_pool.flush_list_mutex);
-      if (lsn >= sync_lsn)
-        return;
         ulint n_pages= buf_flush_lists(srv_max_io_capacity, sync_lsn);
         buf_flush_wait_batch_end_acquiring_mutex(false);
         if (n_pages)
@@ -1698,24 +1697,22 @@ ATTRIBUTE_COLD void buf_flush_wait_flushed(lsn_t sync_lsn)
           MONITOR_INC_VALUE_CUMULATIVE(MONITOR_FLUSH_SYNC_TOTAL_PAGE,
                                        MONITOR_FLUSH_SYNC_COUNT,
                                        MONITOR_FLUSH_SYNC_PAGES, n_pages);
-        log_checkpoint();
         }
         MONITOR_INC(MONITOR_FLUSH_SYNC_WAITS);
         mysql_mutex_lock(&buf_pool.flush_list_mutex);
       }
-    return;
+      while (buf_pool.get_oldest_modification(sync_lsn) < sync_lsn);
+
+      goto try_checkpoint;
     }
-  else if (UNIV_LIKELY(srv_flush_sync))
 #endif
-  {
     if (buf_flush_sync_lsn < sync_lsn)
     {
       buf_flush_sync_lsn= sync_lsn;
       mysql_cond_signal(&buf_pool.do_flush_list);
     }
-  }
 
-  while (buf_pool.get_oldest_modification(sync_lsn) < sync_lsn)
+    do
     {
       tpool::tpool_wait_begin();
       thd_wait_begin(nullptr, THD_WAIT_DISKIO);
@@ -1725,8 +1722,14 @@ ATTRIBUTE_COLD void buf_flush_wait_flushed(lsn_t sync_lsn)
 
       MONITOR_INC(MONITOR_FLUSH_SYNC_WAITS);
     }
+    while (buf_pool.get_oldest_modification(sync_lsn) < sync_lsn);
+  }
 
+try_checkpoint:
   mysql_mutex_unlock(&buf_pool.flush_list_mutex);
+
+  if (UNIV_UNLIKELY(log_sys.last_checkpoint_lsn < sync_lsn))
+    log_checkpoint();
 }
 
 /** If innodb_flush_sync=ON, initiate a furious flush.
@@ -1739,8 +1742,7 @@ void buf_flush_ahead(lsn_t lsn)
   if (recv_recovery_is_on())
     recv_sys.apply(true);
 
-  if (buf_flush_sync_lsn < lsn &&
+  if (buf_flush_sync_lsn < lsn)
-      UNIV_LIKELY(srv_flush_sync) && UNIV_LIKELY(buf_page_cleaner_is_active))
   {
     mysql_mutex_lock(&buf_pool.flush_list_mutex);
     if (buf_flush_sync_lsn < lsn)
@@ -2054,13 +2056,15 @@ static os_thread_ret_t DECLARE_THREAD(buf_flush_page_cleaner)(void*)
     if (UNIV_UNLIKELY(lsn_limit != 0))
     {
 furious_flush:
+      if (UNIV_LIKELY(srv_flush_sync))
+      {
         buf_flush_sync_for_checkpoint(lsn_limit);
         last_pages= 0;
         set_timespec(abstime, 1);
         continue;
       }
-
+    }
-    if (srv_shutdown_state > SRV_SHUTDOWN_INITIATED)
+    else if (srv_shutdown_state > SRV_SHUTDOWN_INITIATED)
       break;
 
     mysql_cond_timedwait(&buf_pool.do_flush_list, &buf_pool.flush_list_mutex,
@@ -2070,15 +2074,25 @@ furious_flush:
     lsn_limit= buf_flush_sync_lsn;
 
     if (UNIV_UNLIKELY(lsn_limit != 0))
+    {
+      if (UNIV_LIKELY(srv_flush_sync))
         goto furious_flush;
-
+    }
-    if (srv_shutdown_state > SRV_SHUTDOWN_INITIATED)
+    else if (srv_shutdown_state > SRV_SHUTDOWN_INITIATED)
       break;
 
     const ulint dirty_blocks= UT_LIST_GET_LEN(buf_pool.flush_list);
 
     if (!dirty_blocks)
+    {
+      if (UNIV_UNLIKELY(lsn_limit != 0))
+      {
+        buf_flush_sync_lsn= 0;
+        /* wake up buf_flush_wait_flushed() */
+        mysql_cond_broadcast(&buf_pool.done_flush_list);
+      }
       continue;
+    }
 
     /* We perform dirty reads of the LRU+free list lengths here.
     Division by zero is not possible, because buf_pool.flush_list is
@@ -2086,19 +2100,29 @@ furious_flush:
     const double dirty_pct= double(dirty_blocks) * 100.0 /
       double(UT_LIST_GET_LEN(buf_pool.LRU) + UT_LIST_GET_LEN(buf_pool.free));
 
-    if (dirty_pct < srv_max_dirty_pages_pct_lwm)
+    if (dirty_pct < srv_max_dirty_pages_pct_lwm && !lsn_limit)
       continue;
 
     const lsn_t oldest_lsn= buf_pool.get_oldest_modification(0);
 
+    if (UNIV_UNLIKELY(lsn_limit != 0) && oldest_lsn >= lsn_limit)
+      buf_flush_sync_lsn= 0;
+
     mysql_mutex_unlock(&buf_pool.flush_list_mutex);
 
     ulint n_flushed;
 
-    if (!srv_adaptive_flushing)
+    if (UNIV_UNLIKELY(lsn_limit != 0))
+    {
+      n_flushed= buf_flush_lists(srv_max_io_capacity, lsn_limit);
+      /* wake up buf_flush_wait_flushed() */
+      mysql_cond_broadcast(&buf_pool.done_flush_list);
+      goto try_checkpoint;
+    }
+    else if (!srv_adaptive_flushing)
     {
       n_flushed= buf_flush_lists(srv_io_capacity, LSN_MAX);
-
+try_checkpoint:
       if (n_flushed)
       {
         MONITOR_INC_VALUE_CUMULATIVE(MONITOR_FLUSH_BACKGROUND_TOTAL_PAGE,

storage/innobase/handler/ha_innodb.cc

@@ -18322,24 +18322,6 @@ static struct st_mysql_storage_engine innobase_storage_engine=
 { MYSQL_HANDLERTON_INTERFACE_VERSION };
 
 #ifdef WITH_WSREP
-void
-wsrep_abort_slave_trx(
-/*==================*/
-	wsrep_seqno_t bf_seqno,
-	wsrep_seqno_t victim_seqno)
-{
-	WSREP_ERROR("Trx %lld tries to abort slave trx %lld. This could be "
-		"caused by:\n\t"
-		"1) unsupported configuration options combination, please check documentation.\n\t"
-		"2) a bug in the code.\n\t"
-		"3) a database corruption.\n Node consistency compromized, "
-		"need to abort. Restart the node to resync with cluster.",
-		(long long)bf_seqno, (long long)victim_seqno);
-	abort();
-}
-
-/*******************************************************************//**
-This function is used to kill one transaction in BF. */
 
 /** This function is used to kill one transaction.
 
@@ -18364,10 +18346,7 @@ comparison as in the local certification failure.
 @param[in]	bf_thd		Brute force (BF) thread
 @param[in,out]	victim_trx	Vimtim trx to be killed
 @param[in]	signal		Should victim be signaled */
-UNIV_INTERN
+int wsrep_innobase_kill_one_trx(THD *bf_thd, trx_t *victim_trx, bool signal)
-int
-wsrep_innobase_kill_one_trx(THD* bf_thd, trx_t *victim_trx,
-			    bool signal)
 {
 	ut_ad(bf_thd);
 	ut_ad(victim_trx);
@@ -18376,7 +18355,7 @@ wsrep_innobase_kill_one_trx(THD* bf_thd, trx_t *victim_trx,
 
 	DBUG_ENTER("wsrep_innobase_kill_one_trx");
 
-	THD *thd= (THD *) victim_trx->mysql_thd;
+	THD *thd= victim_trx->mysql_thd;
 	ut_ad(thd);
 	/* Note that bf_trx might not exist here e.g. on MDL conflict
 	case (test: galera_concurrent_ctas). Similarly, BF thread

storage/innobase/handler/i_s.cc

@@ -6786,6 +6786,7 @@ i_s_tablespaces_encryption_fill_table(
 		DBUG_RETURN(0);
 	}
 
+	int err = 0;
 	mutex_enter(&fil_system.mutex);
 	fil_system.freeze_space_list++;
 
@@ -6795,19 +6796,19 @@ i_s_tablespaces_encryption_fill_table(
 		    && !space->is_stopping()) {
 			space->reacquire();
 			mutex_exit(&fil_system.mutex);
-			if (int err = i_s_dict_fill_tablespaces_encryption(
+			err = i_s_dict_fill_tablespaces_encryption(
-				    thd, space, tables->table)) {
+				thd, space, tables->table);
-				space->release();
-				DBUG_RETURN(err);
-			}
 			mutex_enter(&fil_system.mutex);
 			space->release();
+			if (err) {
+				break;
+			}
 		}
 	}
 
 	fil_system.freeze_space_list--;
 	mutex_exit(&fil_system.mutex);
-	DBUG_RETURN(0);
+	DBUG_RETURN(err);
 }
 /*******************************************************************//**
 Bind the dynamic table INFORMATION_SCHEMA.INNODB_TABLESPACES_ENCRYPTION

storage/innobase/include/ha_prototypes.h

@@ -217,9 +217,7 @@ innobase_casedn_str(
 	char*	a);	/*!< in/out: string to put in lower case */
 
 #ifdef WITH_WSREP
-int
+int wsrep_innobase_kill_one_trx(THD *bf_thd, trx_t *victim_trx, bool signal);
-wsrep_innobase_kill_one_trx(THD *bf_thd, trx_t *victim_trx,
-			    bool signal);
 ulint wsrep_innobase_mysql_sort(int mysql_type, uint charset_number,
                              unsigned char* str, ulint str_length,
                              unsigned int buf_length);

storage/innobase/include/log0log.h

@@ -37,7 +37,7 @@ Created 12/9/1995 Heikki Tuuri
 #include "log0types.h"
 #include "os0file.h"
 #include "span.h"
-#include <atomic>
+#include "my_atomic_wrapper.h"
 #include <vector>
 #include <string>
 
@@ -615,8 +615,8 @@ public:
 					new query step is started */
 	ib_uint64_t	next_checkpoint_no;
 					/*!< next checkpoint number */
-	lsn_t		last_checkpoint_lsn;
+  /** latest completed checkpoint (protected by log_sys.mutex) */
-					/*!< latest checkpoint lsn */
+  Atomic_relaxed<lsn_t> last_checkpoint_lsn;
 	lsn_t		next_checkpoint_lsn;
 					/*!< next checkpoint lsn */
 	ulint		n_pending_checkpoint_writes;

storage/innobase/lock/lock0lock.cc

@@ -4753,7 +4753,7 @@ lock_validate()
 
 	lock_mutex_exit();
 
-	for (const page_id_t page_id : pages) {
+	for (page_id_t page_id : pages) {
 		lock_rec_block_validate(page_id);
 	}
 

storage/innobase/log/log0log.cc

@@ -918,7 +918,7 @@ ATTRIBUTE_COLD void log_write_checkpoint_info(lsn_t end_lsn)
 
 	DBUG_PRINT("ib_log", ("checkpoint ended at " LSN_PF
 			      ", flushed to " LSN_PF,
-			      log_sys.last_checkpoint_lsn,
+			      lsn_t{log_sys.last_checkpoint_lsn},
 			      log_sys.get_flushed_lsn()));
 
 	MONITOR_INC(MONITOR_NUM_CHECKPOINT);
@@ -1233,7 +1233,7 @@ log_print(
 		lsn,
 		log_sys.get_flushed_lsn(),
 		pages_flushed,
-		log_sys.last_checkpoint_lsn);
+		lsn_t{log_sys.last_checkpoint_lsn});
 
 	current_time = time(NULL);
 

storage/innobase/log/log0recv.cc

@@ -96,13 +96,22 @@ struct log_phys_t : public log_rec_t
   /** start LSN of the mini-transaction (not necessarily of this record) */
   const lsn_t start_lsn;
 private:
-  /** length  of the record, in bytes */
+  /** @return the start of length and data */
-  uint16_t len;
+  const byte *start() const
+  {
+    return my_assume_aligned<sizeof(size_t)>
+      (reinterpret_cast<const byte*>(&start_lsn + 1));
+  }
+  /** @return the start of length and data */
+  byte *start()
+  { return const_cast<byte*>(const_cast<const log_phys_t*>(this)->start()); }
+  /** @return the length of the following record */
+  uint16_t len() const { uint16_t i; memcpy(&i, start(), 2); return i; }
 
   /** @return start of the log records */
-  byte *begin() { return reinterpret_cast<byte*>(&len + 1); }
+  byte *begin() { return start() + 2; }
   /** @return end of the log records */
-  byte *end() { byte *e= begin() + len; ut_ad(!*e); return e; }
+  byte *end() { byte *e= begin() + len(); ut_ad(!*e); return e; }
 public:
   /** @return start of the log records */
   const byte *begin() const { return const_cast<log_phys_t*>(this)->begin(); }
@@ -112,11 +121,7 @@ public:
   /** Determine the allocated size of the object.
   @param len  length of recs, excluding terminating NUL byte
   @return the total allocation size */
-  static size_t alloc_size(size_t len)
+  static inline size_t alloc_size(size_t len);
-  {
-    return len + 1 +
-      reinterpret_cast<size_t>(reinterpret_cast<log_phys_t*>(0)->begin());
-  }
 
   /** Constructor.
   @param start_lsn start LSN of the mini-transaction
@@ -124,11 +129,13 @@ public:
   @param recs the first log record for the page in the mini-transaction
   @param size length of recs, in bytes, excluding terminating NUL byte */
   log_phys_t(lsn_t start_lsn, lsn_t lsn, const byte *recs, size_t size) :
-    log_rec_t(lsn), start_lsn(start_lsn), len(static_cast<uint16_t>(size))
+    log_rec_t(lsn), start_lsn(start_lsn)
   {
     ut_ad(start_lsn);
     ut_ad(start_lsn < lsn);
+    const uint16_t len= static_cast<uint16_t>(size);
     ut_ad(len == size);
+    memcpy(start(), &len, 2);
     reinterpret_cast<byte*>(memcpy(begin(), recs, size))[size]= 0;
   }
 
@@ -138,8 +145,10 @@ public:
   void append(const byte *recs, size_t size)
   {
     ut_ad(start_lsn < lsn);
+    uint16_t l= len();
     reinterpret_cast<byte*>(memcpy(end(), recs, size))[size]= 0;
-    len= static_cast<uint16_t>(len + size);
+    l= static_cast<uint16_t>(l + size);
+    memcpy(start(), &l, 2);
   }
 
   /** Apply an UNDO_APPEND record.
@@ -514,6 +523,12 @@ page_corrupted:
 };
 
 
+inline size_t log_phys_t::alloc_size(size_t len)
+{
+  return len + (1 + 2 + sizeof(log_phys_t));
+}
+
+
 /** Tablespace item during recovery */
 struct file_name_t {
 	/** Tablespace file name (FILE_MODIFY) */

storage/innobase/trx/trx0rec.cc

@@ -53,15 +53,18 @@ const dtuple_t trx_undo_metadata = {
 /*=========== UNDO LOG RECORD CREATION AND DECODING ====================*/
 
 /** Calculate the free space left for extending an undo log record.
-@param[in]	undo_block	undo log page
+@param undo_block    undo log page
-@param[in]	ptr		current end of the undo page
+@param ptr           current end of the undo page
 @return bytes left */
 static ulint trx_undo_left(const buf_block_t *undo_block, const byte *ptr)
 {
-	/* The 10 is a safety margin, in case we have some small
+  ut_ad(ptr >= &undo_block->frame[TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_HDR_SIZE]);
-	calculation error below */
+  ut_ad(ptr <= &undo_block->frame[srv_page_size - 10 - FIL_PAGE_DATA_END]);
-	return srv_page_size - ulint(ptr - undo_block->frame)
+
-		- (10 + FIL_PAGE_DATA_END);
+  /* The 10 is supposed to be an extra safety margin (and needed for
+  compatibility with older versions) */
+  return srv_page_size - ulint(ptr - undo_block->frame) -
+    (10 + FIL_PAGE_DATA_END);
 }
 
 /**********************************************************************//**
@@ -133,17 +136,15 @@ trx_undo_log_v_idx(
 
 	ut_ad(!vcol->v_indexes.empty());
 
-	/* Size to reserve, max 5 bytes for each index id and position, plus
+	ulint		size = first_v_col ? 1 + 2 : 2;
-	5 bytes for num of indexes, 2 bytes for write total length.
-	1 byte for undo log record format version marker */
-	ulint		size = 5 + 2 + (first_v_col ? 1 : 0);
 	const ulint	avail = trx_undo_left(undo_block, ptr);
 
-	if (avail < size) {
+	/* The mach_write_compressed(ptr, flen) in
+	trx_undo_page_report_modify() will consume additional 1 to 5 bytes. */
+	if (avail < size + 5) {
 		return(NULL);
 	}
 
-	size = 0;
 	ulint n_idx = 0;
 	for (const auto& v_index : vcol->v_indexes) {
 		n_idx++;
@@ -151,12 +152,14 @@ trx_undo_log_v_idx(
 		size += mach_get_compressed_size(uint32_t(v_index.index->id));
 		size += mach_get_compressed_size(v_index.nth_field);
 	}
-	size += 2 + mach_get_compressed_size(n_idx);
 
-	if (avail < size) {
+	size += mach_get_compressed_size(n_idx);
+
+	if (avail < size + 5) {
 		return(NULL);
 	}
 
+	ut_d(const byte* orig_ptr = ptr);
 
 	if (first_v_col) {
 		/* write the version marker */
@@ -179,6 +182,8 @@ trx_undo_log_v_idx(
 		ptr += mach_write_compressed(ptr, v_index.nth_field);
 	}
 
+	ut_ad(orig_ptr + size == ptr);
+
 	mach_write_to_2(old_ptr, ulint(ptr - old_ptr));
 
 	return(ptr);
@@ -394,9 +399,6 @@ trx_undo_page_report_insert(
 						+ undo_block->frame));
 	byte* ptr = undo_block->frame + first_free;
 
-	ut_ad(first_free >= TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_HDR_SIZE);
-	ut_ad(first_free <= srv_page_size - FIL_PAGE_DATA_END);
-
 	if (trx_undo_left(undo_block, ptr) < 2 + 1 + 11 + 11) {
 		/* Not enough space for writing the general parameters */
 		return(0);
@@ -803,9 +805,6 @@ trx_undo_page_report_modify(
 	const uint16_t first_free = mach_read_from_2(ptr_to_first_free);
 	byte *ptr = undo_block->frame + first_free;
 
-	ut_ad(first_free >= TRX_UNDO_PAGE_HDR + TRX_UNDO_PAGE_HDR_SIZE);
-	ut_ad(first_free <= srv_page_size - FIL_PAGE_DATA_END);
-
 	if (trx_undo_left(undo_block, ptr) < 50) {
 		/* NOTE: the value 50 must be big enough so that the general
 		fields written below fit on the undo log page */

tests/mysql_client_test.c

@@ -21076,8 +21076,11 @@ static void test_mdev19838()
       " VALUES "
       "(0x1111111111111111)", -1);
 
-    /* Expecting an error if parameters are sent */
+    /*
-    DIE_UNLESS(rc != 0 || paramCount == 0);
+      We allow junk at the end of the packet in case of
+      no parameters. So it will succeed.
+    */
+    DIE_UNLESS(rc == 0);
   }
 
   mysql_stmt_close(stmt);