Bug #38816: kill + flush tables with read lock + stored

procedures causes crashes!

The problem of that bugreport was mostly fixed by the
patch for bug 38691.
However, attached test case focused on another crash or
valgrind warning problem: SHOW PROCESSLIST query accesses
freed memory of SP instruction that run in a parallel
connection.

Changes of thd->query/thd->query_length in dangerous
places have been guarded with the per-thread
LOCK_thd_data mutex (the THD::LOCK_delete mutex has been
renamed to THD::LOCK_thd_data).


sql/ha_myisam.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  Modification of THD::query/query_length has been guarded
  with the a THD::set_query() method call/LOCK_thd_data
  mutex.
  Unnecessary locking with the global LOCK_thread_count
  mutex has been removed.
sql/log_event.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  Modification of THD::query/query_length has been guarded
  with the THD::set_query()) method call/LOCK_thd_data
  mutex.
sql/slave.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  Modification of THD::query/query_length has been guarded
  with the THD::set_query() method call/LOCK_thd_data mutex.
  
  The THD::LOCK_delete mutex has been renamed to
  THD::LOCK_thd_data.
sql/sp_head.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  Modification of THD::query/query_length has been guarded
  with the a THD::set_query() method call/LOCK_thd_data
  mutex.
sql/sql_class.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  The new THD::LOCK_thd_data mutex and THD::set_query()
  method has been added to guard modifications of THD::query/
  THD::query_length fields, also the Statement::set_statement()
  method has been overloaded in the THD class.
  
  The THD::LOCK_delete mutex has been renamed to
  THD::LOCK_thd_data.
sql/sql_class.h:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  The new THD::LOCK_thd_data mutex and THD::set_query()
  method has been added to guard modifications of THD::query/
  THD::query_length fields, also the Statement::set_statement()
  method has been overloaded in the THD class.
  
  The THD::LOCK_delete mutex has been renamed to
  THD::LOCK_thd_data.
sql/sql_insert.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  Modification of THD::query/query_length has been guarded
  with the a THD::set_query() method call/LOCK_thd_data
  mutex.
sql/sql_parse.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  Modification of THD::query/query_length has been guarded
  with the a THD::set_query() method call/LOCK_thd_data mutex.
sql/sql_repl.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  The THD::LOCK_delete mutex has been renamed to
  THD::LOCK_thd_data.
sql/sql_show.cc:
  Bug #38816: kill + flush tables with read lock + stored
              procedures causes crashes!
  
  Inter-thread read of THD::query/query_length field has
  been protected with a new per-thread LOCK_thd_data
  mutex in the mysqld_list_processes function.
This commit is contained in:
Gleb Shchepa 2009-07-24 20:58:58 +05:00
commit dc0a87fdc2
10 changed files with 100 additions and 99 deletions

View file

@ -1044,7 +1044,7 @@ void kill_zombie_dump_threads(uint32 slave_server_id)
if (tmp->command == COM_BINLOG_DUMP &&
tmp->server_id == slave_server_id)
{
pthread_mutex_lock(&tmp->LOCK_delete); // Lock from delete
pthread_mutex_lock(&tmp->LOCK_thd_data); // Lock from delete
break;
}
}
@ -1057,7 +1057,7 @@ void kill_zombie_dump_threads(uint32 slave_server_id)
again. We just to do kill the thread ourselves.
*/
tmp->awake(THD::KILL_QUERY);
pthread_mutex_unlock(&tmp->LOCK_delete);
pthread_mutex_unlock(&tmp->LOCK_thd_data);
}
}