diff options
Diffstat (limited to 'sql/slave.cc')
| -rw-r--r-- | sql/slave.cc | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/sql/slave.cc b/sql/slave.cc index d58a3f549d8..572fafd58b5 100644 --- a/sql/slave.cc +++ b/sql/slave.cc @@ -3759,8 +3759,13 @@ err: mi->abort_slave= 0; mi->slave_running= 0; mi->io_thd= 0; - pthread_mutex_unlock(&mi->run_lock); + /* + Note: the order of the two following calls (first broadcast, then unlock) + is important. Otherwise a killer_thread can execute between the calls and + delete the mi structure leading to a crash! (see BUG#25306 for details) + */ pthread_cond_broadcast(&mi->stop_cond); // tell the world we are done + pthread_mutex_unlock(&mi->run_lock); #ifndef DBUG_OFF if (abort_slave_event_count && !events_till_abort) goto slave_begin; @@ -3978,8 +3983,13 @@ the slave SQL thread with \"SLAVE START\". We stopped at log \ THD_CHECK_SENTRY(thd); delete thd; pthread_mutex_unlock(&LOCK_thread_count); - pthread_cond_broadcast(&rli->stop_cond); + /* + Note: the order of the broadcast and unlock calls below (first broadcast, then unlock) + is important. Otherwise a killer_thread can execute between the calls and + delete the mi structure leading to a crash! (see BUG#25306 for details) + */ + pthread_cond_broadcast(&rli->stop_cond); #ifndef DBUG_OFF /* Bug #19938 Valgrind error (race) in handle_slave_sql() @@ -3987,9 +3997,8 @@ the slave SQL thread with \"SLAVE START\". We stopped at log \ */ const int eta= rli->events_till_abort; #endif - - // tell the world we are done - pthread_mutex_unlock(&rli->run_lock); + pthread_mutex_unlock(&rli->run_lock); // tell the world we are done + #ifndef DBUG_OFF // TODO: reconsider the code below if (abort_slave_event_count && !eta) goto slave_begin; |