Index: mysql-5.7.5-m15/sql/binlog.h
===================================================================
--- mysql-5.7.5-m15.orig/sql/binlog.h
+++ mysql-5.7.5-m15/sql/binlog.h
@@ -323,7 +323,6 @@ class MYSQL_BIN_LOG: public TC_LOG
   char db[NAME_LEN + 1];
   bool write_error, inited;
   IO_CACHE log_file;
-  volatile enum_log_state log_state;
   const enum cache_type io_cache_type;
 #ifdef HAVE_PSI_INTERFACE
   /** Instrumentation key to use for file io in @c log_file */
@@ -480,7 +479,7 @@ class MYSQL_BIN_LOG: public TC_LOG
 public:
   const char *generate_name(const char *log_name, const char *suffix,
                             char *buff);
-  bool is_open() const { return log_state != LOG_CLOSED; }
+  bool is_open() { return my_atomic_load32(&log_state) != LOG_CLOSED; }
 
   /* This is relay log */
   bool is_relay_log;
@@ -615,6 +614,8 @@ public:
     previous_gtid_set_relaylog= previous_gtid_set_param;
   }
 private:
+  int32 log_state; /* atomic enum_log_state */
+
   /* The prevoius gtid set in relay log. */
   Gtid_set* previous_gtid_set_relaylog;
 
Index: mysql-5.7.5-m15/sql/binlog.cc
===================================================================
--- mysql-5.7.5-m15.orig/sql/binlog.cc
+++ mysql-5.7.5-m15/sql/binlog.cc
@@ -2551,7 +2551,7 @@ bool mysql_show_binlog_events(THD* thd)
 MYSQL_BIN_LOG::MYSQL_BIN_LOG(uint *sync_period,
                              enum cache_type io_cache_type_arg)
   :name(NULL), write_error(false), inited(false),
-   log_state(LOG_CLOSED), io_cache_type(io_cache_type_arg),
+   io_cache_type(io_cache_type_arg),
 #ifdef HAVE_PSI_INTERFACE
    m_key_LOCK_log(key_LOG_LOCK_log),
 #endif
@@ -2563,6 +2563,7 @@ MYSQL_BIN_LOG::MYSQL_BIN_LOG(uint *sync_
    relay_log_checksum_alg(BINLOG_CHECKSUM_ALG_UNDEF),
    previous_gtid_set_relaylog(0)
 {
+  my_atomic_store32(&log_state, LOG_CLOSED);
   /*
     We don't want to initialize locks here as such initialization depends on
     safe_mutex (when using safe_mutex) which depends on MY_INIT(), which is
@@ -2902,7 +2903,7 @@ bool MYSQL_BIN_LOG::open(
                     MYF(MY_WME | MY_NABP | MY_WAIT_IF_FULL)))
     goto err;
 
-  log_state= LOG_OPENED;
+  my_atomic_store32(&log_state, LOG_OPENED);
   DBUG_RETURN(0);
 
 err:
@@ -2933,7 +2934,7 @@ err:
   end_io_cache(&log_file);
   my_free(name);
   name= NULL;
-  log_state= LOG_CLOSED;
+  my_atomic_store32(&log_state, LOG_CLOSED);
   DBUG_RETURN(1);
 }
 
@@ -3801,7 +3802,7 @@ bool MYSQL_BIN_LOG::open_binlog(const ch
 #endif
   }
 
-  log_state= LOG_OPENED;
+  my_atomic_store32(&log_state, LOG_OPENED);
 
 #ifdef HAVE_REPLICATION
   close_purge_index_file();
@@ -3820,7 +3821,7 @@ err:
   end_io_cache(&index_file);
   my_free(name);
   name= NULL;
-  log_state= LOG_CLOSED;
+  my_atomic_store32(&log_state, LOG_CLOSED);
   if (binlogging_impossible_mode == ABORT_SERVER)
   {
     THD *thd= current_thd;
@@ -6601,7 +6602,7 @@ void MYSQL_BIN_LOG::close(uint exiting)
 {					// One can't set log_type here!
   DBUG_ENTER("MYSQL_BIN_LOG::close");
   DBUG_PRINT("enter",("exiting: %d", (int) exiting));
-  if (log_state == LOG_OPENED)
+  if (my_atomic_load32(&log_state) == LOG_OPENED)
   {
 #ifdef HAVE_REPLICATION
     if ((exiting & LOG_CLOSE_STOP_EVENT) != 0)
@@ -6636,7 +6637,7 @@ void MYSQL_BIN_LOG::close(uint exiting)
     }
 
     /* this will cleanup IO_CACHE, sync and close the file */
-    if (log_state == LOG_OPENED)
+    if (my_atomic_load32(&log_state) == LOG_OPENED)
     {
       end_io_cache(&log_file);
 
@@ -6657,7 +6658,7 @@ void MYSQL_BIN_LOG::close(uint exiting)
       }
     }
 
-    log_state= (exiting & LOG_CLOSE_TO_BE_OPENED) ? LOG_TO_BE_OPENED : LOG_CLOSED;
+    my_atomic_store32(&log_state, (exiting & LOG_CLOSE_TO_BE_OPENED) ? LOG_TO_BE_OPENED : LOG_CLOSED);
     my_free(name);
     name= NULL;
   }
@@ -6678,7 +6679,7 @@ void MYSQL_BIN_LOG::close(uint exiting)
                       errno, my_strerror(errbuf, sizeof(errbuf), errno));
     }
   }
-  log_state= (exiting & LOG_CLOSE_TO_BE_OPENED) ? LOG_TO_BE_OPENED : LOG_CLOSED;
+  my_atomic_store32(&log_state, (exiting & LOG_CLOSE_TO_BE_OPENED) ? LOG_TO_BE_OPENED : LOG_CLOSED);
   my_free(name);
   name= NULL;
   DBUG_VOID_RETURN;