TSAN error bin/named/controlconf.c related.

Job #1213042 failed for ced5041d:

WARNING: ThreadSanitizer: data race 
  Write of size 8 at 0x000000000001 by thread T1:
    #0 isc_nmhandle_detach lib/isc/netmgr/netmgr.c:1258:15
    #1 control_command bin/named/controlconf.c:388:3
    #2 dispatch lib/isc/task.c:1152:7
    #3 run lib/isc/task.c:1344:2

  Previous read of size 8 at 0x000000000001 by thread T2:
    #0 isc_nm_pauseread lib/isc/netmgr/netmgr.c:1449:33
    #1 recv_data lib/isccc/ccmsg.c:109:2
    #2 isc__nm_tcp_shutdown lib/isc/netmgr/tcp.c:1157:4
    #3 shutdown_walk_cb lib/isc/netmgr/netmgr.c:1515:3
    #4 uv_walk <null>
    #5 process_queue lib/isc/netmgr/netmgr.c:659:4
    #6 process_normal_queue lib/isc/netmgr/netmgr.c:582:10
    #7 process_queues lib/isc/netmgr/netmgr.c:590:8
    #8 async_cb lib/isc/netmgr/netmgr.c:548:2
    #9 <null> <null>

  Location is heap block of size 569 at 0x000000000016 allocated by thread T2:
    #0 malloc <null>
    #1 default_memalloc lib/isc/mem.c:713:8
    #2 mem_get lib/isc/mem.c:622:8
    #3 isc___mem_get lib/isc/mem.c:1044:9
    #4 isc__mem_get lib/isc/mem.c:2432:10
    #5 alloc_handle lib/isc/netmgr/netmgr.c:1076:3
    #6 isc__nmhandle_get lib/isc/netmgr/netmgr.c:1100:12
    #7 isc__nm_async_tcpchildaccept lib/isc/netmgr/tcp.c:486:11
    #8 process_queue lib/isc/netmgr/netmgr.c:624:4
    #9 process_normal_queue lib/isc/netmgr/netmgr.c:582:10
    #10 process_queues lib/isc/netmgr/netmgr.c:590:8
    #11 async_cb lib/isc/netmgr/netmgr.c:548:2
    #12 <null> <null>

  Thread T1 (running) created by main thread at:
    #0 pthread_create <null>
    #1 isc_thread_create lib/isc/pthreads/thread.c:73:8
    #2 isc_taskmgr_create lib/isc/task.c:1434:3
    #3 create_managers bin/named/main.c:915:11
    #4 setup bin/named/main.c:1223:11
    #5 main bin/named/main.c:1523:2

  Thread T2 (running) created by main thread at:
    #0 pthread_create <null>
    #1 isc_thread_create lib/isc/pthreads/thread.c:73:8
    #2 isc_nm_start lib/isc/netmgr/netmgr.c:232:3
    #3 create_managers bin/named/main.c:909:15
    #4 setup bin/named/main.c:1223:11
    #5 main bin/named/main.c:1523:2

SUMMARY: ThreadSanitizer: data race lib/isc/netmgr/netmgr.c:1258:15 in isc_nmhandle_detach