WARNING: ThreadSanitizer: lock-order-inversion (potential deadlock) 
  Cycle in lock order graph: M1 (0x000000000000) => M2 (0x000000000000) => M3 (0x000000000000) => M1

  Mutex M2 acquired here while holding mutex M1 in thread T1:
    #0 pthread_mutex_lock <null>
    #1 dns_view_find lib/dns/view.c:1037:2
    #2 dbfind_name lib/dns/adb.c:3833:11
    #3 dns_adb_createfind lib/dns/adb.c:3155:12
    #4 findname lib/dns/resolver.c:3497:11
    #5 fctx_getaddresses lib/dns/resolver.c:3808:3
    #6 fctx_try lib/dns/resolver.c:4197:12
    #7 fctx_timeout lib/dns/resolver.c:4633:4
    #8 dispatch lib/isc/task.c:1152:7
    #9 run lib/isc/task.c:1344:2

  Mutex M1 previously acquired by the same thread here:
    #0 pthread_mutex_lock <null>
    #1 find_name_and_lock lib/dns/adb.c:2117:3
    #2 dns_adb_createfind lib/dns/adb.c:3085:12
    #3 findname lib/dns/resolver.c:3497:11
    #4 fctx_getaddresses lib/dns/resolver.c:3808:3
    #5 fctx_try lib/dns/resolver.c:4197:12
    #6 fctx_timeout lib/dns/resolver.c:4633:4
    #7 dispatch lib/isc/task.c:1152:7
    #8 run lib/isc/task.c:1344:2

  Mutex M3 acquired here while holding mutex M2 in thread T1:
    #0 pthread_mutex_lock <null>
    #1 dns_adb_shutdown lib/dns/adb.c:2977:2
    #2 view_flushanddetach lib/dns/view.c:635:4
    #3 dns_view_detach lib/dns/view.c:689:2
    #4 qctx_destroy lib/ns/query.c:5152:2
    #5 fetch_callback lib/ns/query.c:5749:3
    #6 dispatch lib/isc/task.c:1152:7
    #7 run lib/isc/task.c:1344:2

  Mutex M2 previously acquired by the same thread here:
    #0 pthread_mutex_lock <null>
    #1 view_flushanddetach lib/dns/view.c:630:3
    #2 dns_view_detach lib/dns/view.c:689:2
    #3 qctx_destroy lib/ns/query.c:5152:2
    #4 fetch_callback lib/ns/query.c:5749:3
    #5 dispatch lib/isc/task.c:1152:7
    #6 run lib/isc/task.c:1344:2

  Mutex M1 acquired here while holding mutex M3 in thread T1:
    #0 pthread_mutex_lock <null>
    #1 shutdown_names lib/dns/adb.c:1296:3
    #2 shutdown_stage2 lib/dns/adb.c:2961:8
    #3 dispatch lib/isc/task.c:1152:7
    #4 run lib/isc/task.c:1344:2

  Mutex M3 previously acquired by the same thread here:
    #0 pthread_mutex_lock <null>
    #1 shutdown_stage2 lib/dns/adb.c:2958:2
    #2 dispatch lib/isc/task.c:1152:7
    #3 run lib/isc/task.c:1344:2

  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

SUMMARY: ThreadSanitizer: lock-order-inversion (potential deadlock) in pthread_mutex_lock