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

  Mutex M2 acquired here while holding mutex M1 in thread T1:
    #0 pthread_mutex_lock <null>
    #1 dns_view_findzonecut lib/dns/view.c:1310:2
    #2 fctx_create lib/dns/resolver.c:5070:13
    #3 dns_resolver_createfetch lib/dns/resolver.c:10813:12
    #4 fetch_name lib/dns/adb.c:4194:11
    #5 dns_adb_createfind lib/dns/adb.c:3256:7
    #6 findname lib/dns/resolver.c:3497:11
    #7 fctx_getaddresses lib/dns/resolver.c:3808:3
    #8 fctx_try lib/dns/resolver.c:4197:12
    #9 fctx_timeout lib/dns/resolver.c:4633:4
    #10 dispatch lib/isc/task.c:1152:7
    #11 run lib/isc/task.c:1344:2

  Mutex M1 previously acquired by the same thread here:
    #0 pthread_mutex_lock <null>
    #1 dns_resolver_createfetch lib/dns/resolver.c:10767:2
    #2 fetch_name lib/dns/adb.c:4194:11
    #3 dns_adb_createfind lib/dns/adb.c:3256:7
    #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 acquired here while holding mutex M2 in thread T1:
    #0 pthread_mutex_lock <null>
    #1 dns_resolver_shutdown lib/dns/resolver.c:10530:4
    #2 view_flushanddetach lib/dns/view.c:632:4
    #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

  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