autobuild[sn-devel-144]: intermittent test failure detected

[autobuild]

The autobuild test system (on sn-devel-144) has detected an intermittent failing test in 
the current master tree.

The autobuild log of the failure is available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-07-31-1247/flakey.log

The failure seems to be in the "samba-nt4" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-07-31-1247/samba-nt4.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-07-31-1247/samba-nt4.stdout
  
The top commit at the time of the failure was:

commit 80c9219d6079532f31c4e415906a606d395af6e8
Author: Anoop C S <anoopcs at redhat.com>
Date:   Fri Jul 27 11:50:39 2018 +0530

    s3/locking: Fix assertion check on lock reference count
    
    lock_ref_count will always hold the old value prior to change. Thus it
    would mean that if lock_ref_count is 0 the new value is already -1 which
    is not expected here. Therefore it is better to make sure that it is
    always greater than 0 rather than >= 0.
    
    Signed-off-by: Anoop C S <anoopcs at redhat.com>
    Reviewed-by: Jeremy Allison <jra at samba.org>
    Reviewed-by: Andreas Schneider <asn at samba.org>
    
    Autobuild-User(master): Jeremy Allison <jra at samba.org>
    Autobuild-Date(master): Tue Jul 31 04:23:47 CEST 2018 on sn-devel-144

and the last 50 lines of the stdout log were:

[516(2402)/563 at 19m57s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_dc:local)
[517(2403)/563 at 19m57s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_dc:local)
[518(2404)/563 at 19m57s] samba.wbinfo_simple.change-secret.domain=$DOMAIN(nt4_dc:local)
[519(2405)/563 at 19m57s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_dc:local)
[520(2406)/563 at 19m57s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_dc:local)
[521(2407)/563 at 19m57s] samba.wbinfo_simple.domain-users(nt4_dc:local)
[522(2408)/563 at 19m57s] samba.wbinfo_simple.domain-groups(nt4_dc:local)
[523(2409)/563 at 19m57s] samba.wbinfo_simple.name-to-sid=$DC_USERNAME(nt4_dc:local)
[524(2410)/563 at 19m58s] samba.wbinfo_simple.name-to-sid=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[525(2411)/563 at 19m58s] samba.wbinfo_simple.user-info=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[526(2412)/563 at 19m58s] samba.wbinfo_simple.user-groups=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[527(2413)/563 at 19m58s] samba.wbinfo_simple.authenticate=$DOMAIN/$DC_USERNAME%$DC_PASSWORD(nt4_dc:local)
[528(2414)/563 at 19m58s] samba.wbinfo_simple.allocate-uid(nt4_dc:local)
[529(2415)/563 at 19m58s] samba.wbinfo_simple.allocate-gid(nt4_dc:local)
[530(2416)/563 at 19m58s] samba.wbinfo_sids2xids.(nt4_dc:local)(nt4_dc:local)
[531(2417)/563 at 20m7s] samba.ntlm_auth.diagnostics(nt4_dc:local)(nt4_dc:local)
[532(2418)/563 at 20m8s] samba.ntlm_auth.(nt4_dc:local)(nt4_dc:local)
[533(2437)/563 at 20m10s] samba.wbinfo_simple.ping(nt4_member:local)
[534(2438)/563 at 20m10s] samba.wbinfo_simple.separator(nt4_member:local)
[535(2439)/563 at 20m10s] samba.wbinfo_simple.own-domain(nt4_member:local)
[536(2440)/563 at 20m10s] samba.wbinfo_simple.all-domains(nt4_member:local)
[537(2441)/563 at 20m10s] samba.wbinfo_simple.trusted-domains(nt4_member:local)
[538(2442)/563 at 20m10s] samba.wbinfo_simple.domain-info=BUILTIN(nt4_member:local)
[539(2443)/563 at 20m11s] samba.wbinfo_simple.domain-info=$DOMAIN(nt4_member:local)
[540(2444)/563 at 20m11s] samba.wbinfo_simple.online-status(nt4_member:local)
[541(2445)/563 at 20m11s] samba.wbinfo_simple.online-status.domain=BUILTIN(nt4_member:local)
[542(2446)/563 at 20m11s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_member:local)
[543(2447)/563 at 20m11s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_member:local)
UNEXPECTED(failure): samba.wbinfo_simple.check-secret.domain=SAMBA-TEST.wbinfo(nt4_member:local)
REASON: Exception: Exception: wbcCheckTrustCredentials(SAMBA-TEST): error code was NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND (0xc0000233)
failed to call wbcCheckTrustCredentials: WBC_ERR_AUTH_ERROR
Could not check secret
checking the trust secret for domain SAMBA-TEST via RPC calls failed

FAILED (1 failures, 0 errors and 0 unexpected successes in 0 testsuites)

A summary with detailed information can be found in:
  ./bin/ab/summary
TOP 10 slowest tests
samba3.raw.notify(nt4_dc) -> 99
samba3.smb2.notify(nt4_dc) -> 79
samba3.rpc.samr.passwords.lockout(nt4_dc) -> 62
samba4.rpc.echo on ncacn_np with object(nt4_dc) -> 61
samba3.rpc.samr.passwords.pwdlastset(nt4_dc) -> 49
samba3.smb2.lease(nt4_dc) -> 44
samba3.smb2.oplock(nt4_dc) -> 42
samba3.raw.oplock(nt4_dc) -> 42
samba3.raw.search(nt4_dc) -> 35
samba3.raw.lock(nt4_dc) -> 33
ERROR: test failed with exit code 1