tree acffba18678cc48ddafdfa33ce94ee8812d47738
parent 6f9abc54eb23a21087004510742f631a6192a523
author Alexey Serbin <alexey@apache.org> 1698277101 -0700
committer Alexey Serbin <alexey@apache.org> 1699108515 +0000

[clock] KUDU-3521 fix crash when clock is synchronized by PTPd

There was an earlier attempt to address the issue [1], but the fix
hasn't received +2 since there was not enough evidence behind the
root cause analysis.  With the report on #kudu-general Slack
channel [2], from the analysis of the code [3] it's easy to see there
isn't any other way to get such a manifestation of the issue but
a negative value for the 'maxerror' field of the 'timex' structure
returned by the ntp_adjtime()/adjtimex() system call.

The essence of the problem is that in Kudu the maximum error is supposed
to be a non-negative number.  This patch addresses the issue.

[1] https://gerrit.cloudera.org/#/c/12149/
[2] https://getkudu.slack.com/archives/C0CPXJ3CH/p1698246065354269
[3] https://github.com/apache/kudu/blob/04fdbd0974f4418295d57c0daa4b67de3e777a43/src/kudu/clock/hybrid_clock.cc#L627-L706

Change-Id: Ibbe1a50c4857b9742d2ffde35440d0dee082edc0
Reviewed-on: http://gerrit.cloudera.org:8080/20626
Tested-by: Kudu Jenkins
Reviewed-by: Yingchun Lai <laiyingchun@apache.org>
Reviewed-by: Abhishek Chennaka <achennaka@cloudera.com>
(cherry picked from commit 4859d290277bf36f0bd84891c4764194c2cf9521)
  Conflicts:
    src/kudu/clock/system_ntp.cc
Reviewed-on: http://gerrit.cloudera.org:8080/20650