Re: Segmentation fault running ntpd

On Fri, Oct 30, 2015 at 09:42:07AM +0100, Dag-Erling Smørgrav wrote:
> David Wolfskill <david_at_catwhisker.org> writes:
> > ...
> > bound to 172.17.1.245 -- renewal in 43200 seconds.
> > pid 544 (ntpd), uid 0: exited on signal 11 (core dumped)
> > Starting Network: lo0 em0 iwn0 lagg0.
> > ...
> 
> Did you find a solution?  I'm wondering if the ntpd problems people are
> reporting on freebsd-security_at_ are related.  I vaguely recall hearing
> that this had been traced to a pthread bug, but can't find anything
> about it in commit logs or mailing list archives.
> ....

I don't recall finding "a solution" per se; that said, I also don't
recall seeing an occurrence of the above for enough time that I'm not
sure when I sent that message. :-}

As a reality check:

g1-252(11.0-C)[1] ls -lT /*.core
-rw-r--r--  1 root  wheel  13783040 Aug 18 04:19:03 2015 /ntpd.core
g1-252(11.0-C)[2] 

So -- among other points -- my last sighting of whatever was causing
that was the day I built:

FreeBSD 11.0-CURRENT #157  r286880M/286880:1100079: Tue Aug 18 04:45:25 PDT 2015     root_at_g1-252.catwhisker.org:/common/S4/obj/usr/src/sys/CANARY  amd64

Note that the machines where I run head get updated daily (unless
there's enough of a problem with head that I can't build it or can't
boot it (and I'm unable to circumvent the issue within a reasonable
time)) -- and while I do attempt to run ntpd on the machines, the above
failure is more "annoying" than "crippling" in my particular case.

And I'm presently running:

FreeBSD 11.0-CURRENT #227  r290138M/290138:1100084: Thu Oct 29 05:12:58 PDT 2015     root_at_g1-252.catwhisker.org:/common/S4/obj/usr/src/sys/CANARY  amd64

and building head _at_r290190 as I type.

And FWIW, I *suspect* that one of the issues involved (in my case)
was a ... lack of determinism ... in events involving getting the
(wireless) network connectivity into a usable state as part of the
initial transition to multi-user mode.  (I only have evidence at
the moment of the issue on my laptop; my build machine, which only
uses a wired NIC, has no /ntpd.core file.  It and my laptop are updated
pretty much in lock-step; it runs a completely GENERIC kernel, while
the laptop runs a modestly customized one based on GENERIC.)

Peace,
david
-- 
David H. Wolfskill				david_at_catwhisker.org
Those who would murder in the name of God or prophet are blasphemous cowards.

See http://www.catwhisker.org/~david/publickey.gpg for my public key.