Re: 2.6.21.5 june 30th to july 1st date hang?

[Dave Jones <davej@redhat.com>]

On Tue, Jul 03, 2007 at 11:36:42AM -0400, Fortier,Vincent [Montreal] wrote:
 > > -----Message d'origine-----
 > > De : linux-kernel-owner@vger.kernel.org 
 > > [mailto:linux-kernel-owner@vger.kernel.org] De la part de 
 > > Arne Georg Gleditsch
 > > 
 > > Florian Attenberger <valdyn@gmail.com> writes:
 > > > yep, controlled by ntpd.
 > > > You're right according to
 > > > ftp://hpiers.obspm.fr/iers/bul/bulc/bulletinc.33
 > > > that event shouldn't have been there.
 > > 
 > > I'm not all that versed in ntp-ish, but it appears that the 
 > > leap second insertion should be propagated through the ntp protocol.
 > > Whether the leap second in question came from a ntp server 
 > > giving out wrong data or from a misinterpretation or bug in 
 > > ntpd is of course hard to say, but either way turning the 
 > > clock back is unlikely to reconstruct the circumstances.  An 
 > > interesting exercise might be to code up a small program to 
 > > call adjtimex with timex.status |= STA_INS, to see if this 
 > > can trigger the problem.  (The bogus leap second might be a 
 > > red herring entirely, of course...)
 > 
 > You are probably right, I did tried to reproduce the problem without
 > success...
 > 
 > Although it is wierd that it happend only on 2.6.21 kernels... It did
 > not happend on any of my workstations/servers running either 2.6.18 or
 > 2.6.20.  
 > 
 > Could dynticks be involved?

I saw it on a box that happened to have lockdep enabled.
(I run it everywhere thankfully).  This is what it looked like..
http://www.codemonkey.org.uk/junk/img_0421.jpg

	Dave

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