Re: A blast from the past - strange sysctl behavior

[Paul Goyette <paul%whooppee.com@localhost>]

On Mon, 5 Sep 2016, Paul Goyette wrote:

> Nearly a year ago, I posted [1] on the current-users list.  Since that time 
> I've been running with the attached patch, in an attempt to find out what was 
> going on.  And as is usually the case, the debug code didn't get triggered, 
> until now - 11 months later!
>
> I haven't had a chance to investigate in any detail, but the problem (and 
> associated KASSERT) occurred while starting firefox.  A bit more detail shows 
> that it was installing the sysctl tree for the sysv_ipc module.  However, 
> after the reboot I was able to successfully launch firefox without triggering 
> the KASSERT.
>
> If anyone has any clues about how this anomaly can happen (a newly created 
> sysctl node has a wrong parent), I'd love to hear them.  I am guessing that 
> there's some sort of locking botch in the sysctl code, however I haven't been 
> able to spot it.
>
>
> [1] https://mail-index.netbsd.org/current-users/2015/10/27/msg028285.html

FWIW, the KASSERT() triggered right after I had updated my amd64 kernel 
and userland from a July 4th 7.99.33 to a Sept. 5th 7.99.36.



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