Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 16 Oct 2007 14:06:33 -0500
From:      Dan Nelson <dnelson@allantgroup.com>
To:        Kris Kennaway <kris@freebsd.org>
Cc:        freebsd-net@freebsd.org, freebsd-current@freebsd.org, Ivan Voras <ivoras@freebsd.org>
Subject:   Re: Panic in arpresolve->rt_check?
Message-ID:  <20071016190633.GA77224@dan.emsphone.com>
In-Reply-To: <20071016163123.GA22599@dan.emsphone.com>
References:  <fc89en$fc2$1@sea.gmane.org> <20070912172752.GA13960@dan.emsphone.com> <fc9ce3$jps$1@sea.gmane.org> <200710101615.48760.jhb@freebsd.org> <20071012143800.GA76105@dan.emsphone.com> <470F9211.8010604@FreeBSD.org> <20071016163123.GA22599@dan.emsphone.com>

next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Oct 16), Dan Nelson said:
> In the last episode (Oct 12), Kris Kennaway said:
> > Dan Nelson wrote:
> >> In the last episode (Oct 10), John Baldwin said:
> >>> On Wednesday 12 September 2007 02:50:37 pm Ivan Voras wrote:
> >>>> Dan Nelson wrote:
> >>>>> The same panic was also reported for 6.2 via PR 107865 and PR
> >>>>> 112490.  112490 included a workaround patch (I haven't tried it;
> >>>>> just found it).
> >>>>
> >>>> The proposed patch in kern/112490 looks trivial but someone who
> >>>> knows more about net locking should check it out. Unfortunately it
> >>>> lacks context and I don't know the code in question to apply it
> >>>> safely on a production machine :(
> >>>
> >>> I also get panics with what appears to be a double free of
> >>> rt_gwroute in rtexpunge(), so I think while this PR may help some
> >>> with figuring out the problem, I'm not sure it solves the root bug.
> >>> 
> >>> Hmm, possibly try this patch:
> >>
> >> This makes the panics more frequent on my machine, actually :)
> > 
> > Since you can reproduce this frequently the best thing might be to
> > instrument all the route handling with KTR so that you can do
> > post-mortem and try to figure out where the double-free or missing
> > reference happened.
> 
> I've added some KTR debugging (why are the macros named CTR* instead of
> KTR* ? ) and I think I've got the problem nailed down, but I don't know
> anything about networking so I don't know what the solution is.

.. and then I notice that yesterday John updated PR 112490 with a patch
that looks like it'll fix the problem, just to make me look silly today
:)

-- 
	Dan Nelson
	dnelson@allantgroup.com



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20071016190633.GA77224>