netdev - Re: IPv6 path MTU discovery broken

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Message-ID: <20130928205131.GB20124@sesse.net>
Date:	Sat, 28 Sep 2013 22:51:31 +0200
From:	"Steinar H. Gunderson" <sgunderson@...foot.com>
To:	netdev@...r.kernel.org, edumazet@...gle.com
Subject: Re: IPv6 path MTU discovery broken

On Sat, Sep 28, 2013 at 10:33:18PM +0200, Hannes Frederic Sowa wrote:
>> Could this be related somehow to the packets coming from 2001:67c:29f4::31,
>> while the default route is to a link-local address? (An RPF issue?) This used
>> to work (although it was often flaky for me) in 3.10 and before. I can't
>> easily bisect, though, as I don't boot this machine too often.
> This looks like a bug and should definitely get fixed. There should be
> no RPF issue. May I have a look at your /proc/net/ipv6_route?

Hi,

I removed all the “weird” routes, and confirmed it fixed the problem.
However, upon adding them back again, the problem was still gone
(despite flushing the route cache).

This means that the issue has gone back to being intermittent, which is of
course the worst kind of bug to trace down. :-) I'll dump
/proc/net/ipv6_route and send you once I see the bug manifest itself again,
OK?

/* Steinar */
-- 
Homepage: http://www.sesse.net/
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