From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: 2.6.34: Problem with UDP traffic on lo + poll(?)
Date: Tue, 07 Sep 2010 23:39:04 +0200
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Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org
To: Krzysztof =?UTF-8?Q?Ol=C4=99dzki?= <ole@ans.pl>
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Le mardi 07 septembre 2010 =C3=A0 23:28 +0200, Krzysztof Ol=C4=99dzki a=
 =C3=A9crit :

> With the above patch I'm no longer able to reproduce the problem. Tha=
nks!
>=20
> Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl>
>=20

Thanks a lot !

> BTW: why it takes so long to trigger this bug and it is only possible=
=20
> over a loopback interface?

Its a bit tricky : You need at least 10 sockets linked in a particular
hash chain.

To check this, you can :

cat /proc/net/udp

maybe you have many sockets on port 123 or 53 ?

And about loopback, I have no idea... I am pretty sure I can trigger th=
e
bug with other interfaces.