From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tim Hartrick <tim@edgecast.com>
Subject: Re: crash in tcp_fragment
Date: Mon, 27 Feb 2012 16:29:52 -0700
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To: Ilpo =?ISO-8859-1?Q?J=E4rvinen?= <ilpo.jarvinen@helsinki.fi>
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Ilpo,

Thanks for the answers.  This gives me some clarity on how to address
the problem.


Tim Hartrick

On Tue, 2012-02-28 at 01:18 +0200, Ilpo J=C3=A4rvinen wrote:
> On Sun, 26 Feb 2012, Tim Hartrick wrote:
>=20
> > 	We have been seeing the crash cited below on a number of our syste=
ms
> > running kernel version 2.6.34, 2.6.36 and 2.6.38 using a number of
> > different GigE controllers.  I note that commit
> > 2fceec13375e5d98ef033c6b0ee03943fc460950 introduced a band-aid for =
the
> > problem by replacing the BUG_ON() to a WARN().  I have two question=
s
> > related to this.
> >=20
> > 1) Is there a fix for the root cause?  Can I get a pointer to the c=
ommit
> > that claims to address the root cause?
>=20
> There have been multiple fixes recently on the counters which this co=
de=20
> depends on, however, nobody has afaict fully analyzed what else those=
=20
> fixed.
>=20
> > 2) Will disabling GSO/TSO make the problem go away?  That is, is
> > something related to GSO/TSO at the root of the problem?
>=20
> Very likely.
>=20