From mboxrd@z Thu Jan  1 00:00:00 1970
From: stephen mulcahy <smulcahy@gmail.com>
Subject: Re: forcedeth driver hangs under heavy load
Date: Tue, 13 Apr 2010 12:00:24 +0100
Message-ID: <4BC44EC8.1010104@gmail.com>
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Cc: netdev <netdev@vger.kernel.org>,
	Ben Hutchings <ben@decadent.org.uk>,
	Ayaz Abdulla <aabdulla@nvidia.com>, 572201@bugs.debian.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet wrote:
> Le mardi 13 avril 2010 =C3=A0 11:03 +0100, stephen mulcahy a =C3=A9cr=
it :
>> Eric Dumazet wrote:
>>> OK it seems forcedeth has problem with checksums ?
>>>
>>> Try to change "ethtool -k eth0" settings ?
>>>
>>> ethtool -K eth0 tso off tx off
>> Yes, that makes an unresponsive system responsive again immediately,=
 nice!
>>
>> Should the driver default to disabling this until we problem is corr=
ected?
>>
>> -stephen
>=20
> Both flags need to be disabled, or only one is OK ?

ethtool -K eth0 tx off

fixes the problem (without tso)

but running

ethtool -k eth0
Offload parameters for eth0:
rx-checksumming: on
tx-checksumming: off
scatter-gather: off
tcp-segmentation-offload: off
udp-fragmentation-offload: off
generic-segmentation-offload: on
generic-receive-offload: off
large-receive-offload: off

seems to indicate that tso is also disabled by this - does that sound=20
correct?

-stephen