Re: LRO disable warnings on kernel 2.6.38

[Eric Dumazet <eric.dumazet@gmail.com>]

Le lundi 21 mars 2011 à 10:45 +0100, Eric Dumazet a écrit :
> Le lundi 21 mars 2011 à 10:21 +0100, Jesper Dangaard Brouer a écrit :
> > On Fri, 2011-03-18 at 09:18 -0700, Alexander Duyck wrote:
> > > On 3/18/2011 4:12 AM, Jesper Dangaard Brouer wrote:
> > > > Hi
> > > >
> > > > I'm seeing the LRO disable warnings using kernel 2.6.38:
> > [...]
> > > >
> > > The error doesn't make any sense for igb to be triggering since it 
> > > doesn't support setting the NETIF_F_LRO flag in the 2.6.38 kernel.
> > > 
> > > By any chance are there any ixgbe or other interfaces in the system?  I 
> > > would suspect the error to come from a driver that at least contains the 
> > > NETIF_F_LRO flag.
> > 
> > The servers actually also have a four port semi-build in NIC (its a PCIe
> > slot with an extra connector, most likely for controlling the LEDs).  I
> > don't use that NIC as it (1) caused kernel panics on 2.6.35, (2) needs a
> > firmware blob, (3) reading through the driver code (at some point in
> > time) they didn't implement multiqueue support correctly.
> > 
> > So lets blame that driver ;-)
> > 
> > lspci-info:
> >  Ethernet controller: NetXen Incorporated NX3031 Multifunction 1/10-Gigabit Server Adapter (rev 42)
> > 
> > driver info via ethtool:
> > # ethtool -i eth01
> >  driver: netxen_nic
> >  version: 4.0.75
> >  firmware-version: 4.0.530
> >  bus-info: 0000:06:00.3
> > 
> > The strange part is that my pre-prod server also have a netxen_nic, but
> > it does not result in a WARN being tricked... 
> > 
> > The pre-prod server do have a different firmware version.
> > # ethtool -i eth01
> >  driver: netxen_nic
> >  version: 4.0.75
> >  firmware-version: 4.0.406
> >  bus-info: 0000:06:00.0
> > 
> > (I have pulled the NIC out of some of the prod server, due to the risk
> > of a kernel panic on the old kernel.  As operations have taken over the
> > deployment process, these NICs are still in.  Guess I'll ask them to
> > blacklist the driver, so they don't see the warn stacktrace, they get so
> > nervous when they see stuff like that ;-))
> > 
> 
> Well, this warning can be ignored since these NIC dont receive packets
> to be forwarded in your setup.
> 
> I would say netxen_nic_set_flags() is buggy : It rejects data if other
> flag than ETH_FLAG_LRO is set.
> 
> if (data & ~ETH_FLAG_LRO)
> 	return -EINVAL;
> 
> Brought by commit ef2519b1dd39940 (netxen: fail when try to setup
> unsupported features) later corrected by commit 97d1935a61b7fe7a65f98f
> (Make ethtool_ops::set_flags() return -EINVAL for unsupported flags)
> 
> Since this drivers asserts NETIF_F_HW_VLAN_TX (mirroring
> ETH_FLAG_TXVLAN), ethtool_op_get_flags() can return more than
> ETH_FLAG_LRO.
> 
> dev_disable_lro() then calls netxen_nic_set_flags() with ETH_FLAG_TXVLAN
> -> -EINVAL, and ETH_FLAG_LRO stay ORed in dev->features -> WARNING
> 
> 
> 
> 

Couly you please send us the result of "ethtool -k eth01" to make sure
its the problem ?

Make sure your ethtool version includes these bits :
# ethtool -k eth0
Offload parameters for eth0:
...
large-receive-offload: off
rx-vlan-offload: on
tx-vlan-offload: on
ntuple-filters: off
receive-hashing: off


Thanks