On Wed, 03 Feb 2010 11:47:19 -0500
Michael Breuer [off-list ref] wrote:

Tracked this down. The status being returned is 0x3c0080 - good flow 
control packets. Nothing is actually being dropped (confirmed by packet 
trace on switch compared with packet trace on server).

I whipped up a trivial patch to not count these as dropped packets and 
will post to netdev.

I'm not really sure what the driver should be doing in this case, but 
resubmit seems to work.

Looks like a flow control negotiation issue. You probably turned off
flow control on the Linux side, but the switch is still doing flow
control.

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