> > I've been meaning to track down the bnx2 iscsi offload patch to look
> > and see if this issue is addressed, since the same problem seems to
> > exist: it seems an iscsi connection and a main stack tcp connection
> > might share the same 4-tuple unless something is done to avoid that
> > happening.
> iSCSI does not do passive listens, only active connections to the
> target. But you're right, the port space is still shared between iSCSI
> and the main stack. We currently rely on user apps binding to the main
> stack to reserve certain ephemeral ports, and telling the iSCSI driver
> which ports to use.
Got it... I wasn't thinking that clearly, but it is clear that a full
4-tuple collision with only active connections is quite unlikely. I
guess you would have to make both an offloaded and a non-offloaded
iSCSI connection to the same target and get really unlucky with
ephemeral port allocation. So in practice I guess it's not an issue
at all with your driver yet.
However, do you have any plans to support iSCSI offload for targets?
Also, looking at the first CNIC patch, I can't help but notice that
you seem to have at least some support for iWARP there. How does the
CNIC look? Does it share the same interface/addresses as the
non-offload NIC, or does it create a completely separate netdevice?
I want to make sure that whatever solution we come up with for cxgb3
doesn't cause problems for you. And of course if you have a better
idea than what Steve has come up with, that would be great :)
- R.
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