[ofa-general] Re: bonding & ipoib patches to support bonding of ipoib devices

[Michael S. Tsirkin]

> >>I just need a clarification on (2), can you educate me how can it 
> >>happen?
> >
> >Consider a specific neighbour. Can the following happen? If no, why not?
> >- a packet is sent through ib0, ipoib_neigh and ->ah are created
> >- bonding switches to ib1 for some reason
> >- before ipoib_neigh and ah are flushed, a new skb arrives. It is posted on
> >  ib1 with ah which belongs to ib0
> 
> oh well, this is very rare but possible. IB wise, what would happen on 
> this case to the device (ib1 in your example) QP? will this wrong ah 
> usage in the WR cause it get into the error case?

Hard to say, I think the behaviour is unspecified.
And even at the IPoIB level, note that at this point you are
locking tx_lock at ib1 but not at ib0, so both ipoib_neigh and ->ah
might disappear under your feet.

-- 
MST