[openib-general] [PATCH ] RFC IB/cm do not track remote QPN in timewait state

[Michael S. Tsirkin]

Quoting r. Michael S. Tsirkin <mst at mellanox.co.il>:
> Subject: Re: [PATCH ] RFC IB/cm do not track remote QPN in timewait state
> 
> Quoting r. Sean Hefty <mshefty at ichips.intel.com>:
> > Subject: Re: [PATCH ] RFC IB/cm do not track remote QPN in timewait state
> > 
> > Michael S. Tsirkin wrote:
> > > And so can RTU, in which case again QP will be in RTR. So it seems
> > > lost CM packets aren't protected by timewait.
> > 
> > Maybe we just try to deal with this the best that we can and make the HCA
> > driver responsible for not re-allocating QPs for a duration of
> > local_ack_timeout once they've entered RTS.
> > 
> > If connections are made through the IB CM, it seems unlikely that stale
> > packets will float around the subnet longer than it takes to establish a new
> > connection.  We just need to be able to detect stale connections, which
> > requires that users use the CM when connecting.
> 
> Fair enough.

To clarify - I don't necessarily agree that stale packets are unlikely,
but I do agree that asking low level driver to prevent QPN from
being re-allocated for a duration of local_ack_timeout once QP
has entered RTS will be sufficient.

-- 
MST