[openib-general] Re: dapl_ep_connect problems

[James Lentini]

On Mon, 12 Sep 2005, Hal Rosenstock wrote:

> On Mon, 2005-09-12 at 13:58, James Lentini wrote:
> > On Mon, 12 Sep 2005, Aniruddha Bohra wrote:
> > 
> > > Hi
> > >    I checked the code and it seems there was indeed a problem with that.
> > > I changed the code and now it posts the connect request and does not
> > > get any event. The ep_status is DAT_EP_STATE_CONNECT_PENDING.
> > > I am trying now with dapltest to see if it is a problem with my server
> > > (netapp filer NFSoRDMA) or the Open IB stack.
> > > 
> > > Thanks for your help. If you have any idea about some special 
> > > configuration required for the connection, I would really appreciate 
> > > your help. Is there any way to see the requests similar to tcpdump?
> > 
> > I believe you've run into an ATS issue. The ATS implementations in 
> > OnTap and OpenIB were done before the ATS specification was drafted in 
> > the DAT Collaborative.
> > 
> > The interoperability problem stems from the fact that OnTap ATS 
> > records and OpenIB ATS records use a different default value for the 
> > PKey field. When the issue was discussed in the DAT Collaborative, it 
> > was decided that the "default PKey value", 0xFF, should be the default 
>                                              ^^^^
>                                              0xFFFF
> 
> > for this field. This is what OpenIB is using. Your version of OnTap 
> > needs an update for this.
> > 
> > The quick fix is to modify OpenIB to use a default value of 0:
> > 
> > 
> > Index: core/at.c
> > ===================================================================
> > --- core/at.c	(revision 3375)
> > +++ core/at.c	(working copy)
> > @@ -95,6 +95,9 @@ static void build_ats_req(struct ib_sa_s
> >  {
> >  	struct ib_sa_ats_rec *ats;
> >  
> > +	/* FIXME Filer interop change */
> > +	pkey = 0;
> > +
> >  	memset(rec, 0, sizeof *rec);
> >  
> >  	rec->id = IB_ATS_SERVICE_ID;
> > 
> > 
> > The long term solution will be to give you an updated version of OnTap 
> > that uses the new default value. Let's work directly with one 
> > another on that since it is not an OpenIB issue.
> 
> Did you try this change ?

It works for our kernel NFS-RDMA client. 

Does IBAT use a different code path for creating ATS records if 
userspace access is enabled?