[openib-general] Reserved L_Key API

[Michael S. Tsirkin]

Hello!
Quoting r. Grant Grundler (iod00d at hp.com) "Re: [openib-general] Reserved L_Key API":
> On Wed, Sep 15, 2004 at 08:42:53AM -0700, Roland Dreier wrote:
> >     Fabian> Are the ramifications of such an RKEY any worse than those
> >     Fabian> of locally attached DMA-capable adapters?
> 
> Not if one can guarantee it's well behaved.
> 
> >     Fabian> If your FC HBA
> >     Fabian> goes haywire and decides to write all over memory, there's
> >     Fabian> not much you can do.
> 
> That's not true. There are platforms that can isolate the FC and
> prevent the FC HBA from scribbling to anything the respective driver
> didn't previously get explicite write permission. ie we can guarantee
> the containment.

In such platforms, my understanding is you dont really need the rkey protection
in the HCA - the dma API will do this for you.