[openib-general] basic IB doubt

[Roland Dreier]

    glebn> So, before touching the data that was RDMAed into the
    glebn> buffer application should cache invalidate the buffer, is
    glebn> this even possible from user space? (Not on x86, but it
    glebn> isn't needed there.)

Yes, on any architecture that is not cache-coherent with PCI DMA, some
cache invalidation/flushing will be necessary.  And this probably
won't be possible from userspace if the cache is physically tagged.
(Are there any such architectures in real use, ie non-coherent with
PCI and physically tagged cache?)

 - R.