On Thu, Nov 24, 2016 at 10:45:18AM +0100, Christian König wrote: > Am 24.11.2016 um 00:25 schrieb Jason Gunthorpe: > >There is certainly nothing about the hardware that cares > >about ZONE_DEVICE vs System memory. > Well that is clearly not so simple. When your ZONE_DEVICE pages describe a > PCI BAR and another PCI device initiates a DMA to this address the DMA > subsystem must be able to check if the interconnection really works.
I said the hardware doesn't care.. You are right, we still have an outstanding problem in Linux of how to generically DMA map a P2P address - which is a different issue from getting the P2P address from a __user pointer... Jason
