Re: [PATCH 1/3] dma-mapping: remove the default map_resource implementation

2019-01-14 Thread Christoph Hellwig
On Mon, Jan 14, 2019 at 01:12:33PM +, Robin Murphy wrote: > Ignoring the offset was kind of intentional there, because at the time I > was primarily thinking about it in terms of the Keystone 2 platform where > the peripherals are all in the same place (0-2GB) in both the bus and CPU > physi

Re: [PATCH 1/3] dma-mapping: remove the default map_resource implementation

2019-01-14 Thread Robin Murphy
On 11/01/2019 18:17, Christoph Hellwig wrote: Just returning the physical address when not map_resource method is present is highly dangerous as it doesn't take any offset in the direct mapping into account and does the completely wrong thing for IOMMUs. Instead provide a proper implementation i