Re: [PATCH v5 3/7] drivers: dma-coherent: Account dma_pfn_offset when used with device tree

[Christoph Hellwig]

On Tue, Jun 20, 2017 at 02:50:34PM +0100, Robin Murphy wrote:
> On 20/06/17 14:42, Christoph Hellwig wrote:
> > Wouldn't the smal patch below solve the same issue in a simple way?
> 
> That assumes that all devices accessing a shared pool will have the same
>  dma_pfn_offset as the first one, which cannot strictly be relied upon
> (even if it is highly likely in practice).

Which seems like another argument why the global pool should be
a different implementation / interface than the per-device dma
mapping helpers..