Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()

Jason Gunthorpe
2022-04-06T17:41:10Z

On Wed, Apr 06, 2022 at 05:47:23PM +0200, Christoph Hellwig wrote:
> On Wed, Apr 06, 2022 at 11:14:46AM -0300, Jason Gunthorpe wrote:
> > Really? It is the only condition that dma_info_to_prot() tests to
> > decide of IOMMU_CACHE is used or not, so you are saying that there is
> > a condition where a device can be attached to an iommu_domain and
> > dev_is_dma_coherent() returns the wrong information? How does
> > dma-iommu.c safely use it then?
>
> arm does not use dma-iommu.c

Oh. I did not know that. Thanks

Jason