On Thu, 2016-01-28 at 18:31 -0800, Andy Lutomirski wrote: > > To everyone else: we've waffled on this for way too long.  I think > we should to get DMA API implementation in with a conservative > policy like this rather than waiting until we achieve perfection. > I'm tired of carrying these patches around. Yeah, do it. However,,, shouldn't the generic no-op DMA ops be checking the dma_mask of the device and bitching if it can't reach the address in question? Also, wasn't Christoph looking at making per-device DMA ops more generic instead of an 'archdata' thing on basically every platform? Or did I just imagine that part? Not that I'm suggesting you make the s390 patch wait for that *instead* of using archdata there, mind you. But I was kind of planning to let the dust settle on this lot before I sort out the theoretical-except- in-simulation issues with VT-d IOMMU covering *some* devices but not all. -- David Woodhouse Open Source Technology Centre David.Woodhouse@intel.com Intel Corporation