Re: [PATCH] vmd: Stop overriding dma_map_ops

[Derrick, Jonathan]

On Mon, 2019-08-26 at 17:06 +0200, Christoph Hellwig wrote:
> With a little tweak to the intel-iommu code we should be able to work
> around the VMD mess for the requester IDs without having to create giant
> amounts of boilerplate DMA ops wrapping code.  The other advantage of
> this scheme is that we can respect the real DMA masks for the actual
> devices, and I bet it will only be a matter of time until we'll see the
> first DMA challeneged NVMe devices.
> 
> The only downside is that we can't offer vmd as a module given that
> intel-iommu calls into it.  But the driver only has about 700 lines
> of code, so this should not be a major issue.
If we're going to remove its ability to be a module, and given its
small size, could we make this default =y?

Otherwise we risk breaking platforms which have it enabled with OSVs
who miss enabling it


> 
> This also removes the leftover bits of the X86_DEV_DMA_OPS dma_map_ops
> registry.
> 
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> 

lgtm otherwise

Reviewed-by: Jon Derrick <jonathan.derrick@xxxxxxxxx>