[Nouveau] kernel spew from nouveau/ swiotlb

[Mike Galbraith]

On Thu, 2018-05-10 at 10:31 -0400, Jerome Glisse wrote:
> 
> Could you bisect ? I would love to point finger upstream to the DMA
> folk who made changes to that API without testing with GPU.

Rummaging a bit, it might be...

nouveau_bo_new()
...
ttm_dma_pool_alloc_new_pages()
  dma_alloc_attrs()
    ops->alloc() == x86_swiotlb_alloc_coherent()
    x86_swiotlb_alloc_coherent() flags |= __GFP_NOWARN;
      swiotlb_alloc_coherent(..flags)
        swiotlb_alloc_coherent(..flags) attrs = (flags & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0;
          swiotlb_alloc_buffer(..attr)
            swiotlb_alloc_buffer(..0)  <== hm, pass zero instead of attr?
              swiotlb_tbl_map_single() gripeage

...that?

	-Mike