Re: [PATCH v2 3/3] iommu/io-pgtable-arm-v7s: Request DMA32 memory, and improve debugging

[Christopher Lameter]

On Wed, 21 Nov 2018, Robin Murphy wrote:

> On 21/11/2018 17:38, Christopher Lameter wrote:
> > On Wed, 21 Nov 2018, Will Deacon wrote:
> >
> > > > +#define ARM_V7S_TABLE_SLAB_CACHE SLAB_CACHE_DMA32
> >
> > SLAB_CACHE_DMA32??? WTH is going on here? We are trying to get rid of
> > the dma slab array.
>
> See the previous two patches in this series. If there's already a (better) way
> to have a kmem_cache which allocates its backing pages with GFP_DMA32, please
> do let us know.

Was not cced on the whole patchset. Trying to find it. Its best to
allocate DMA memory through the page based allocation functions.
dma_alloc_coherent() and friends.