Re: [PATCH 1/4] vmalloc: lift the arm flag for coherent mappings to common code

[Russell King - ARM Linux admin]

On Fri, Aug 30, 2019 at 08:29:21AM +0200, Christoph Hellwig wrote:
> The arm architecture had a VM_ARM_DMA_CONSISTENT flag to mark DMA
> coherent remapping for a while.  Lift this flag to common code so
> that we can use it generically.  We also check it in the only place
> VM_USERMAP is directly check so that we can entirely replace that
> flag as well (although I'm not even sure why we'd want to allow
> remapping DMA appings, but I'd rather not change behavior).

Good, because if you did change that behaviour, you'd break almost
every ARM framebuffer and cripple ARM audio drivers.

-- 
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