[PATCH v2] mtd: onenand: omap2: Disable DMA for HIGHMEM buffers

Boris Brezillon boris.brezillon at bootlin.com
Fri Apr 20 13:01:34 PDT 2018

Hi Ladislav,

On Mon, 16 Apr 2018 08:52:59 +0200
Ladislav Michl <ladis at linux-mips.org> wrote:

> dma_map_single doesn't get the proper DMA address for vmalloced area,

That's not true, it returns the right DMA (physical) address, it's just

1/ the memory location is not necessarily physically contiguous
2/ in case your arch is VIVT ot VIPT, there may be several entries in
   the cache pointing to the same physical location, and the cache
   maintenance operations done by dma_map_single() will only operate on
   one of these entries.

> so disable DMA in this case.

The fix looks good though. Can you rephrase your commit message to make
it clearer.



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