Subject: Re: [PATCH] powerpc: ensure that swiotlb buffer is allocated from low memory

From: Michael Ellerman <[email-masked]>
Date: Wed, 18 Dec 2019 15:05:09 +1100 (AEDT)

On Wed, 2019-12-04 at 12:35:24 UTC, Mike Rapoport wrote:
> From: Mike Rapoport <[email-masked]>
> 
> Some powerpc platforms (e.g. 85xx) limit DMA-able memory way below 4G. If a
> system has more physical memory than this limit, the swiotlb buffer is not
> addressable because it is allocated from memblock using top-down mode.
> 
> Force memblock to bottom-up mode before calling swiotlb_init() to ensure
> that the swiotlb buffer is DMA-able.
> 
> Link: https://lkml.kernel.org/r/[email-masked]
> Reported-by: Christian Zigotzky <[email-masked]>
> Signed-off-by: Mike Rapoport <[email-masked]>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/8fabc623238e68b3ac63c0dd1657bf86c1fa33af

cheers