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Date: Tue, 27 Mar 2018 19:04:51 +0200 (CEST)
From: Sebastian Ott <sebott@linux.vnet.ibm.com>
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To: Christoph Hellwig <hch@lst.de>
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Subject: Re: dma_zalloc_coherent broken with
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On Tue, 27 Mar 2018, Christoph Hellwig wrote:
> On Tue, Mar 27, 2018 at 05:24:10PM +0200, Sebastian Ott wrote:
> > What do you mean by current implementations? Arch specific code? At least
> > on s390 we don't do that. dma-mapping.h doesn't do it either.
> 
> The arch implementations should do it.  Seems like s390 and potentially
> a few others don't.  I'm a little slow due to a cast on one arm, but I'll
> do an audit and will fix up anything I'll find.

What was wrong with the old behavior (let the caller decide - the same
as with memory allocations)? We have interfaces like dma_zalloc_coherent,
which explicitely set __GFP_ZERO. We have callers of dma_alloc followed by
a manually memset..

Sebastian