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Date: Wed, 2 Aug 2023 11:47:25 +0200
From: Christoph Hellwig <hch@lst.de>
To: John Stultz <jstultz@google.com>
Cc: Christoph Hellwig <hch@lst.de>, Pintu Agarwal <pintu.ping@gmail.com>,
	Pintu Kumar <quic_pintu@quicinc.com>, linux-kernel@vger.kernel.org,
	akpm@linux-foundation.org, linux-mm@kvack.org,
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Subject: Re: [PATCH v2] dma-contiguous: define proper name for global cma
 region
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On Tue, Aug 01, 2023 at 10:39:04PM -0700, John Stultz wrote:
> So, forgive me, I've not had a chance to look into this, but my
> recollection was "reserved" is the name we see on x86, but other names
> are possibly provided via the dts node?

Indeed, dma_contiguous_default_area can also be set through
rmem_cma_setup, which then takes the name from DT.

> I believe on the hikey board its "linux,cma" is the name, so forcing
> it to reserved would break that.
> 
> Maybe instead add a compat config option to force the cma name (so x86
> can set it to "default" if needed)?


I think we'll just need to leave it as-is.  I with dma-heaps had never
exposed the name to userspace, but we'll have to lіve with it now.