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Date:   Thu, 25 Jul 2019 07:11:44 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     "Andrew F. Davis" <afd@ti.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        John Stultz <john.stultz@linaro.org>,
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        Liam Mark <lmark@codeaurora.org>,
        Pratik Patel <pratikp@codeaurora.org>,
        Brian Starkey <Brian.Starkey@arm.com>,
        Vincent Donnefort <Vincent.Donnefort@arm.com>,
        Sudipto Paul <Sudipto.Paul@arm.com>,
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Subject: Re: [PATCH v6 4/5] dma-buf: heaps: Add CMA heap to dmabuf heaps
Message-ID: <20190725141144.GA14609@infradead.org>
References: <20190624194908.121273-1-john.stultz@linaro.org>
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On Thu, Jul 25, 2019 at 10:10:08AM -0400, Andrew F. Davis wrote:
> Pages yes, but not "normal" pages from the kernel managed area.
> page_to_pfn() will return bad values on the pages returned by this
> allocator and so will any of the kernel sync/map functions. Therefor
> those operations cannot be common and need special per-heap handling.

Well, that means this thing is buggy and abuses the scatterlist API
and we can't merge it anyway, so it is irrelevant.