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Date:   Mon, 28 Oct 2019 00:46:42 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     John Stultz <john.stultz@linaro.org>
Cc:     lkml <linux-kernel@vger.kernel.org>,
        Sandeep Patil <sspatil@google.com>,
        Laura Abbott <labbott@redhat.com>,
        Benjamin Gaignard <benjamin.gaignard@linaro.org>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        Liam Mark <lmark@codeaurora.org>,
        Pratik Patel <pratikp@codeaurora.org>,
        Brian Starkey <Brian.Starkey@arm.com>,
        "Andrew F . Davis" <afd@ti.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Yue Hu <huyue2@yulong.com>, Mike Rapoport <rppt@linux.ibm.com>,
        Chenbo Feng <fengc@google.com>,
        Alistair Strachan <astrachan@google.com>,
        Hridya Valsaraju <hridya@google.com>,
        dri-devel@lists.freedesktop.org
Subject: Re: [RFC][PATCH 1/2] mm: cma: Export cma symbols for cma heap as a
 module
Message-ID: <20191028074642.GB31867@infradead.org>
References: <20191025234834.28214-1-john.stultz@linaro.org>
 <20191025234834.28214-2-john.stultz@linaro.org>
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On Fri, Oct 25, 2019 at 11:48:33PM +0000, John Stultz wrote:
>  struct cma *dma_contiguous_default_area;
> +EXPORT_SYMBOL(dma_contiguous_default_area);

Please CC the dma maintainer.  And no, you have no business using this.

Even if you did, internals like this should always be EXPORT_SYMBOL_GPL.