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Date: Fri, 2 May 2025 14:11:02 +0100
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Subject: Re: [PATCH v8 10/14] dma-contiguous: export
 dma_contiguous_default_area
To: Jens Wiklander <jens.wiklander@linaro.org>, linux-kernel@vger.kernel.org,
 linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org,
 linaro-mm-sig@lists.linaro.org, op-tee@lists.trustedfirmware.org,
 linux-arm-kernel@lists.infradead.org
Cc: Olivier Masse <olivier.masse@nxp.com>,
 Thierry Reding <thierry.reding@gmail.com>, Yong Wu <yong.wu@mediatek.com>,
 Sumit Semwal <sumit.semwal@linaro.org>,
 Benjamin Gaignard <benjamin.gaignard@collabora.com>,
 Brian Starkey <Brian.Starkey@arm.com>, John Stultz <jstultz@google.com>,
 "T . J . Mercier" <tjmercier@google.com>,
 =?UTF-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>,
 Sumit Garg <sumit.garg@kernel.org>, Matthias Brugger
 <matthias.bgg@gmail.com>,
 AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>,
 azarrabi@qti.qualcomm.com, Simona Vetter <simona.vetter@ffwll.ch>,
 Daniel Stone <daniel@fooishbar.org>,
 Rouven Czerwinski <rouven.czerwinski@linaro.org>,
 Marek Szyprowski <m.szyprowski@samsung.com>, iommu@lists.linux.dev
References: <20250502100049.1746335-1-jens.wiklander@linaro.org>
 <20250502100049.1746335-11-jens.wiklander@linaro.org>
From: Robin Murphy <robin.murphy@arm.com>
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In-Reply-To: <20250502100049.1746335-11-jens.wiklander@linaro.org>
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On 02/05/2025 10:59 am, Jens Wiklander wrote:
> Export the global variable dma_contiguous_default_area so
> dev_get_cma_area() can be called a module.

What dma_map_ops implementation is in a module? Without any other 
context, I can't help thinking this smells of something sketchy.

Thanks,
Robin.

> Cc: Marek Szyprowski <m.szyprowski@samsung.com>
> Cc: Robin Murphy <robin.murphy@arm.com>
> Cc: iommu@lists.linux.dev
> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> ---
>   kernel/dma/contiguous.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
> index 8df0dfaaca18..eb361794a9c5 100644
> --- a/kernel/dma/contiguous.c
> +++ b/kernel/dma/contiguous.c
> @@ -53,6 +53,7 @@
>   #endif
>   
>   struct cma *dma_contiguous_default_area;
> +EXPORT_SYMBOL(dma_contiguous_default_area);
>   
>   /*
>    * Default global CMA area size can be defined in kernel's .config.