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Date:   Tue, 20 Aug 2019 04:14:52 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Nicolin Chen <nicoleotsuka@gmail.com>
Cc:     Hillf Danton <hdanton@sina.com>,
        Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>,
        Christoph Hellwig <hch@lst.de>, kvalo@codeaurora.org,
        davem@davemloft.net, ath10k@lists.infradead.org,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, m.szyprowski@samsung.com,
        robin.murphy@arm.com, iommu@lists.linux-foundation.org,
        tobias.klausmann@freenet.de
Subject: Re: regression in ath10k dma allocation
Message-ID: <20190820021452.GA22792@lst.de>
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On Mon, Aug 19, 2019 at 06:58:52PM -0700, Nicolin Chen wrote:
> Right...the condition was in-between. However, not every caller
> of dma_alloc_contiguous() is supposed to have a coherent check.
> So we either add a 'bool coherent_ok' to the API or revert the
> dma-direct part back to the original. Probably former option is
> better?
> 
> Thank you for the debugging. I have been a bit distracted, may
> not be able to submit a fix very soon. Would you like to help?

Yeah, it turns out that while the idea for the dma_alloc_contiguous
helper was neat it didn't work out at all, and me pushing Nicolin
down that route was not a very smart idea.  Sorry for causing this
mess.

I think we'll just need to open code it for dma-direct for 5.3.
Hillf do you want to cook up a patch or should I do it?