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Date: Tue, 7 May 2024 07:43:14 +0200
From: Christoph Hellwig <hch@lst.de>
To: "T.J. Mercier" <tjmercier@google.com>
Cc: Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Robin Murphy <robin.murphy@arm.com>, isaacmanjarres@google.com,
	Catalin Marinas <catalin.marinas@arm.com>, iommu@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] dma-direct: Set SG_DMA_SWIOTLB flag for dma-direct
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On Mon, May 06, 2024 at 09:39:53AM -0700, T.J. Mercier wrote:
> > You should not check, you simply must handle it by doing the proper
> > DMA API based ownership management.
> 
> That doesn't really work for uncached buffers.

What uncached buffers?