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From:   Christoph Hellwig <hch@lst.de>
To:     Thomas Hellstrom <thellstrom@vmware.com>
Cc:     =?UTF-8?q?Christian=20K=C3=B6nig?= <christian.koenig@amd.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        iommu@lists.linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH 2/2] dma-mapping: force unencryped devices are always addressing limited
Date:   Wed, 27 Nov 2019 15:40:06 +0100
Message-Id: <20191127144006.25998-3-hch@lst.de>
In-Reply-To: <20191127144006.25998-1-hch@lst.de>
References: <20191127144006.25998-1-hch@lst.de>
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Devices that are forced to DMA through unencrypted bounce buffers
need to be treated as if they are addressing limited.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 kernel/dma/mapping.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 1dbe6d725962..f6c35b53d996 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -416,6 +416,8 @@ EXPORT_SYMBOL_GPL(dma_get_merge_boundary);
  */
 bool dma_addressing_limited(struct device *dev)
 {
+	if (force_dma_unencrypted(dev))
+		return true;
 	return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
 			    dma_get_required_mask(dev);
 }
-- 
2.20.1