linux-kernel - [PATCH 5.15 378/667] dma-direct: dont call dma_set

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Message-Id: <20220607164946.086122133@linuxfoundation.org>
Date:   Tue,  7 Jun 2022 19:00:43 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Christoph Hellwig <hch@....de>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.15 378/667] dma-direct: dont call dma_set_decrypted for remapped allocations

From: Christoph Hellwig <hch@....de>

[ Upstream commit 5570449b6876f215d49ac4db9ccce6ff7aa1e20a ]

Remapped allocations handle the encrypted bit through the pgprot passed
to vmap, so there is no call dma_set_decrypted.  Note that this case is
currently entirely theoretical as no valid kernel configuration supports
remapped allocations and memory encryption currently.

Signed-off-by: Christoph Hellwig <hch@....de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 kernel/dma/direct.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index b9513fd68239..473964620773 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -241,8 +241,6 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 				__builtin_return_address(0));
 		if (!ret)
 			goto out_free_pages;
-		if (dma_set_decrypted(dev, ret, size))
-			goto out_free_pages;
 		memset(ret, 0, size);
 		goto done;
 	}
@@ -316,12 +314,13 @@ void dma_direct_free(struct device *dev, size_t size,
 	    dma_free_from_pool(dev, cpu_addr, PAGE_ALIGN(size)))
 		return;
 
-	dma_set_encrypted(dev, cpu_addr, 1 << page_order);
-
-	if (IS_ENABLED(CONFIG_DMA_REMAP) && is_vmalloc_addr(cpu_addr))
+	if (IS_ENABLED(CONFIG_DMA_REMAP) && is_vmalloc_addr(cpu_addr)) {
 		vunmap(cpu_addr);
-	else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
-		arch_dma_clear_uncached(cpu_addr, size);
+	} else {
+		if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
+			arch_dma_clear_uncached(cpu_addr, size);
+		dma_set_encrypted(dev, cpu_addr, 1 << page_order);
+	}
 
 	__dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
 }
-- 
2.35.1