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From:   Zhen Lei <thunder.leizhen@huawei.com>
To:     Robin Murphy <robin.murphy@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Rob Clark <robdclark@gmail.com>,
        Joerg Roedel <joro@8bytes.org>,
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        iommu <iommu@lists.linux-foundation.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
CC:     Zhen Lei <thunder.leizhen@huawei.com>,
        Hanjun Guo <guohanjun@huawei.com>,
        Libin <huawei.libin@huawei.com>,
        Guozhu Li <liguozhu@hisilicon.com>,
        "Xinwei Hu" <huxinwei@huawei.com>
Subject: [PATCH 4/7] iommu/amd: make sure TLB to be flushed before IOVA freed
Date:   Thu, 31 May 2018 15:42:46 +0800
Message-ID: <1527752569-18020-5-git-send-email-thunder.leizhen@huawei.com>
In-Reply-To: <1527752569-18020-1-git-send-email-thunder.leizhen@huawei.com>
References: <1527752569-18020-1-git-send-email-thunder.leizhen@huawei.com>
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Although the mapping has already been removed in the page table, it maybe
still exist in TLB. Suppose the freed IOVAs is reused by others before the
flush operation completed, the new user can not correctly access to its
meomory.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
---
 drivers/iommu/amd_iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 8fb8c73..93aa389 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2402,9 +2402,9 @@ static void __unmap_single(struct dma_ops_domain *dma_dom,
 	}
 
 	if (amd_iommu_unmap_flush) {
-		dma_ops_free_iova(dma_dom, dma_addr, pages);
 		domain_flush_tlb(&dma_dom->domain);
 		domain_flush_complete(&dma_dom->domain);
+		dma_ops_free_iova(dma_dom, dma_addr, pages);
 	} else {
 		pages = __roundup_pow_of_two(pages);
 		queue_iova(&dma_dom->iovad, dma_addr >> PAGE_SHIFT, pages, 0);
-- 
1.8.3