From mboxrd@z Thu Jan 1 00:00:00 1970 From: robin.murphy@arm.com (Robin Murphy) Date: Thu, 31 May 2018 14:04:32 +0100 Subject: [PATCH 4/7] iommu/amd: make sure TLB to be flushed before IOVA freed In-Reply-To: <1527752569-18020-5-git-send-email-thunder.leizhen@huawei.com> References: <1527752569-18020-1-git-send-email-thunder.leizhen@huawei.com> <1527752569-18020-5-git-send-email-thunder.leizhen@huawei.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 31/05/18 08:42, Zhen Lei wrote: > 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. This change seems reasonable in isolation, but why is it right in the middle of a series which has nothing to do with x86? Robin. > Signed-off-by: Zhen Lei > --- > 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); >