From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52704) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cEKS3-0000WW-BM for qemu-devel@nongnu.org; Tue, 06 Dec 2016 13:26:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cEKRy-0003X4-A4 for qemu-devel@nongnu.org; Tue, 06 Dec 2016 13:26:51 -0500 Received: from hqemgate15.nvidia.com ([216.228.121.64]:9233) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cEKRy-0003WR-4y for qemu-devel@nongnu.org; Tue, 06 Dec 2016 13:26:46 -0500 From: Kirti Wankhede Date: Tue, 6 Dec 2016 23:58:12 +0530 Message-ID: <1481048892-29881-1-git-send-email-kwankhede@nvidia.com> In-Reply-To: <1481044425-23920-1-git-send-email-kwankhede@nvidia.com> References: <1481044425-23920-1-git-send-email-kwankhede@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain Subject: [Qemu-devel] [PATCH v2 2/2] vfio iommu: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: alex.williamson@redhat.com, pbonzini@redhat.com, kraxel@redhat.com, cjia@nvidia.com Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Kirti Wankhede Passing zero for the size to vfio_find_dma() isn't compatible with matching the start address of an existing vfio_dma. Doing so triggers a corner case. In vfio_find_dma(), when the start address is equal to dma->iova and size is 0, check for the end of search range makes it to take wrong side of RB-tree. That fails the search even though the address is present in mapped dma ranges. In functions pin_pages and unpin_pages, the iova which is being searched is base address of page to be pinned or unpinned. So here size should be set to PAGE_SIZE, as argument to vfio_find_dma(). Signed-off-by: Kirti Wankhede Signed-off-by: Neo Jia --- drivers/vfio/vfio_iommu_type1.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 8e9e94ccb2ff..023fba7b8d5a 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -581,7 +581,7 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data, struct vfio_pfn *vpfn; iova = user_pfn[i] << PAGE_SHIFT; - dma = vfio_find_dma(iommu, iova, 0); + dma = vfio_find_dma(iommu, iova, PAGE_SIZE); if (!dma) { ret = -EINVAL; goto pin_unwind; @@ -622,7 +622,7 @@ pin_unwind: dma_addr_t iova; iova = user_pfn[j] << PAGE_SHIFT; - dma = vfio_find_dma(iommu, iova, 0); + dma = vfio_find_dma(iommu, iova, PAGE_SIZE); vfio_unpin_page_external(dma, iova, do_accounting); phys_pfn[j] = 0; } @@ -659,7 +659,7 @@ static int vfio_iommu_type1_unpin_pages(void *iommu_data, dma_addr_t iova; iova = user_pfn[i] << PAGE_SHIFT; - dma = vfio_find_dma(iommu, iova, 0); + dma = vfio_find_dma(iommu, iova, PAGE_SIZE); if (!dma) goto unpin_exit; vfio_unpin_page_external(dma, iova, do_accounting); -- 2.7.0