Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754183AbcLFRkn (ORCPT ); Tue, 6 Dec 2016 12:40:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58690 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751913AbcLFRkm (ORCPT ); Tue, 6 Dec 2016 12:40:42 -0500 Date: Tue, 6 Dec 2016 10:40:01 -0700 From: Alex Williamson To: Kirti Wankhede Cc: , , , , , Subject: Re: [PATCH v2 2/2] vfio iommu: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages Message-ID: <20161206104001.49390d41@t450s.home> 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; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 06 Dec 2016 17:40:02 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2084 Lines: 54 On Tue, 6 Dec 2016 22:43:45 +0530 Kirti Wankhede wrote: > vfio_dma keeps track of address range from (dma->iova + 0) to > (dma->iova + dma->size - 1), while vfio_find_dma() search logic looks for > range from (dma->iova + 1) to (dma->iova + dma->size). Also not true as described in reply to 1/2. > 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);