Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932634AbbDOFRi (ORCPT ); Wed, 15 Apr 2015 01:17:38 -0400 Received: from mail-wi0-f182.google.com ([209.85.212.182]:36147 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932260AbbDOFRa (ORCPT ); Wed, 15 Apr 2015 01:17:30 -0400 From: Eli Cohen X-Google-Original-From: Eli Cohen Date: Wed, 15 Apr 2015 08:17:26 +0300 To: Honggang Li Cc: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH linux-next v3] mlx5: wrong page mask if CONFIG_ARCH_DMA_ADDR_T_64BIT enabled for 32Bit architectures Message-ID: <20150415051726.GC27750@mtldesk30> References: <1429067957-9148-1-git-send-email-honli@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1429067957-9148-1-git-send-email-honli@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3457 Lines: 88 Acked-by: Eli Cohen On Wed, Apr 15, 2015 at 11:19:17AM +0800, Honggang Li wrote: > If CONFIG_ARCH_DMA_ADDR_T_64BIT enabled for x86 systems and physical > memory is more than 4GB, dma_map_page may return a valid memory > address which greater than 0xffffffff. As a result, the mlx5 device page > allocator RB tree will be initialized with valid addresses greater than > 0xfffffff. > > However, (addr & PAGE_MASK) set the high four bytes to zeros. So, it's > impossible for the function, free_4k, to release the pages whose > addresses greater than 4GB. Memory leaks. And mlx5_ib module can't > release the pages when user try to remove the module, as a result, > system hang. > > [root@rdma05 root]# dmesg | grep addr | head > addr = 3fe384000 > addr & PAGE_MASK = fe384000 > [root@rdma05 root]# rmmod mlx5_ib <---- hang on > > ---------------------- cosnole log ----------------- > mlx5_ib 0000:04:00.0: irq 138 for MSI/MSI-X > alloc irq_desc for 139 on node -1 > alloc kstat_irqs on node -1 > mlx5_ib 0000:04:00.0: irq 139 for MSI/MSI-X > 0000:04:00.0:free_4k:221:(pid 1519): page not found > 0000:04:00.0:free_4k:221:(pid 1519): page not found > 0000:04:00.0:free_4k:221:(pid 1519): page not found > 0000:04:00.0:free_4k:221:(pid 1519): page not found > ---------------------- cosnole log ----------------- > > Fix(bf0bf77 mlx5: Support communicating arbitrary host page size to > firmware) > > Signed-off-by: Honggang Li > --- > .../net/ethernet/mellanox/mlx5/core/pagealloc.c | 10 ++++++---- > 1 files changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c > index df22383..8a64542 100644 > --- a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c > +++ b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c > @@ -211,26 +211,28 @@ static int alloc_4k(struct mlx5_core_dev *dev, u64 *addr) > return 0; > } > > +#define MLX5_U64_4K_PAGE_MASK ((~(u64)0U) << PAGE_SHIFT) > + > static void free_4k(struct mlx5_core_dev *dev, u64 addr) > { > struct fw_page *fwp; > int n; > > - fwp = find_fw_page(dev, addr & PAGE_MASK); > + fwp = find_fw_page(dev, addr & MLX5_U64_4K_PAGE_MASK); > if (!fwp) { > mlx5_core_warn(dev, "page not found\n"); > return; > } > > - n = (addr & ~PAGE_MASK) >> MLX5_ADAPTER_PAGE_SHIFT; > + n = (addr & ~MLX5_U64_4K_PAGE_MASK) >> MLX5_ADAPTER_PAGE_SHIFT; > fwp->free_count++; > set_bit(n, &fwp->bitmask); > if (fwp->free_count == MLX5_NUM_4K_IN_PAGE) { > rb_erase(&fwp->rb_node, &dev->priv.page_root); > if (fwp->free_count != 1) > list_del(&fwp->list); > - dma_unmap_page(&dev->pdev->dev, addr & PAGE_MASK, PAGE_SIZE, > - DMA_BIDIRECTIONAL); > + dma_unmap_page(&dev->pdev->dev, addr & MLX5_U64_4K_PAGE_MASK, > + PAGE_SIZE, DMA_BIDIRECTIONAL); > __free_page(fwp->page); > kfree(fwp); > } else if (fwp->free_count == 1) { > -- > 1.7.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/