From: Honggang LI Date: Wed, 15 Apr 2015 08:36:15 +0000 (+0800) Subject: mlx5: wrong page mask if CONFIG_ARCH_DMA_ADDR_T_64BIT enabled for 32Bit architectures X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=59d2d18cc4e9ba30b370db18d0e02d792699da96;p=deliverable%2Flinux.git mlx5: wrong page mask if CONFIG_ARCH_DMA_ADDR_T_64BIT enabled for 32Bit architectures 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 ----------------- Fixes: bf0bf77f6519 ('mlx5: Support communicating arbitrary host page size to firmware') Signed-off-by: Honggang Li Signed-off-by: Doug Ledford --- diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c index df2238372ea7..8a64542abc16 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) {