From d90c92fee89ccd75ef2646f3bde0b4c0450666c3 Mon Sep 17 00:00:00 2001 From: Santiago Leon Date: Tue, 4 Sep 2012 14:41:37 +0000 Subject: [PATCH] ibmveth: Fix alignment of rx queue bug This patch fixes a bug found by Nish Aravamudan (https://lkml.org/lkml/2012/5/15/220) where the driver is not following the spec (it is not aligning the rx buffer on a 16-byte boundary) and the hypervisor aborts the registration, making the device unusable. The fix follows BenH's recommendation (https://lkml.org/lkml/2012/7/20/461) to replace the kmalloc+map for a single call to dma_alloc_coherent() because that function always aligns to a 16-byte boundary. The stable trees will run into this bug whenever the rx buffer kmalloc call returns something not aligned on a 16-byte boundary. Cc: Signed-off-by: Santiago Leon Signed-off-by: David S. Miller --- drivers/net/ethernet/ibm/ibmveth.c | 26 +++++++++----------------- 1 file changed, 9 insertions(+), 17 deletions(-) diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c index 9010cea68bc3..b68d28a130e6 100644 --- a/drivers/net/ethernet/ibm/ibmveth.c +++ b/drivers/net/ethernet/ibm/ibmveth.c @@ -472,14 +472,9 @@ static void ibmveth_cleanup(struct ibmveth_adapter *adapter) } if (adapter->rx_queue.queue_addr != NULL) { - if (!dma_mapping_error(dev, adapter->rx_queue.queue_dma)) { - dma_unmap_single(dev, - adapter->rx_queue.queue_dma, - adapter->rx_queue.queue_len, - DMA_BIDIRECTIONAL); - adapter->rx_queue.queue_dma = DMA_ERROR_CODE; - } - kfree(adapter->rx_queue.queue_addr); + dma_free_coherent(dev, adapter->rx_queue.queue_len, + adapter->rx_queue.queue_addr, + adapter->rx_queue.queue_dma); adapter->rx_queue.queue_addr = NULL; } @@ -556,10 +551,13 @@ static int ibmveth_open(struct net_device *netdev) goto err_out; } + dev = &adapter->vdev->dev; + adapter->rx_queue.queue_len = sizeof(struct ibmveth_rx_q_entry) * rxq_entries; - adapter->rx_queue.queue_addr = kmalloc(adapter->rx_queue.queue_len, - GFP_KERNEL); + adapter->rx_queue.queue_addr = + dma_alloc_coherent(dev, adapter->rx_queue.queue_len, + &adapter->rx_queue.queue_dma, GFP_KERNEL); if (!adapter->rx_queue.queue_addr) { netdev_err(netdev, "unable to allocate rx queue pages\n"); @@ -567,19 +565,13 @@ static int ibmveth_open(struct net_device *netdev) goto err_out; } - dev = &adapter->vdev->dev; - adapter->buffer_list_dma = dma_map_single(dev, adapter->buffer_list_addr, 4096, DMA_BIDIRECTIONAL); adapter->filter_list_dma = dma_map_single(dev, adapter->filter_list_addr, 4096, DMA_BIDIRECTIONAL); - adapter->rx_queue.queue_dma = dma_map_single(dev, - adapter->rx_queue.queue_addr, - adapter->rx_queue.queue_len, DMA_BIDIRECTIONAL); if ((dma_mapping_error(dev, adapter->buffer_list_dma)) || - (dma_mapping_error(dev, adapter->filter_list_dma)) || - (dma_mapping_error(dev, adapter->rx_queue.queue_dma))) { + (dma_mapping_error(dev, adapter->filter_list_dma))) { netdev_err(netdev, "unable to map filter or buffer list " "pages\n"); rc = -ENOMEM; -- 2.30.2