From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753589Ab2IQBRf (ORCPT ); Sun, 16 Sep 2012 21:17:35 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33645 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753502Ab2IQAuT (ORCPT ); Sun, 16 Sep 2012 20:50:19 -0400 Message-Id: <20120917003641.721250035@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 17 Sep 2012 01:38:17 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Santiago Leon , "David S. Miller" Subject: [ 112/135] ibmveth: Fix alignment of rx queue bug In-Reply-To: <20120917003625.784119135@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Santiago Leon commit d90c92fee89ccd75ef2646f3bde0b4c0450666c3 upstream. 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. Signed-off-by: Santiago Leon Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- 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 9010cea..b68d28a 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;