From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD2E6C33CA2 for ; Fri, 10 Jan 2020 11:55:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB26520848 for ; Fri, 10 Jan 2020 11:55:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727928AbgAJLz2 (ORCPT ); Fri, 10 Jan 2020 06:55:28 -0500 Received: from foss.arm.com ([217.140.110.172]:43140 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728079AbgAJLyc (ORCPT ); Fri, 10 Jan 2020 06:54:32 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 648261435; Fri, 10 Jan 2020 03:54:31 -0800 (PST) Received: from donnerap.arm.com (donnerap.cambridge.arm.com [10.1.197.44]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 44ABC3F534; Fri, 10 Jan 2020 03:54:30 -0800 (PST) From: Andre Przywara To: "David S . Miller" , Radhey Shyam Pandey Cc: Michal Simek , Robert Hancock , netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 06/14] net: axienet: Check for DMA mapping errors Date: Fri, 10 Jan 2020 11:54:07 +0000 Message-Id: <20200110115415.75683-7-andre.przywara@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200110115415.75683-1-andre.przywara@arm.com> References: <20200110115415.75683-1-andre.przywara@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Especially with the default 32-bit DMA mask, DMA buffers are a limited resource, so their allocation can fail. So as the DMA API documentation requires, add error checking code after dma_map_single() calls to catch the case where we run out of "low" memory. Signed-off-by: Andre Przywara --- .../net/ethernet/xilinx/xilinx_axienet_main.c | 22 ++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index 82abe2b0f16a..8d2b67cbecf9 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -248,6 +248,11 @@ static int axienet_dma_bd_init(struct net_device *ndev) skb->data, lp->max_frm_size, DMA_FROM_DEVICE); + if (dma_mapping_error(ndev->dev.parent, lp->rx_bd_v[i].phys)) { + dev_kfree_skb(skb); + goto out; + } + lp->rx_bd_v[i].cntrl = lp->max_frm_size; } @@ -668,6 +673,7 @@ axienet_start_xmit(struct sk_buff *skb, struct net_device *ndev) dma_addr_t tail_p; struct axienet_local *lp = netdev_priv(ndev); struct axidma_bd *cur_p; + u32 orig_tail_ptr = lp->tx_bd_tail; num_frag = skb_shinfo(skb)->nr_frags; cur_p = &lp->tx_bd_v[lp->tx_bd_tail]; @@ -703,9 +709,11 @@ axienet_start_xmit(struct sk_buff *skb, struct net_device *ndev) cur_p->app0 |= 2; /* Tx Full Checksum Offload Enabled */ } - cur_p->cntrl = skb_headlen(skb) | XAXIDMA_BD_CTRL_TXSOF_MASK; cur_p->phys = dma_map_single(ndev->dev.parent, skb->data, skb_headlen(skb), DMA_TO_DEVICE); + if (dma_mapping_error(ndev->dev.parent, cur_p->phys)) + return NETDEV_TX_BUSY; + cur_p->cntrl = skb_headlen(skb) | XAXIDMA_BD_CTRL_TXSOF_MASK; for (ii = 0; ii < num_frag; ii++) { if (++lp->tx_bd_tail >= lp->tx_bd_num) @@ -716,6 +724,13 @@ axienet_start_xmit(struct sk_buff *skb, struct net_device *ndev) skb_frag_address(frag), skb_frag_size(frag), DMA_TO_DEVICE); + if (dma_mapping_error(ndev->dev.parent, cur_p->phys)) { + axienet_free_tx_chain(ndev, orig_tail_ptr, ii + 1, + NULL); + lp->tx_bd_tail = orig_tail_ptr; + + return NETDEV_TX_BUSY; + } cur_p->cntrl = skb_frag_size(frag); } @@ -796,6 +811,11 @@ static void axienet_recv(struct net_device *ndev) cur_p->phys = dma_map_single(ndev->dev.parent, new_skb->data, lp->max_frm_size, DMA_FROM_DEVICE); + if (dma_mapping_error(ndev->dev.parent, cur_p->phys)) { + dev_kfree_skb(new_skb); + return; + } + cur_p->cntrl = lp->max_frm_size; cur_p->status = 0; cur_p->skb = new_skb; -- 2.17.1