From patchwork Mon Mar 9 18:18:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andre Przywara X-Patchwork-Id: 222811 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=unavailable 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 2ED9FC10F27 for ; Mon, 9 Mar 2020 18:20:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1721E208C3 for ; Mon, 9 Mar 2020 18:20:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727736AbgCISU3 (ORCPT ); Mon, 9 Mar 2020 14:20:29 -0400 Received: from foss.arm.com ([217.140.110.172]:55660 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727448AbgCISTI (ORCPT ); Mon, 9 Mar 2020 14:19:08 -0400 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 92D7411D4; Mon, 9 Mar 2020 11:19:07 -0700 (PDT) Received: from donnerap.arm.com (donnerap.cambridge.arm.com [10.1.197.25]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 44AC73F67D; Mon, 9 Mar 2020 11:19:06 -0700 (PDT) From: Andre Przywara To: "David S . Miller" , Radhey Shyam Pandey Cc: Michal Simek , Robert Hancock , netdev@vger.kernel.org, rmk+kernel@arm.linux.org.uk, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Andrew Lunn Subject: [PATCH v2 03/14] net: axienet: Propagate failure of DMA descriptor setup Date: Mon, 9 Mar 2020 18:18:40 +0000 Message-Id: <20200309181851.190164-4-andre.przywara@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200309181851.190164-1-andre.przywara@arm.com> References: <20200309181851.190164-1-andre.przywara@arm.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org When we fail allocating the DMA buffers in axienet_dma_bd_init(), we report this error, but carry on with initialisation nevertheless. This leads to a kernel panic when the driver later wants to send a packet, as it uses uninitialised data structures. Make the axienet_device_reset() routine return an error value, as it contains the DMA buffer initialisation. Make sure we propagate the error up the chain and eventually fail the driver initialisation, to avoid relying on non-initialised buffers. Signed-off-by: Andre Przywara Reviewed-by: Radhey Shyam Pandey --- .../net/ethernet/xilinx/xilinx_axienet_main.c | 26 ++++++++++++++----- 1 file changed, 19 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index 6ebfd19097d2..64f73533cabe 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -437,9 +437,10 @@ static void axienet_setoptions(struct net_device *ndev, u32 options) lp->options |= options; } -static void __axienet_device_reset(struct axienet_local *lp) +static int __axienet_device_reset(struct axienet_local *lp) { u32 timeout; + /* Reset Axi DMA. This would reset Axi Ethernet core as well. The reset * process of Axi DMA takes a while to complete as all pending * commands/transfers will be flushed or completed during this @@ -455,9 +456,11 @@ static void __axienet_device_reset(struct axienet_local *lp) if (--timeout == 0) { netdev_err(lp->ndev, "%s: DMA reset timeout!\n", __func__); - break; + return -ETIMEDOUT; } } + + return 0; } /** @@ -470,13 +473,17 @@ static void __axienet_device_reset(struct axienet_local *lp) * areconnected to Axi Ethernet reset lines, this in turn resets the Axi * Ethernet core. No separate hardware reset is done for the Axi Ethernet * core. + * Returns 0 on success or a negative error number otherwise. */ -static void axienet_device_reset(struct net_device *ndev) +static int axienet_device_reset(struct net_device *ndev) { u32 axienet_status; struct axienet_local *lp = netdev_priv(ndev); + int ret; - __axienet_device_reset(lp); + ret = __axienet_device_reset(lp); + if (ret) + return ret; lp->max_frm_size = XAE_MAX_VLAN_FRAME_SIZE; lp->options |= XAE_OPTION_VLAN; @@ -491,9 +498,11 @@ static void axienet_device_reset(struct net_device *ndev) lp->options |= XAE_OPTION_JUMBO; } - if (axienet_dma_bd_init(ndev)) { + ret = axienet_dma_bd_init(ndev); + if (ret) { netdev_err(ndev, "%s: descriptor allocation failed\n", __func__); + return ret; } axienet_status = axienet_ior(lp, XAE_RCW1_OFFSET); @@ -518,6 +527,8 @@ static void axienet_device_reset(struct net_device *ndev) axienet_setoptions(ndev, lp->options); netif_trans_update(ndev); + + return 0; } /** @@ -921,8 +932,9 @@ static int axienet_open(struct net_device *ndev) */ mutex_lock(&lp->mii_bus->mdio_lock); axienet_mdio_disable(lp); - axienet_device_reset(ndev); - ret = axienet_mdio_enable(lp); + ret = axienet_device_reset(ndev); + if (ret == 0) + ret = axienet_mdio_enable(lp); mutex_unlock(&lp->mii_bus->mdio_lock); if (ret < 0) return ret;