From nobody Sun Sep 7 12:18:20 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D062EC38145 for ; Fri, 2 Sep 2022 12:33:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236288AbiIBMd1 (ORCPT ); Fri, 2 Sep 2022 08:33:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236594AbiIBMc3 (ORCPT ); Fri, 2 Sep 2022 08:32:29 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B9D7E2C48; Fri, 2 Sep 2022 05:27:20 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 5A714B82AA1; Fri, 2 Sep 2022 12:27:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1E0FC43142; Fri, 2 Sep 2022 12:27:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1662121638; bh=zFzdsXRNGhgpzL0zy6R6uex/IZJ/4hFDVtMV0UFxGGQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nkfge/YHGBiS88Od/englGEB8q01UjlCPro340LFXlSmKmwFn+ZvHaOZw3e0mL3IQ 9sEyVtLIQIPBvo9Iyd/N5L2CX9TKR92/RUW/Owjo8gfc+XFNiOEjQc9d6BjE9Zhkyo chV6EnLYXsQcCdAIoanSoGdh8b/6T7OMMHJida4g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sergei Antonov , Andrew Lunn , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.4 17/77] net: moxa: get rid of asymmetry in DMA mapping/unmapping Date: Fri, 2 Sep 2022 14:18:26 +0200 Message-Id: <20220902121404.221001880@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220902121403.569927325@linuxfoundation.org> References: <20220902121403.569927325@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Sergei Antonov [ Upstream commit 0ee7828dfc56e97d71e51e6374dc7b4eb2b6e081 ] Since priv->rx_mapping[i] is maped in moxart_mac_open(), we should unmap it from moxart_mac_stop(). Fixes 2 warnings. 1. During error unwinding in moxart_mac_probe(): "goto init_fail;", then moxart_mac_free_memory() calls dma_unmap_single() with priv->rx_mapping[i] pointers zeroed. WARNING: CPU: 0 PID: 1 at kernel/dma/debug.c:963 check_unmap+0x704/0x980 DMA-API: moxart-ethernet 92000000.mac: device driver tries to free DMA memo= ry it has not allocated [device address=3D0x0000000000000000] [size=3D1600 = bytes] CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0+ #60 Hardware name: Generic DT based system unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x34/0x44 dump_stack_lvl from __warn+0xbc/0x1f0 __warn from warn_slowpath_fmt+0x94/0xc8 warn_slowpath_fmt from check_unmap+0x704/0x980 check_unmap from debug_dma_unmap_page+0x8c/0x9c debug_dma_unmap_page from moxart_mac_free_memory+0x3c/0xa8 moxart_mac_free_memory from moxart_mac_probe+0x190/0x218 moxart_mac_probe from platform_probe+0x48/0x88 platform_probe from really_probe+0xc0/0x2e4 2. After commands: ip link set dev eth0 down ip link set dev eth0 up WARNING: CPU: 0 PID: 55 at kernel/dma/debug.c:570 add_dma_entry+0x204/0x2ec DMA-API: moxart-ethernet 92000000.mac: cacheline tracking EEXIST, overlappi= ng mappings aren't supported CPU: 0 PID: 55 Comm: ip Not tainted 5.19.0+ #57 Hardware name: Generic DT based system unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x34/0x44 dump_stack_lvl from __warn+0xbc/0x1f0 __warn from warn_slowpath_fmt+0x94/0xc8 warn_slowpath_fmt from add_dma_entry+0x204/0x2ec add_dma_entry from dma_map_page_attrs+0x110/0x328 dma_map_page_attrs from moxart_mac_open+0x134/0x320 moxart_mac_open from __dev_open+0x11c/0x1ec __dev_open from __dev_change_flags+0x194/0x22c __dev_change_flags from dev_change_flags+0x14/0x44 dev_change_flags from devinet_ioctl+0x6d4/0x93c devinet_ioctl from inet_ioctl+0x1ac/0x25c v1 -> v2: Extraneous change removed. Fixes: 6c821bd9edc9 ("net: Add MOXA ART SoCs ethernet driver") Signed-off-by: Sergei Antonov Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20220819110519.1230877-1-saproj@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/moxa/moxart_ether.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/moxa/moxart_ether.c b/drivers/net/etherne= t/moxa/moxart_ether.c index 383d72415c659..87327086ea8ca 100644 --- a/drivers/net/ethernet/moxa/moxart_ether.c +++ b/drivers/net/ethernet/moxa/moxart_ether.c @@ -74,11 +74,6 @@ static int moxart_set_mac_address(struct net_device *nde= v, void *addr) static void moxart_mac_free_memory(struct net_device *ndev) { struct moxart_mac_priv_t *priv =3D netdev_priv(ndev); - int i; - - for (i =3D 0; i < RX_DESC_NUM; i++) - dma_unmap_single(&priv->pdev->dev, priv->rx_mapping[i], - priv->rx_buf_size, DMA_FROM_DEVICE); =20 if (priv->tx_desc_base) dma_free_coherent(&priv->pdev->dev, @@ -193,6 +188,7 @@ static int moxart_mac_open(struct net_device *ndev) static int moxart_mac_stop(struct net_device *ndev) { struct moxart_mac_priv_t *priv =3D netdev_priv(ndev); + int i; =20 napi_disable(&priv->napi); =20 @@ -204,6 +200,11 @@ static int moxart_mac_stop(struct net_device *ndev) /* disable all functions */ writel(0, priv->base + REG_MAC_CTRL); =20 + /* unmap areas mapped in moxart_mac_setup_desc_ring() */ + for (i =3D 0; i < RX_DESC_NUM; i++) + dma_unmap_single(&priv->pdev->dev, priv->rx_mapping[i], + priv->rx_buf_size, DMA_FROM_DEVICE); + return 0; } =20 --=20 2.35.1