From patchwork Thu Jan 25 11:14:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?WW9uZyBXdSAo5ZC05YuHKQ==?= X-Patchwork-Id: 10183913 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 60990601D5 for ; Thu, 25 Jan 2018 11:14:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 51E27289F5 for ; Thu, 25 Jan 2018 11:14:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 463CA28A0A; Thu, 25 Jan 2018 11:14:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 9ADF5289F5 for ; Thu, 25 Jan 2018 11:14:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=dVqC4ZP3EfK8DEYY1mHLr8+h5rFoJWUG0gO+gPt5LJ4=; b=eGspu6+eNxpEdo /+2l4GhXklBcHsvqre8+HbUc5jtkiiSATjpcyxPrNJJUz6Y1636SqfeM2euV63s1kQdV+KBofwiQq zM22fsQbVKZ1TBoHGFUXaoP/oWrcgeUfDK8pzNG2nR+BJzaGbdJUPWR3igVi3NcAc+xUVVwiB+jls +xyTjeT4S1Gh4auS+93vmBAZzFQrqM7B/LjYjT4Grg68C3UorQnkWrkPljnDtTk5+cElTA8Q7UTvD U0TuAt+HzjFVu4Zf6g9ceO/9iBPoaGNUIlyxvteG+Eob0JkGWdNlObJGrBJp+nPcIGzR1ztuopwjc RoILNI+RhNe/ea63Ogvw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1eefUN-0004ZT-33; Thu, 25 Jan 2018 11:14:39 +0000 Received: from [210.61.82.183] (helo=mailgw01.mediatek.com) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1eefUG-0004Rr-TA; Thu, 25 Jan 2018 11:14:35 +0000 X-UUID: 73a891e8c56247ec8fa49083b14c3af3-20180125 Received: from mtkcas06.mediatek.inc [(172.21.101.30)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 925717885; Thu, 25 Jan 2018 19:14:12 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs03n1.mediatek.inc (172.21.101.181) with Microsoft SMTP Server (TLS) id 15.0.1210.3; Thu, 25 Jan 2018 19:14:11 +0800 Received: from localhost.localdomain (10.17.3.153) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1210.3 via Frontend Transport; Thu, 25 Jan 2018 19:14:10 +0800 From: Yong Wu To: Joerg Roedel , Matthias Brugger , Robin Murphy Subject: [PATCH v3] iommu/mediatek: Move attach_device after iommu-group is ready for M4Uv1 Date: Thu, 25 Jan 2018 19:14:04 +0800 Message-ID: <1516878844-23021-1-git-send-email-yong.wu@mediatek.com> X-Mailer: git-send-email 1.8.1.1.dirty MIME-Version: 1.0 X-MTK: N X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: youlin.pei@mediatek.com, arnd@arndb.de, srv_heupstream@mediatek.com, Will Deacon , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Tomasz Figa , Alex Williamson , linux-mediatek@lists.infradead.org, Yong Wu , Bibby Hsieh , honghui.zhang@mediatek.com, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In the commit 05f80300dc8b, the iommu framework has supposed all the iommu drivers have their owner iommu-group, it get rid of the FIXME workarounds while the group is NULL. But the flow of Mediatek M4U gen1 looks a bit trick that it will hang at this case: ========================================== Unable to handle kernel NULL pointer dereference at virtual address 00000030 pgd = c0004000 [00000030] *pgd=00000000 PC is at mutex_lock+0x28/0x54 LR is at iommu_attach_device+0xa4/0xd4 pc : [] lr : [] psr: 60000013 sp : df0edbb8 ip : df0edbc8 fp : df0edbc4 r10: c114da14 r9 : df2a3e40 r8 : 00000003 r7 : df27a210 r6 : df2a90c4 r5 : 00000030 r4 : 00000000 r3 : df0f8000 r2 : fffff000 r1 : df29c610 r0 : 00000030 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none xxx (mutex_lock) from [] (iommu_attach_device+0xa4/0xd4) (iommu_attach_device) from [] (__arm_iommu_attach_device+0x28/0x90) (__arm_iommu_attach_device) from [] (arm_iommu_attach_device+0x1c/0x30) (arm_iommu_attach_device) from [] (mtk_iommu_add_device+0xfc/0x214) (mtk_iommu_add_device) from [] (add_iommu_group+0x3c/0x68) (add_iommu_group) from [] (bus_for_each_dev+0x78/0xac) (bus_for_each_dev) from [] (bus_set_iommu+0xb0/0xec) (bus_set_iommu) from [] (mtk_iommu_probe+0x328/0x368) (mtk_iommu_probe) from [] (platform_drv_probe+0x5c/0xc0) (platform_drv_probe) from [] (driver_probe_device+0x2f4/0x4d8) (driver_probe_device) from [] (__driver_attach+0x10c/0x128) (__driver_attach) from [] (bus_for_each_dev+0x78/0xac) (bus_for_each_dev) from [] (driver_attach+0x2c/0x30) (driver_attach) from [] (bus_add_driver+0x1e0/0x278) (bus_add_driver) from [] (driver_register+0x88/0x108) (driver_register) from [] (__platform_driver_register+0x50/0x58) (__platform_driver_register) from [] (m4u_init+0x24/0x28) (m4u_init) from [] (do_one_initcall+0xf0/0x17c) ========================= The root cause is that the device's iommu-group is NULL while arm_iommu_attach_device is called. This patch prepare a new iommu-group for the iommu consumer devices to fix this issue. CC: Robin Murphy CC: Honghui Zhang Fixes: 05f80300dc8b ('iommu: Finish making iommu_group support mandatory') Reported-by: Ryder Lee Signed-off-by: Yong Wu --- changes notes: v3: don't use the global variable and allocate a new iommu group before arm_iommu_attach_device following Robin's suggestion. v2: http://lists.infradead.org/pipermail/linux-mediatek/2018-January/011810.html Add mtk_domain_v1=NULL in domain_free for symmetry. v1: https://patchwork.kernel.org/patch/10176255/ --- drivers/iommu/mtk_iommu_v1.c | 49 ++++++++++++++++++++++---------------------- 1 file changed, 25 insertions(+), 24 deletions(-) diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index 542930c..aca76d2 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -418,20 +418,12 @@ static int mtk_iommu_create_mapping(struct device *dev, m4udev->archdata.iommu = mtk_mapping; } - ret = arm_iommu_attach_device(dev, mtk_mapping); - if (ret) - goto err_release_mapping; - return 0; - -err_release_mapping: - arm_iommu_release_mapping(mtk_mapping); - m4udev->archdata.iommu = NULL; - return ret; } static int mtk_iommu_add_device(struct device *dev) { + struct dma_iommu_mapping *mtk_mapping; struct of_phandle_args iommu_spec; struct of_phandle_iterator it; struct mtk_iommu_data *data; @@ -452,9 +444,30 @@ static int mtk_iommu_add_device(struct device *dev) if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops) return -ENODEV; /* Not a iommu client device */ + /* + * This is a short-term bodge because the ARM DMA code doesn't + * understand multi-device groups, but we have to call into it + * successfully (and not just rely on a normal IOMMU API attach + * here) in order to set the correct DMA API ops on @dev. + */ + group = iommu_group_alloc(); + if (IS_ERR(group)) + return PTR_ERR(group); + + err = iommu_group_add_device(group, dev); + iommu_group_put(group); + if (err) + return err; + data = dev->iommu_fwspec->iommu_priv; - iommu_device_link(&data->iommu, dev); + mtk_mapping = data->dev->archdata.iommu; + err = arm_iommu_attach_device(dev, mtk_mapping); + if (err) { + iommu_group_remove_device(dev); + return err; + } + iommu_device_link(&data->iommu, dev); group = iommu_group_get_for_dev(dev); if (IS_ERR(group)) return PTR_ERR(group); @@ -479,20 +492,8 @@ static void mtk_iommu_remove_device(struct device *dev) static struct iommu_group *mtk_iommu_device_group(struct device *dev) { - struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv; - - if (!data) - return ERR_PTR(-ENODEV); - - /* All the client devices are in the same m4u iommu-group */ - if (!data->m4u_group) { - data->m4u_group = iommu_group_alloc(); - if (IS_ERR(data->m4u_group)) - dev_err(dev, "Failed to allocate M4U IOMMU group\n"); - } else { - iommu_group_ref_get(data->m4u_group); - } - return data->m4u_group; + /* The iommu-group has always been allocated in add_device. */ + return NULL; } static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)