From patchwork Fri Nov 3 16:44:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Gunthorpe X-Patchwork-Id: 13444748 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 0BCACC4332F for ; Fri, 3 Nov 2023 16:45:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345684AbjKCQpc (ORCPT ); Fri, 3 Nov 2023 12:45:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345845AbjKCQp2 (ORCPT ); Fri, 3 Nov 2023 12:45:28 -0400 Received: from NAM04-DM6-obe.outbound.protection.outlook.com (mail-dm6nam04on2065.outbound.protection.outlook.com [40.107.102.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E151D4E; Fri, 3 Nov 2023 09:45:22 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=kRuBzS26uI2Ao5MX9ulmUBxHqayGRNXpBRhlrEAXE00WVvawHJeiq5D1G4kwb/Tp7B5vcbtS7nfCvV7LH1UzrEgSwPrWn3jt3voO6xiYsSe82wQ90lsoe7XOmBmLchTWM/FXr5PbQ1fQVu8diX3IlYLhobbXBqjQFEu6+d0NL7z2MARCuejYgv3YwzTvMzsseXG3alPLQcQxCtF4wGr25HTT3TghxakqdIzsBP9jhsHHgN5pJ3iwYf+avyuD2jMgqJGNGtWhX84tzCavN0x8vSSehCoibakJInLTDj/NuTLO0otWEJ5lVnPZ3mLGkyRskD7UrZFvy8oqGbhztWiCjw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=soH1zWNK7AVR4Z/sQmplqCYXMA35gKd2FYFGGTX9220=; b=RkTCLnCque40WFOeX2n6u/7y45dOHG0pR+IkVD3eGsOXUivl6f5wTxn26Uu23dbtYPyFHin0XED1AYqQVcS1fGwcttlfFvGixFovudHq2vCf1xH286Jw7MtuPJ1QkNItsrLngoW4Sk8MrVDE0CYrhcSP0zBwKNME+GHnvCr6AuGyAvI4LUK9GCOD8ZvrMWScjT0BR8ZmrKVNCAdnP774cvsGch4Mcc+T0Ya5LVyDMsmLdv4bvqkCRwL4Ky9zirba34jLc715QA7UfDzIVjCIEUo3fCwJQSdXFybhi7AHr1w+vocUyqmoM1ICACww9u+U/EUw2WfvUdFSFSpaMAQl7A== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=soH1zWNK7AVR4Z/sQmplqCYXMA35gKd2FYFGGTX9220=; b=brZ3lz4iEEHAqgnwC4/zE1B96CqntidirXbzQpfN8fCJE753DAovErkMR3L+WbhHrXAYjdKKysTgXkQu1QOreOgzBFEgC+Sl95Gg34GSX62oO3uDA6v2jMHJxsE0D0FGEPJB3Cu3/m2l+F4TYz8VpFPw5wrCylmij9JIzAdhrX/OPXiYh2KG3kUivmuDVGOPLDokrIWZ4uEL9nG2jJnfmdPwLnvFdD4ETO6DzV74bZNi4cxYiwu1KsVL3auV8Vqz2n80zNsOMHcM33lYl2VunMVYRP4zv4w29G5ddo5dA9f26ilX9UEZ8gza5NwEMSDFuuXDEr+imGX7URhWCci34Q== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from LV2PR12MB5869.namprd12.prod.outlook.com (2603:10b6:408:176::16) by PH0PR12MB7886.namprd12.prod.outlook.com (2603:10b6:510:26e::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6954.21; Fri, 3 Nov 2023 16:45:06 +0000 Received: from LV2PR12MB5869.namprd12.prod.outlook.com ([fe80::b53a:1092:9be2:cfb9]) by LV2PR12MB5869.namprd12.prod.outlook.com ([fe80::b53a:1092:9be2:cfb9%4]) with mapi id 15.20.6933.027; Fri, 3 Nov 2023 16:45:06 +0000 From: Jason Gunthorpe To: acpica-devel@lists.linuxfoundation.org, Alyssa Rosenzweig , Albert Ou , asahi@lists.linux.dev, Lu Baolu , Catalin Marinas , Dexuan Cui , devicetree@vger.kernel.org, David Woodhouse , Frank Rowand , Hanjun Guo , Haiyang Zhang , Christoph Hellwig , iommu@lists.linux.dev, Jean-Philippe Brucker , Jonathan Hunter , Joerg Roedel , "K. Y. Srinivasan" , Len Brown , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hyperv@vger.kernel.org, linux-mips@vger.kernel.org, linux-riscv@lists.infradead.org, linux-snps-arc@lists.infradead.org, linux-tegra@vger.kernel.org, Russell King , Lorenzo Pieralisi , Marek Szyprowski , Hector Martin , Palmer Dabbelt , Paul Walmsley , "Rafael J. Wysocki" , Robert Moore , Rob Herring , Robin Murphy , Sudeep Holla , Suravee Suthikulpanit , Sven Peter , Thierry Reding , Thomas Bogendoerfer , Krishna Reddy , Vineet Gupta , virtualization@lists.linux-foundation.org, Wei Liu , Will Deacon Cc: Zhenhua Huang Subject: [PATCH RFC 11/17] iommu: Hold iommu_probe_device_lock while calling ops->of_xlate Date: Fri, 3 Nov 2023 13:44:56 -0300 Message-ID: <11-v1-5f734af130a3+34f-iommu_fwspec_jgg@nvidia.com> In-Reply-To: <0-v1-5f734af130a3+34f-iommu_fwspec_jgg@nvidia.com> References: X-ClientProxiedBy: BL1PR13CA0329.namprd13.prod.outlook.com (2603:10b6:208:2c1::34) To LV2PR12MB5869.namprd12.prod.outlook.com (2603:10b6:408:176::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV2PR12MB5869:EE_|PH0PR12MB7886:EE_ X-MS-Office365-Filtering-Correlation-Id: 77f526dc-2203-4857-fab0-08dbdc8c3a9d X-LD-Processed: 43083d15-7273-40c1-b7db-39efd9ccc17a,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 77f526dc-2203-4857-fab0-08dbdc8c3a9d X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Nov 2023 16:45:04.2208 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: QbEszVzs+hprN+TANu3acvXks5HY+al0jaMNmCvSC+H1c+0tTPk2swn2RiUjqsbA X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB7886 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org This resolves the race around touching dev->iommu while generating the OF fwspec on the of_iommu_configure() flow: CPU0 CPU1 of_iommu_configure() iommu_device_register() .. bus_iommu_probe() iommu_fwspec_of_xlate() __iommu_probe_device() iommu_init_device() dev_iommu_get() .. ops->probe fails, no fwspec .. dev_iommu_free() dev->iommu->fwspec *crash* CPU1 is holding the iommu_probe_device_lock for iommu_init_device(), holding it around the of_xlate() and its related manipulation of dev->iommu will close it. The approach also closes a similar race for what should be a successful probe where the above basic construction results in ops->probe observing a partially initialized fwspec. Reported-by: Zhenhua Huang Closes: https://lore.kernel.org/linux-arm-kernel/20231017163337.GE282036@ziepe.ca/T/#mee0d7bdc375541934a571ae69f43b9660f8e7312 Signed-off-by: Jason Gunthorpe Reviewed-by: Jerry Snitselaar --- drivers/iommu/iommu.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 9cfba9d12d1400..62c82a28cd5db3 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -41,6 +41,7 @@ static struct kset *iommu_group_kset; static DEFINE_IDA(iommu_group_ida); static DEFINE_IDA(iommu_global_pasid_ida); +static DEFINE_MUTEX(iommu_probe_device_lock); static unsigned int iommu_def_domain_type __read_mostly; static bool iommu_dma_strict __read_mostly = IS_ENABLED(CONFIG_IOMMU_DEFAULT_DMA_STRICT); @@ -498,7 +499,6 @@ static int __iommu_probe_device(struct device *dev, struct iommu_fwspec *fwspec = caller_fwspec; const struct iommu_ops *ops; struct iommu_group *group; - static DEFINE_MUTEX(iommu_probe_device_lock); struct group_device *gdev; int ret; @@ -3002,8 +3002,11 @@ int iommu_fwspec_of_xlate(struct iommu_fwspec *fwspec, struct device *dev, if (!fwspec->ops->of_xlate) return -ENODEV; - if (!dev_iommu_get(dev)) + mutex_lock(&iommu_probe_device_lock); + if (!dev_iommu_get(dev)) { + mutex_unlock(&iommu_probe_device_lock); return -ENOMEM; + } /* * ops->of_xlate() requires the fwspec to be passed through dev->iommu, @@ -3015,6 +3018,7 @@ int iommu_fwspec_of_xlate(struct iommu_fwspec *fwspec, struct device *dev, ret = fwspec->ops->of_xlate(dev, iommu_spec); if (dev->iommu->fwspec == fwspec) dev->iommu->fwspec = NULL; + mutex_unlock(&iommu_probe_device_lock); return ret; } @@ -3044,6 +3048,8 @@ int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode, struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); int ret; + lockdep_assert_held(&iommu_probe_device_lock); + if (fwspec) return ops == fwspec->ops ? 0 : -EINVAL; @@ -3097,6 +3103,8 @@ int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + lockdep_assert_held(&iommu_probe_device_lock); + if (!fwspec) return -EINVAL; return iommu_fwspec_append_ids(fwspec, ids, num_ids);