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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 3C24CC43603 for ; Thu, 19 Dec 2019 12:04:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 12BE7222C2 for ; Thu, 19 Dec 2019 12:04:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576757078; bh=3tpbtnl8OY57w2rdlJWwXlJgag79sYKXgNFcccIKSe4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=AGKNDoxOvKTd9ggt9tYs66jDrocPdR8+Ige2hnN/GfrsGjKTCxQDal8McOVMEcJaH 9d7A1SuAOYsFnbkHyxE3XTCBwV44JpkO0B3kBXcryDmO+2+/MdOgrFKAcUa/PCSFOe r5ZAHg7jKu9F8K+qYw0H9PezSqEbiWj+gaBUR4IU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727151AbfLSMEd (ORCPT ); Thu, 19 Dec 2019 07:04:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:36456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727106AbfLSMEa (ORCPT ); Thu, 19 Dec 2019 07:04:30 -0500 Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 576E7222C2; Thu, 19 Dec 2019 12:04:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576757069; bh=3tpbtnl8OY57w2rdlJWwXlJgag79sYKXgNFcccIKSe4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XL+3ciAAMACO2HKpFvxi0nRHLegR8Vt+TjRCNvBEv+grJOqV00RgTzinj0z6gAcrt qoQWFRj8DKrlJaVwOnl1Vjs3uyVPVL0Fu5GTgg+i+ScfWenIhTL98VixOPjWirl53d tsRxwCPrdQTnfACHG1eQHfjQ/7hRKyL3M4qfVqxY= From: Will Deacon To: linux-kernel@vger.kernel.org, iommu@lists.linuxfoundation.org Cc: kernel-team@android.com, Will Deacon , Jean-Philippe Brucker , Jordan Crouse , John Garry , Bjorn Helgaas , Saravana Kannan , Greg Kroah-Hartman , "Isaac J. Manjarres" , Robin Murphy , Lorenzo Pieralisi , Joerg Roedel , Ard Biesheuvel Subject: [PATCH v4 10/16] iommu/arm-smmu: Prevent forced unbinding of Arm SMMU drivers Date: Thu, 19 Dec 2019 12:03:46 +0000 Message-Id: <20191219120352.382-11-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191219120352.382-1-will@kernel.org> References: <20191219120352.382-1-will@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Forcefully unbinding the Arm SMMU drivers is a pretty dangerous operation, since it will likely lead to catastrophic failure for any DMA devices mastering through the SMMU being unbound. When the driver then attempts to "handle" the fatal faults, it's very easy to trip over dead data structures, leading to use-after-free. On John's machine, he reports that the machine was "unusable" due to loss of the storage controller following a forced unbind of the SMMUv3 driver: | # cd ./bus/platform/drivers/arm-smmu-v3 | # echo arm-smmu-v3.0.auto > unbind | hisi_sas_v2_hw HISI0162:01: CQE_AXI_W_ERR (0x800) found! | platform arm-smmu-v3.0.auto: CMD_SYNC timeout at 0x00000146 | [hwprod 0x00000146, hwcons 0x00000000] Prevent this forced unbinding of the drivers by setting "suppress_bind_attrs" to true. Link: https://lore.kernel.org/lkml/06dfd385-1af0-3106-4cc5-6a5b8e864759@huawei.com Reported-by: John Garry Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu-v3.c | 5 +++-- drivers/iommu/arm-smmu.c | 7 ++++--- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 68163b1d680d..9d4c9de6172d 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -3700,8 +3700,9 @@ MODULE_DEVICE_TABLE(of, arm_smmu_of_match); static struct platform_driver arm_smmu_driver = { .driver = { - .name = "arm-smmu-v3", - .of_match_table = of_match_ptr(arm_smmu_of_match), + .name = "arm-smmu-v3", + .of_match_table = of_match_ptr(arm_smmu_of_match), + .suppress_bind_attrs = true, }, .probe = arm_smmu_device_probe, .remove = arm_smmu_device_remove, diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 7c768f771001..5cbee88a3b83 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -2268,9 +2268,10 @@ static const struct dev_pm_ops arm_smmu_pm_ops = { static struct platform_driver arm_smmu_driver = { .driver = { - .name = "arm-smmu", - .of_match_table = of_match_ptr(arm_smmu_of_match), - .pm = &arm_smmu_pm_ops, + .name = "arm-smmu", + .of_match_table = of_match_ptr(arm_smmu_of_match), + .pm = &arm_smmu_pm_ops, + .suppress_bind_attrs = true, }, .probe = arm_smmu_device_probe, .remove = arm_smmu_device_remove, -- 2.24.1.735.g03f4e72817-goog 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=DKIM_INVALID,DKIM_SIGNED, 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 75186C43603 for ; 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Thu, 19 Dec 2019 12:04:29 +0000 (UTC) Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 576E7222C2; Thu, 19 Dec 2019 12:04:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576757069; bh=3tpbtnl8OY57w2rdlJWwXlJgag79sYKXgNFcccIKSe4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XL+3ciAAMACO2HKpFvxi0nRHLegR8Vt+TjRCNvBEv+grJOqV00RgTzinj0z6gAcrt qoQWFRj8DKrlJaVwOnl1Vjs3uyVPVL0Fu5GTgg+i+ScfWenIhTL98VixOPjWirl53d tsRxwCPrdQTnfACHG1eQHfjQ/7hRKyL3M4qfVqxY= From: Will Deacon To: linux-kernel@vger.kernel.org, iommu@lists.linuxfoundation.org Subject: [PATCH v4 10/16] iommu/arm-smmu: Prevent forced unbinding of Arm SMMU drivers Date: Thu, 19 Dec 2019 12:03:46 +0000 Message-Id: <20191219120352.382-11-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191219120352.382-1-will@kernel.org> References: <20191219120352.382-1-will@kernel.org> MIME-Version: 1.0 Cc: "Isaac J. Manjarres" , Jean-Philippe Brucker , Saravana Kannan , kernel-team@android.com, Robin Murphy , Greg Kroah-Hartman , Bjorn Helgaas , Will Deacon , Ard Biesheuvel X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Forcefully unbinding the Arm SMMU drivers is a pretty dangerous operation, since it will likely lead to catastrophic failure for any DMA devices mastering through the SMMU being unbound. When the driver then attempts to "handle" the fatal faults, it's very easy to trip over dead data structures, leading to use-after-free. On John's machine, he reports that the machine was "unusable" due to loss of the storage controller following a forced unbind of the SMMUv3 driver: | # cd ./bus/platform/drivers/arm-smmu-v3 | # echo arm-smmu-v3.0.auto > unbind | hisi_sas_v2_hw HISI0162:01: CQE_AXI_W_ERR (0x800) found! | platform arm-smmu-v3.0.auto: CMD_SYNC timeout at 0x00000146 | [hwprod 0x00000146, hwcons 0x00000000] Prevent this forced unbinding of the drivers by setting "suppress_bind_attrs" to true. Link: https://lore.kernel.org/lkml/06dfd385-1af0-3106-4cc5-6a5b8e864759@huawei.com Reported-by: John Garry Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu-v3.c | 5 +++-- drivers/iommu/arm-smmu.c | 7 ++++--- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 68163b1d680d..9d4c9de6172d 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -3700,8 +3700,9 @@ MODULE_DEVICE_TABLE(of, arm_smmu_of_match); static struct platform_driver arm_smmu_driver = { .driver = { - .name = "arm-smmu-v3", - .of_match_table = of_match_ptr(arm_smmu_of_match), + .name = "arm-smmu-v3", + .of_match_table = of_match_ptr(arm_smmu_of_match), + .suppress_bind_attrs = true, }, .probe = arm_smmu_device_probe, .remove = arm_smmu_device_remove, diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 7c768f771001..5cbee88a3b83 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -2268,9 +2268,10 @@ static const struct dev_pm_ops arm_smmu_pm_ops = { static struct platform_driver arm_smmu_driver = { .driver = { - .name = "arm-smmu", - .of_match_table = of_match_ptr(arm_smmu_of_match), - .pm = &arm_smmu_pm_ops, + .name = "arm-smmu", + .of_match_table = of_match_ptr(arm_smmu_of_match), + .pm = &arm_smmu_pm_ops, + .suppress_bind_attrs = true, }, .probe = arm_smmu_device_probe, .remove = arm_smmu_device_remove, -- 2.24.1.735.g03f4e72817-goog _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu