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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 58C37CA5FCE for ; Mon, 5 Oct 2026 06:41:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=871cQwQ7ACSQIz1Grs6A69/b+ccdbPv589rfmdbBVkY=; b=0q7FKFqsNLOEZF1BpyvqyvNBpr 86BrRbwTarAJOChuzD7u1j+zWLKFNha21vKhfdWB7JXH+ntNbmmQ3YTRsDdw742SxhEnDcaKJoI2z OWci6NVxgcmTF8z6n2Y+S6l4istWLRH7YwUx+nSL4oDSnMs/ckpuISIKQwa5SPeBjD9FjV094oCXX MPHFtx0RpgjAcooYHfaKD4/ZociPF0FnIJ0cPHa1VQ+f3FuSsHjSRsSQN8xwYK0+SKZnD6I+z1Qew kuVW1A4ReyIrLmya9gtsjymJxcKR7rNrM4v0Qjnt+C0bJE6C6Mzw23Nbm8hRyxXVjwZz32YHr6fru SFiMH/sA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xDcNr-0000000Fjtk-1hq6; Mon, 05 Oct 2026 06:41:11 +0000 Received: from mail-eastus2azlp170100001.outbound.protection.outlook.com ([2a01:111:f403:c110::1] helo=BN1PR04CU002.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xDcNp-0000000FjtD-2Sdm for kexec@lists.infradead.org; Mon, 05 Oct 2026 06:41:10 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=oW1QclmrvuGNdmbT+GUbdIzXxzqgBIy/uH+IoM2UJuHeh/yEi5B6MKp/csL4prQDm9wzD+TtrPa7UaaCmCgFJyYx7ok1BcotgDMYSVwW3sZRiu44+WLthkOkM2GQA6wZRPuvElY6ZSOYEj8Mcto46WBpI90owkk8ry0cz0m5C1C2oWrD4hB462bwOXR13C/du6s7x8zrd+6QRWhJsRoc+d9sGewGIgcABLyZBSJh0vK+m2+c+VTa1eaWKPN/lP8Ju9/A1wLkVVaB/obvIjMPVm8sMAxCaTUdkTiyyjbAe2v/Ds5mg5Fat46D6M8tNo57ujoarHvtCb1QW+1SkvOIHA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=871cQwQ7ACSQIz1Grs6A69/b+ccdbPv589rfmdbBVkY=; b=RXZDpNBMRncTOqlWkmWleX9aE2fYY68BNloDbgQDhRxZOrF6rGJSU7vaBg9ASzLsB/h9Ja74dYUysM9UqH8EYtvi7eMvi/ADdDPMnBrvtyIElITB2+wl+f4NFc53wjL4LUOJdNwHU2LVeflv/If3iHE/fgZyY236woLEjdJTHEbz6ZLuMiyAoJeqUqGm6STa6ojxqoariz33skBz6tjICNquoSBucJ06v7PloR9UPD0TEhX5Q3kIhiQAqsjnuZhRwuDGGp3xDsHnL/ji/rIKMc0O8w98OBFO6tvmsz3HH7erE7xKVcitPtKzeo7jLh3v+zT3neBiG2LbJg+WI8CWHQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=lists.linux.dev smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none (0) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=871cQwQ7ACSQIz1Grs6A69/b+ccdbPv589rfmdbBVkY=; b=ekD8JeAB11B01Vtg1iIZDCCj/4hL1mWvmFeLllZz/K1L1JN4S8X/0aCB8O6DrN4FkU/OQ3Cv5oIP4FVbz3kWYnwWeUpDEcLMDnnfeS0bErCaD6EgwzThJh2fzAZ+bpBmU0LMv9CcpsXs5o9Ycc858TC2P+IlQ/md8vgATQ5ksss= Received: from SJ0PR03CA0055.namprd03.prod.outlook.com (2603:10b6:a03:33e::30) by SA1PR12MB5640.namprd12.prod.outlook.com (2603:10b6:806:23e::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.472.15; Mon, 5 Oct 2026 06:41:02 +0000 Received: from CO1PEPF00012E5F.namprd05.prod.outlook.com (2603:10b6:a03:33e:cafe::5a) by SJ0PR03CA0055.outlook.office365.com (2603:10b6:a03:33e::30) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.21.472.20 via Frontend Transport; Mon, 5 Oct 2026 06:41:01 +0000 X-MS-Exchange-Authentication-Results: mx.microsoft.com 1; spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by CO1PEPF00012E5F.mail.protection.outlook.com (10.167.249.68) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.472.14 via Frontend Transport; Mon, 5 Oct 2026 06:41:01 +0000 Received: from BLRANKISONI.amd.com (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.49; Mon, 5 Oct 2026 01:40:52 -0500 From: Ankit Soni To: , , , CC: , , , , , , , , , , , , , , , , Subject: [RFC PATCH 1/7] iommu/amd: defer device attach only on a kdump boot Date: Mon, 5 Oct 2026 06:40:11 +0000 Message-ID: <20261005064018.1558-2-Ankit.Soni@amd.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20261005064018.1558-1-Ankit.Soni@amd.com> References: <20261005064018.1558-1-Ankit.Soni@amd.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: satlexmb07.amd.com (10.181.42.216) To satlexmb07.amd.com (10.181.42.216) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF00012E5F:EE_|SA1PR12MB5640:EE_ X-MS-Office365-Filtering-Correlation-Id: f4410f77-a2f0-4651-88a1-08df22ab9f02 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|82310400026|23010399003|36860700016|1800799024|11063799006|10067099003|56012099006|22082099003|18002099003|6133799003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(7416014)(376014)(82310400026)(23010399003)(36860700016)(1800799024)(11063799006)(10067099003)(56012099006)(22082099003)(18002099003)(6133799003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: f/UCWXWjk1K1h/ybvW5pV5Ei33mZ1uv4p0AG2Eex6w1WP575nvdEOg2mAyhWh3tR5V4QmUnDF0ZqgKHlORgwAdKk0DTK0GSiMIm4bEQy9ovUihbjgL0sYQtfOGX4OHBrFfhlGB0PtlkE0Q3dsLGbacAtYS0cy3TzzVPcB0hMR+yvs4IICVxiIx2yXgWG5d430NQkqXKz4R8uN952mmegNPOYS1SQfsjoEFYy9jla3c0A+NToVXExiTh2nMW1X7D7jtbf/04mW+CtR524jhYgIyUvlE4eDWUcRtMOCzVYLt8GoxHPv7vMepLTqzyopLxu7d+2q+6IBbuTNzk+S0VSpod+XR9RR34p/OBriqwGJLhatQQfHOqIfv/AC8G6VYUt2/z9JTcvgebJaGnS0JmuTqdyiBk+0icCpyMea+BPboLLvQ+Tvn5/vNSaYca0Baab X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Oct 2026 06:41:01.1580 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: f4410f77-a2f0-4651-88a1-08df22ab9f02 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF00012E5F.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB5640 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261004_234109_627858_014338D9 X-CRM114-Status: GOOD ( 12.88 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org find_dev_data() sets defer_attach whenever the IOMMU came up already translating. Only a kdump boot can ever complete such an attach: the core completes it from iommu_deferred_attach(), behind a static key that is enabled only when is_kdump_kernel(). That was harmless while a pre-enabled unit surviving driver init implied a kdump boot. A live-update handover breaks the implication, because a unit carrying preserved devices is deliberately left translating. The devices behind it that were not preserved had their DTEs blocked at shutdown, so the skipped attach never replaces the blocked entry and they come up unable to do DMA. Restrict the deferral to kdump, which is the only case that can complete it. Signed-off-by: Ankit Soni --- drivers/iommu/amd/iommu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 4dc306a4b5c6..a83ce4521f7f 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -500,7 +501,11 @@ static struct iommu_dev_data *find_dev_data(struct amd_iommu *iommu, u16 devid) if (!dev_data) return NULL; - if (translation_pre_enabled(iommu)) + /* + * Only a kdump boot can complete a deferred attach, so only a + * kdump boot may start one. + */ + if (translation_pre_enabled(iommu) && is_kdump_kernel()) dev_data->defer_attach = true; } -- 2.43.0