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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03DFAC433F5 for ; Fri, 4 Feb 2022 18:49:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 21E276B0072; Fri, 4 Feb 2022 13:49:16 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1CE986B0073; Fri, 4 Feb 2022 13:49:16 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 020936B0074; Fri, 4 Feb 2022 13:49:15 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0197.hostedemail.com [216.40.44.197]) by kanga.kvack.org (Postfix) with ESMTP id E64646B0072 for ; Fri, 4 Feb 2022 13:49:15 -0500 (EST) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id AB0BE18233655 for ; Fri, 4 Feb 2022 18:49:15 +0000 (UTC) X-FDA: 79105985070.20.3F593E1 Received: from NAM11-DM6-obe.outbound.protection.outlook.com (mail-dm6nam11on2085.outbound.protection.outlook.com [40.107.223.85]) by imf09.hostedemail.com (Postfix) with ESMTP id EEF6B140007 for ; Fri, 4 Feb 2022 18:49:14 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=SYLaxdOdFeHLNZJ8qSNHDgCh+5575F3l1BIfZ8hxKS3WPW3ui7cmdMtwtWRjSc3gZ5DWNsNQGWuXRuqcUaoH4hsgYYT5RY0HbPHe/JV4pxStgqJLLRzrT3HJT3T81499nViilUULDRTjos7XpLqb0i6/FF1w+jJeR8BTQmcI5nr0llgop9TnexbjAaGtM8FKFeFeHQGZOJ8Rx+ALWYPo0VLPF4AzF99lDRwaMsXqxg1YH8Zsn9PPlQLdS4lTwvb/Nc3la7Ckjv7LoJFsXAKILdrJ1voWHkm6Cxf/NL/wLy7YjrAUyBe0PY3Yc3fJsOp2GkgOdBmXvMXudiHlBzJ+IQ== 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=xKwMvn6/wg6wzPAL9NJjubP9y5cy/fiy4m9rEZcwLFU=; b=i7P4HQ1me3Tb2itZ09aSBHgnuaQ9ZEifsPr+NUhK+wdcU1TTY/SF/8zwkEsan6pdR5cZ8GZt4Q4dfNfNNnN03wCStsZLnKmZyTuFZaXwGOCkVOQgJCzVZO/w71XVAKe5xoNHxDKlgev0ZK0ttcc7O7QGD10qPbYxgX0d8WRzomKNWmSSgCNLYH2hsgySg9emvLwtEt1fVTYm+xOOKVU1rdDFBI5k+BGGBqNADspLdErdlIaAr+m7IEWzblRuqb+t7paz+xKsU2jysU3LeyPmYkEcsF/O2gNkyAvE+nTyCFuxgjmqgYdgs5PF0x41nxkJlE5hGqMKkxaXRnjD1Y4jKg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=none; dmarc=none; dkim=none; arc=none 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=xKwMvn6/wg6wzPAL9NJjubP9y5cy/fiy4m9rEZcwLFU=; b=b9KrBJRo5zD7aYxNVI3bEnzY1o3L2/luRkJz4n5umAtksm8c+qsWtwYTdNRzvyrb4sAXL92PSOhnM5dYdT1a+kdEzulDkZRl+DJ33gjD7V+1me5/lihuyGvLZVurDpRCbgWG6otaw86OqTIMXH43G2s33rqZQMvs8jkbAjkDFcs= Received: from BL1PR12MB5221.namprd12.prod.outlook.com (2603:10b6:208:30b::9) by BN7PR12MB2596.namprd12.prod.outlook.com (2603:10b6:408:29::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4951.12; Fri, 4 Feb 2022 18:49:12 +0000 Received: from BL1PR12MB5221.namprd12.prod.outlook.com ([fe80::b9af:8be3:36e5:1a13]) by BL1PR12MB5221.namprd12.prod.outlook.com ([fe80::b9af:8be3:36e5:1a13%7]) with mapi id 15.20.4951.017; Fri, 4 Feb 2022 18:49:11 +0000 Message-ID: Date: Fri, 4 Feb 2022 12:49:08 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Content-Language: en-US To: Borislav Petkov Cc: "Limonciello, Mario" , Martin Fernandez , linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-mm@kvack.org, tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, ardb@kernel.org, dvhart@infradead.org, andy@infradead.org, gregkh@linuxfoundation.org, rafael@kernel.org, rppt@kernel.org, akpm@linux-foundation.org, daniel.gutson@eclypsium.com, hughsient@gmail.com, alex.bazhaniuk@eclypsium.com, alison.schofield@intel.com, keescook@chromium.org References: <20220203164328.203629-1-martin.fernandez@eclypsium.com> <20220203164328.203629-7-martin.fernandez@eclypsium.com> <67d2711b-200c-0894-4ff7-beb3eb304399@amd.com> <5c5ffe29-d3d3-2955-cf78-ad275110f012@amd.com> <5ee34cad-8daf-6282-f2ed-cbc92a89d013@amd.com> From: Tom Lendacky Subject: Re: [PATCH v6 6/6] drivers/node: Show in sysfs node's crypto capabilities In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SN6PR01CA0001.prod.exchangelabs.com (2603:10b6:805:b6::14) To BL1PR12MB5221.namprd12.prod.outlook.com (2603:10b6:208:30b::9) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: f21543e2-7dfe-44e2-7aa9-08d9e80f0864 X-MS-TrafficTypeDiagnostic: BN7PR12MB2596:EE_ X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:8882; X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BL1PR12MB5221.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230001)(4636009)(366004)(31696002)(66574015)(86362001)(83380400001)(966005)(6486002)(53546011)(6666004)(186003)(38100700002)(36756003)(54906003)(31686004)(2616005)(6506007)(508600001)(6512007)(7416002)(5660300002)(2906002)(66556008)(66946007)(8676002)(8936002)(66476007)(316002)(26005)(4326008)(6916009)(45980500001)(43740500002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?L25hTVZucVpQa2tjOTJOakRKMU9YWWllTmlZd0twSFc3RHhjMkxnbnA2a1ln?= =?utf-8?B?dld5MFVrWnJQay9qM1h6UWpIV3l3L3JxSVNsWlRSQXlnemF2bDhNTDZVd0Nj?= =?utf-8?B?eklGbWIrSEo4VE14TUxiYmEwdWNHejNwS1Q4KzdlcmNZZXEvaUI4VTFtdEcv?= =?utf-8?B?QzVSb0hOQUVDSkZrbzhydndmRXIxZnFMa2hRSEdBYXlzLzdrSEExQmlDL0pX?= =?utf-8?B?N0N2b25sNXZPUEVyQlM5MmRhYjZNcFI0WHIrK2U3Q0RnaDlKUkpVOEpRVmlC?= =?utf-8?B?clNZZ2VXdURwSGpYam9NenZGMmQyam1KZHJ2OUhFbzZ6cFc4Sk1lS0VZM21N?= =?utf-8?B?MFI2cHVYT2hkcTFpOXVIOGlaMXo0Znluci81c1hIa3Zwb2FlRjNCSlc2ZHRW?= =?utf-8?B?enNhN3VneUg2NTJlR3VXeVkvZk5SOGhmeFA0V1U2ZWVpbjNFQ0NNYm1aOXJh?= =?utf-8?B?ZmlJM1lCaU90VmloQUtnL2FpUGJHK3RsbnQrSk03cnVNWGtyaWtVbVNMNFFo?= =?utf-8?B?cTV1VHhlM2JZUEJFVEorR3JONmVDSFlZUzBKQ1EzYnZMN2Z0MVJjRmlMVU1z?= =?utf-8?B?UEUvcFpIazNqQ2Q5enhXU2FONEwzY0dkNXJNRCtVQUt1RC8vU1dyUVZqWEFL?= =?utf-8?B?U0dMRXo4NVJ2QlNIdmhyRHJ5aCtPOWNsTDdTVjFUQ0NNYVVjbEpVamJKT2JW?= =?utf-8?B?elRpVHlOUUQzNFI3V3VTOW5jUkxXWU1iS24zSTlSU29Sb003dTdPSVBIZzFH?= =?utf-8?B?dFF3K0UwenkvOVoxRHhFRkJ3eHBVMWxsbGxCRXNJNmlmaVBMcXdKeHNSa3Ju?= =?utf-8?B?TndNMGV3cTIrR2NBdkV6S0MxbW9FcUJJVzN4dlZyOERCMUNMWHIxSFZMeWI1?= =?utf-8?B?eXdXamZaMThvMmkreE5jenJ0N0RXOUdEdFUzTm5kTVZ6N3ZkeDdWTnF2UzRk?= =?utf-8?B?MnVnaFJUbC84ZmM5ZldicytxRjY0SWRkd1JpZnErTEJuREV6dHdEbEw3VXBB?= =?utf-8?B?TU9PTDNDSG9TK21PSjlxTG0yaXh4VnFiUXJYUGJSdGtrR0txTlNTSTZvblJn?= =?utf-8?B?OHMyenQ4WEN0VXkvY3BlQnhnejF0cytxc2hvVGlTUExaZ2psakEvU3ZQcXhz?= =?utf-8?B?Y2NCcHV3SDlVSmlVOUM0a0NkTG5aRWVnNUdpUEJlcWJpZ1ByaU4wdTQ2RnRp?= =?utf-8?B?bFNmTjdoc0hsSUJiQXJLZUtDeTdpZmxvVDh2Uk04MzRqRjExQ1djVmszNk5z?= =?utf-8?B?Q0xDOEtUVDMxa0htZlZYRmJ2RWRPYkx3RWxSWmpkVzcwb2k1V1YwY1BIRG5R?= =?utf-8?B?QWVSNGdoU3JuRlVUQkFWY3JXd2VNZlBPUjd0Mllzbnd0K2dWNjB2UXphZ0RN?= =?utf-8?B?cmNZYVlQM1NmbXpMeW4rY1VaWDhIU3JTc0hCdXg5clhzaVJDODE3OUxhcjhx?= =?utf-8?B?TnFHako1REQvM3VDMmdCbEdJNmN3WU1pbXpIVEMwUjhya0VvMkJqMFV6cTV2?= =?utf-8?B?WUhxT2ZuTWRoUStybU5MaE1oQ0MwK0x5K3h5Y1FwaC8xVUJadjkxNk5ZMSsr?= =?utf-8?B?L3JJaUcyYVplT0ZCakRRVEdXbEhiTmpnNmhJUWNmdjV2RnBSdG5BSlRBekZt?= =?utf-8?B?OEJVWEFtSTFwZFhVd0t2bjhnN2ZoT0RHUkhZNkEwK2lkSFU3a1NuWWUzMUJo?= =?utf-8?B?TWsvTGdaT3lZdkxMZlBRTWVKb0lYS29uQ05sdHBmZ2lUMmVOMnVjUVR5NWZR?= =?utf-8?B?NVd6amlQZWNkTzUxYVpadEljbWRwdmdKYk9qQTZMRVVDUStWaUFqUUxGalcw?= =?utf-8?B?dlY2Ry8rREdCQlNadVhJcmw1WXlTL0c1TnhFQ0EvcTlidldkRklvZ2M5dU1Q?= =?utf-8?B?bENFN1BvWkUvb2Q3NnFpczBrQWxSTkJ3SWdZQ0QvcEx4RTV2bmxFS1lWd0dD?= =?utf-8?B?UXl4N0w0aVFQb0J0cFlyYnc2dzhQeElTUmJEQzFwTHhFVTJjQ0x4WXpxeno5?= =?utf-8?B?WWVCT1FlcFc4Y05RUnhXWWF5R201cWxQRTZ2ejJrMXh4cFdrMUFFV3ZuZWgv?= =?utf-8?B?RUZyUnVBRnd6Rjc1bnhzMVlrZy9yNVRSTmtPRXc3TlprRk5LWndCd2dhbmlJ?= =?utf-8?B?RFdzMUFEb29oVG83VUU5WUZmNFU2RWdEQldTYVp6Vzd1MkJ6bSt5SnUxN2pv?= =?utf-8?Q?CEyLTdDVrCqTM21F4KkAgcE=3D?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: f21543e2-7dfe-44e2-7aa9-08d9e80f0864 X-MS-Exchange-CrossTenant-AuthSource: BL1PR12MB5221.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Feb 2022 18:49:11.6497 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 3wFTqCgUoalYUAZhTH9T/0Yu+hAlJ8HAp5cpzJh3oOfmqAj1syWk9TKh8FIa8PJOtEQzqFmOfBsNRaPpXBZw1Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN7PR12MB2596 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: EEF6B140007 X-Rspam-User: nil Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=b9KrBJRo; dmarc=pass (policy=quarantine) header.from=amd.com; spf=pass (imf09.hostedemail.com: domain of Thomas.Lendacky@amd.com designates 40.107.223.85 as permitted sender) smtp.mailfrom=Thomas.Lendacky@amd.com X-Stat-Signature: taxihr4mp65gdrpf16tz1benwt7a6drt X-HE-Tag: 1644000554-239241 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2/4/22 12:00, Borislav Petkov wrote: > On Fri, Feb 04, 2022 at 11:12:04AM -0600, Tom Lendacky wrote: >> https://elixir.bootlin.com/linux/latest/source/arch/x86/kernel/process.c#L761 > > For those who won't open a browser just to see what he means :), that's > this snippet: > > void stop_this_cpu(void *dummy): > /* > * Use wbinvd on processors that support SME. This provides support > * for performing a successful kexec when going from SME inactive > * to SME active (or vice-versa). The cache must be cleared so that > * if there are entries with the same physical address, both with and > * without the encryption bit, they don't race each other when flushed > * and potentially end up with the wrong entry being committed to > * memory. > */ > if (boot_cpu_has(X86_FEATURE_SME)) > native_wbinvd(); > > > Well, we do clear our *representation* of CPUID flags for other features > - see output of > > $ git grep -E "(setup_)?clear_cpu_cap" > > for examples. We do that for SME even: early_detect_mem_encrypt(). > > Which means, since this needs to be "processors that support SME", this > line should change to: > > /* ... test the CPUID bit directly because the machine might've cleared > * X86_FEATURE_SME due to cmdline options. > */ > if (cpuid_eax(0x8000001f) & BIT(0)) > native_wbinvd(); > > I'd say... Yep, and that should be safe. We would have to look at the generated code as there can't be any memory stores after the native_wbinvd() and before the native_halt(). Thanks, Tom >