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 66C60EB64DD for ; Mon, 7 Aug 2023 10:21:36 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A49B96B0075; Mon, 7 Aug 2023 06:21:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9FA1B8D0003; Mon, 7 Aug 2023 06:21:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 872AE8D0001; Mon, 7 Aug 2023 06:21:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 77BCA6B0075 for ; Mon, 7 Aug 2023 06:21:35 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 308A640329 for ; Mon, 7 Aug 2023 10:21:35 +0000 (UTC) X-FDA: 81096916950.16.C3DDD8B Received: from EUR03-DBA-obe.outbound.protection.outlook.com (mail-dbaeur03on2076.outbound.protection.outlook.com [40.107.104.76]) by imf06.hostedemail.com (Postfix) with ESMTP id 430D0180019 for ; Mon, 7 Aug 2023 10:21:30 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=armh.onmicrosoft.com header.s=selector2-armh-onmicrosoft-com header.b=oQyNepHl; dkim=pass header.d=armh.onmicrosoft.com header.s=selector2-armh-onmicrosoft-com header.b=oQyNepHl; spf=pass (imf06.hostedemail.com: domain of Szabolcs.Nagy@arm.com designates 40.107.104.76 as permitted sender) smtp.mailfrom=Szabolcs.Nagy@arm.com; dmarc=pass (policy=none) header.from=arm.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}") ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1691403691; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Mrs6y9Ptah9WPIEcrIb0ZeASDoxywYFtpPwtKfqhMWE=; b=u9N+4j9zQTbA0jee4MQKIKCkQKBXzHpxxddkZ+Ku2ABTtW8dH1w2oV+XmrFeiRwRUm94In l6OQZtdMjpJd+XH7dOpJE27Fyddkv2n20bnQ162Xqs1KOaixFF1aWQfjxyg0ZG3atjQlSC VK1mwQKR/WLCGqDNftO2HmigUwe4+hQ= ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1691403691; a=rsa-sha256; cv=fail; b=W/y/qz9HMKlBH8FnEtmpdPniX4Aid07GFhifpaD3vIVFZuFgAePQ2NWH3tRMg7s9/r5E4j ozGKQ/1vAPJ5Ywd6mbsK8nzmjtzJLBPUKaEp0vACU2I7gc6wfZsmAnfrsUv9lVCP0GVtLo UveqTlL8J3CGtk+/f/vpMHenAItPxbc= ARC-Authentication-Results: i=2; imf06.hostedemail.com; dkim=pass header.d=armh.onmicrosoft.com header.s=selector2-armh-onmicrosoft-com header.b=oQyNepHl; dkim=pass header.d=armh.onmicrosoft.com header.s=selector2-armh-onmicrosoft-com header.b=oQyNepHl; spf=pass (imf06.hostedemail.com: domain of Szabolcs.Nagy@arm.com designates 40.107.104.76 as permitted sender) smtp.mailfrom=Szabolcs.Nagy@arm.com; dmarc=pass (policy=none) header.from=arm.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}") DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector2-armh-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Mrs6y9Ptah9WPIEcrIb0ZeASDoxywYFtpPwtKfqhMWE=; b=oQyNepHlSzcZkHsVl1gWTKObuR6WipAgDDDyaUwJjBOR5TvLMEJzz0NHus7CsbcjMobDo62Wi1+X58GzYj/qVIek0EQKSgLSIQxi5D3pS8Gtl997RYuBnTyyNQ/dBPybVU/12SuNTphNaWHyc3/6RB34oJwKGVqb8K4TtEJDAU8= Received: from AS9PR06CA0023.eurprd06.prod.outlook.com (2603:10a6:20b:462::28) by DB5PR08MB10213.eurprd08.prod.outlook.com (2603:10a6:10:48d::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6652.21; Mon, 7 Aug 2023 10:21:27 +0000 Received: from AM7EUR03FT052.eop-EUR03.prod.protection.outlook.com (2603:10a6:20b:462:cafe::64) by AS9PR06CA0023.outlook.office365.com (2603:10a6:20b:462::28) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6652.26 via Frontend Transport; Mon, 7 Aug 2023 10:21:26 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 63.35.35.123) smtp.mailfrom=arm.com; dkim=pass (signature was verified) header.d=armh.onmicrosoft.com;dmarc=pass action=none header.from=arm.com; Received-SPF: Pass (protection.outlook.com: domain of arm.com designates 63.35.35.123 as permitted sender) receiver=protection.outlook.com; client-ip=63.35.35.123; helo=64aa7808-outbound-1.mta.getcheckrecipient.com; pr=C Received: from 64aa7808-outbound-1.mta.getcheckrecipient.com (63.35.35.123) by AM7EUR03FT052.mail.protection.outlook.com (100.127.140.214) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6678.15 via Frontend Transport; Mon, 7 Aug 2023 10:21:25 +0000 Received: ("Tessian outbound f9124736ff4f:v145"); Mon, 07 Aug 2023 10:21:25 +0000 X-CheckRecipientChecked: true X-CR-MTA-CID: d6abb263343ff9e9 X-CR-MTA-TID: 64aa7808 Received: from 7876b55f53d8.2 by 64aa7808-outbound-1.mta.getcheckrecipient.com id 9065A3D3-B4AC-44BB-8CEB-3887A004694F.1; Mon, 07 Aug 2023 10:21:15 +0000 Received: from EUR04-VI1-obe.outbound.protection.outlook.com by 64aa7808-outbound-1.mta.getcheckrecipient.com with ESMTPS id 7876b55f53d8.2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384); Mon, 07 Aug 2023 10:21:15 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=WDVtEsOp0ZspyDEtXDuyt2lDuf5M3rqll2Hidi63YbB2TTEh4Vb/wasdd4uwIuPYy2q//Zf5O2L8DksZmVVpaN3VYLpZ5y54Z6Z4tXVZWReNB3xqmVnj0WVmW5Pw0Ubd5/o8DM+V9k7DFXiucOx9FpiSJTvjakD7vWRpUAMKMwkuaKJXRJjuj6T9OzKHZKy4h47bRrmOaykvGUCcI36hDW7A9QnjAPzzNXvF26QG/J+JI1zoXaWVTnkO7mEaKN/4NX2E5JfewoF94wtTtiIGgm3YYZTtuYCDWTo1+Hb+xYdCGcFKNJYVRJt0ZF6leXny8pNevr0kVY6BWAKXbukVyg== 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=Mrs6y9Ptah9WPIEcrIb0ZeASDoxywYFtpPwtKfqhMWE=; b=cMABMlLUSQEgcDRC48dwh12XE/QqL/SgrUWPWlNMDnISJYswVit6whfTZo4umx96pGT1DLzJxydfn9MrgyqmtXjNIm38FSbcQ86VNuxYuLHO2cXumpMRTO9tsbeiRE7DVFiE0AwkpF79HAeLS+vY846I2qltkFbwiX+OK8DMdNsTYw2/VCfjGzOp2I9NuHaYI+kHClPUtqmwqax9dgeFXGXahuBCFtCqvGnlK2kYbZbSWnJmedvXcvRWCXLmUwbXBDs/F3B41JLf1Q58FZoMyJfT8pQTu7pMQPaoSwkIavJOD4Dzht3PMVWC+/F1LyifYl9c3Nd0aKluTzOsZuKphw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=arm.com; dmarc=pass action=none header.from=arm.com; dkim=pass header.d=arm.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector2-armh-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Mrs6y9Ptah9WPIEcrIb0ZeASDoxywYFtpPwtKfqhMWE=; b=oQyNepHlSzcZkHsVl1gWTKObuR6WipAgDDDyaUwJjBOR5TvLMEJzz0NHus7CsbcjMobDo62Wi1+X58GzYj/qVIek0EQKSgLSIQxi5D3pS8Gtl997RYuBnTyyNQ/dBPybVU/12SuNTphNaWHyc3/6RB34oJwKGVqb8K4TtEJDAU8= Authentication-Results-Original: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com; Received: from DB9PR08MB7179.eurprd08.prod.outlook.com (2603:10a6:10:2cc::19) by AS8PR08MB10151.eurprd08.prod.outlook.com (2603:10a6:20b:628::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6652.26; Mon, 7 Aug 2023 10:21:12 +0000 Received: from DB9PR08MB7179.eurprd08.prod.outlook.com ([fe80::adb0:61cb:8733:6db2]) by DB9PR08MB7179.eurprd08.prod.outlook.com ([fe80::adb0:61cb:8733:6db2%7]) with mapi id 15.20.6652.026; Mon, 7 Aug 2023 10:21:12 +0000 Date: Mon, 7 Aug 2023 11:20:58 +0100 From: Szabolcs Nagy To: Mark Brown , Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Kees Cook , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel Cc: "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v3 21/36] arm64/mm: Implement map_shadow_stack() Message-ID: References: <20230731-arm64-gcs-v3-0-cddf9f980d98@kernel.org> <20230731-arm64-gcs-v3-21-cddf9f980d98@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230731-arm64-gcs-v3-21-cddf9f980d98@kernel.org> X-ClientProxiedBy: LO6P123CA0017.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:313::7) To DB9PR08MB7179.eurprd08.prod.outlook.com (2603:10a6:10:2cc::19) MIME-Version: 1.0 X-MS-TrafficTypeDiagnostic: DB9PR08MB7179:EE_|AS8PR08MB10151:EE_|AM7EUR03FT052:EE_|DB5PR08MB10213:EE_ X-MS-Office365-Filtering-Correlation-Id: 2ff6d0a8-25b6-4cc0-977a-08db97300e76 x-checkrecipientrouted: true NoDisclaimer: true X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam-Untrusted: BCL:0; X-Microsoft-Antispam-Message-Info-Original: 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 X-Forefront-Antispam-Report-Untrusted: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DB9PR08MB7179.eurprd08.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230028)(4636009)(396003)(346002)(366004)(39860400002)(376002)(136003)(451199021)(1800799003)(186006)(6512007)(26005)(6506007)(36756003)(110136005)(54906003)(38100700002)(5660300002)(7416002)(86362001)(4744005)(4326008)(2906002)(66476007)(66556008)(66946007)(41300700001)(316002)(8936002)(8676002)(6666004)(478600001)(921005)(2616005)(6486002);DIR:OUT;SFP:1101; X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR08MB10151 Original-Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com; X-EOPAttributedMessage: 0 X-MS-Exchange-Transport-CrossTenantHeadersStripped: AM7EUR03FT052.eop-EUR03.prod.protection.outlook.com X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id-Prvs: fbe038b5-8ae4-4c9f-ce87-08db973005e5 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:63.35.35.123;CTRY:IE;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:64aa7808-outbound-1.mta.getcheckrecipient.com;PTR:ec2-63-35-35-123.eu-west-1.compute.amazonaws.com;CAT:NONE;SFS:(13230028)(4636009)(136003)(39850400004)(396003)(376002)(346002)(1800799003)(451199021)(186006)(82310400008)(46966006)(36840700001)(6512007)(6486002)(6666004)(6506007)(36860700001)(26005)(40480700001)(107886003)(336012)(2616005)(36756003)(81166007)(47076005)(86362001)(356005)(921005)(5660300002)(4744005)(41300700001)(8936002)(8676002)(4326008)(70586007)(2906002)(316002)(70206006)(82740400003)(110136005)(478600001)(54906003);DIR:OUT;SFP:1101; X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Aug 2023 10:21:25.9309 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 2ff6d0a8-25b6-4cc0-977a-08db97300e76 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: AM7EUR03FT052.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB5PR08MB10213 X-Rspamd-Queue-Id: 430D0180019 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 8rtbit8zn5apz6nsu5aefht1x7fha41s X-HE-Tag: 1691403690-199629 X-HE-Meta: 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 yRmob5ee 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 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: The 07/31/2023 14:43, Mark Brown wrote: > +SYSCALL_DEFINE3(map_shadow_stack, unsigned long, addr, unsigned long, size, unsigned int, flags) > +{ > + unsigned long alloc_size; > + unsigned long __user *cap_ptr; > + unsigned long cap_val; > + int ret; > + > + if (!system_supports_gcs()) > + return -EOPNOTSUPP; > + > + if (flags) > + return -EINVAL; > + > + if (addr % 16) > + return -EINVAL; mmap addr must be page aligned (and there is no align req on size). i'd expect similar api here. > + > + if (size == 16 || size % 16) > + return -EINVAL; why %16 and not %8 ?