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 6BDCED2068A for ; Wed, 16 Oct 2024 00:50:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D6F776B007B; Tue, 15 Oct 2024 20:50:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D1F686B0082; Tue, 15 Oct 2024 20:50:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B720E6B0083; Tue, 15 Oct 2024 20:50:27 -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 9440D6B007B for ; Tue, 15 Oct 2024 20:50:27 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id BE96D12190F for ; Wed, 16 Oct 2024 00:50:18 +0000 (UTC) X-FDA: 82677634116.09.243D9AE Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf22.hostedemail.com (Postfix) with ESMTP id 49EA0C0009 for ; Wed, 16 Oct 2024 00:50:14 +0000 (UTC) Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2023-11-20 header.b=WBuOvN7l; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=vqfLhMwa; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf22.hostedemail.com: domain of anthony.yznaga@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=anthony.yznaga@oracle.com; dmarc=pass (policy=reject) header.from=oracle.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1729039681; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=1ZZavvmL+POZ3yS4tlJRbY2KfmsSnJ2i1ab4gpW8W5w=; b=ZkJjYQw6HvdNs6u/OM4LXfI8kjditZJoWJ2oSlGsa+MH9sUjDiPoEZaeWX+tc0mDFcvipd qzKh2+vqUanCGZbueHWi3CQ44Q0gHuN7RBHWoSqstyfzVer3/elUKnL2EV3bs/Ky5J1F0Q otea7djxA1kTw6M3DJ3vXCXBwr9zasw= ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1729039681; a=rsa-sha256; cv=pass; b=O5jcTPChrr/Jcv4/zodjwBA/4GwkahamKf6dutQmDI/aaNRM6Vglgyv1bzt3XPrFkFyhf+ fncsy/gpcFFnHg3FA9aHE4PMjuO7k9cgYVtCbIMRAQ6XzyKGs1vRXSAsrPOe4kvUIdCNEK yp5YqVRXMNHyNJgVWAwzcAIgWcudQvs= ARC-Authentication-Results: i=2; imf22.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2023-11-20 header.b=WBuOvN7l; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=vqfLhMwa; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf22.hostedemail.com: domain of anthony.yznaga@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=anthony.yznaga@oracle.com; dmarc=pass (policy=reject) header.from=oracle.com Received: from pps.filterd (m0246627.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49FHthEU019373; Wed, 16 Oct 2024 00:50:04 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s= corp-2023-11-20; bh=1ZZavvmL+POZ3yS4tlJRbY2KfmsSnJ2i1ab4gpW8W5w=; b= WBuOvN7lX/pOm2mEWM9pAvY5uPf4pFux1welOqY90YECn1tTGmx+QN5SmNSpk2d6 uyQe4lXNSYQUIEv920OGW3JbCVeYQjFQ/hektGOCqaXMqqDmiLwAdqLojpmaws5Q suAqh3VzDf2sCJV4ZGJHAxSVp9laG9Y+NPYZHUET4DNudZRN2hlwKsf+iexyBohU VLRW8I/24F7PTkD3bOCEDxg/jEws6lJ/k69FhwRkaN0tY8CnzdOmED0lcnmgmmo4 oxa8BQ7mSefP+kLy+igQCWCcsuR4yrinmDzM0Gijzq+jAWYlLUYCmMbzZ8LXyWY5 2xoICHczD3MH9GqeOHj6Ig== Received: from phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta02.appoci.oracle.com [147.154.114.232]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 427gq7jk7u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 16 Oct 2024 00:50:03 +0000 (GMT) Received: from pps.filterd (phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 49FM6kvL019943; Wed, 16 Oct 2024 00:50:02 GMT Received: from nam12-mw2-obe.outbound.protection.outlook.com (mail-mw2nam12lp2048.outbound.protection.outlook.com [104.47.66.48]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 427fj86bta-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 16 Oct 2024 00:50:02 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=eo5v+3gVtPsQGs9x7JhXQ156gQTU83YQCGnp978zWauvQoStXbqssobsRcefosczscs4/zB2zmFkpx9gNK3ll6SRWkRa9oRXvbhu11K1fIyY1nz+6Gzk5TCzMBJ9ByqocWGTm0D3xY2LidqeLFfHreuA+apMM/BzOx9da4OmveJ96j0gA6Cph6Wcsa4vUCExmjBP8Lcw3mVz0IfkoKb+vLhYXdOzbLbJ3/Fsa7X0NqfA/q4LCbTiodmJ07glg/onHfF4tCg4sT4Mw/nIdQ/PKwlab2NoVCatVm3IATjgA4gqvagoy7iwrlIuewCyTTSGz7kX6rMkfXuQks17RHa1QA== 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=1ZZavvmL+POZ3yS4tlJRbY2KfmsSnJ2i1ab4gpW8W5w=; b=aK480X2b3U0oAzhg9aTEWVcM4RuwoOnRa4vVms+LVzaneo9vuZcaLQpeuGQ6znWiq1cDJHD2fyF0nWkjJwR1asrGKieLsVvkPy3z1+FEcK9Ls6pxLIzzdATESZ4bILAbrT1GrECClk9Od/Gd7JO8cr9Uw3ceH2VXpQ8QUwtfDvpxskBUK/G6IlTAh/rnhY0Ngj14KjueQo/so9zXPLqJn01y/8a4ZZOgnBOl+z/S85TdeyVhMOeJ9ID0vj/BxBE8QoeY1lxvPaXnjIstqjO+yw5H56xdX0JL1nquoJu/3iUhzunkbSQRQkoc/LeYL6GWsX7xgZdQMneZRN4RWgK9eQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=1ZZavvmL+POZ3yS4tlJRbY2KfmsSnJ2i1ab4gpW8W5w=; b=vqfLhMwaKx5eYVRnWXJY83dVmXIEFAnrJcOuhvQ5cfg5Got8/5usTz/90Snt1Ed+ZbsILxBOEW5ARwEDRnQsqJDAwc7DFCouWJB6EiEp8iHyQIchRZnJSMBTidZLEXVsvCjH8uFDX0MIJGZuEqBW+Uq+WxNq3jzrbmwCLt5EbYc= Received: from MW6PR10MB7660.namprd10.prod.outlook.com (2603:10b6:303:24b::12) by PH7PR10MB6132.namprd10.prod.outlook.com (2603:10b6:510:1f4::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8069.17; Wed, 16 Oct 2024 00:49:57 +0000 Received: from MW6PR10MB7660.namprd10.prod.outlook.com ([fe80::41fa:92d3:28b9:2a15]) by MW6PR10MB7660.namprd10.prod.outlook.com ([fe80::41fa:92d3:28b9:2a15%7]) with mapi id 15.20.8048.020; Wed, 16 Oct 2024 00:49:57 +0000 Message-ID: <345a8c5e-1f7d-4d73-a3a0-7d0040e5d5a6@oracle.com> Date: Tue, 15 Oct 2024 17:49:53 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH v3 05/10] mm/mshare: Add ioctl support To: Jann Horn Cc: akpm@linux-foundation.org, willy@infradead.org, markhemm@googlemail.com, viro@zeniv.linux.org.uk, david@redhat.com, khalid@kernel.org, andreyknvl@gmail.com, dave.hansen@intel.com, luto@kernel.org, brauner@kernel.org, arnd@arndb.de, ebiederm@xmission.com, catalin.marinas@arm.com, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhiramat@kernel.org, rostedt@goodmis.org, vasily.averin@linux.dev, xhao@linux.alibaba.com, pcc@google.com, neilb@suse.de, maz@kernel.org References: <20240903232241.43995-1-anthony.yznaga@oracle.com> <20240903232241.43995-6-anthony.yznaga@oracle.com> Content-Language: en-US From: Anthony Yznaga In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: SJ0PR03CA0248.namprd03.prod.outlook.com (2603:10b6:a03:3a0::13) To MW6PR10MB7660.namprd10.prod.outlook.com (2603:10b6:303:24b::12) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MW6PR10MB7660:EE_|PH7PR10MB6132:EE_ X-MS-Office365-Filtering-Correlation-Id: 1e5ca66e-bf8c-44a1-f769-08dced7c74cc X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|366016|1800799024; X-Microsoft-Antispam-Message-Info: =?utf-8?B?aUhuV1JLdzVQaHB2aVpJRWpEYUw0a3BlbXZsYlN5VkxLdjI5bGRnRXdYTDF5?= =?utf-8?B?bW9JWkNYVVZCc1ZpaWRMbzJQaVpWTHRpN0xQOS84eTQzdzVNc01ZVE12T2g4?= =?utf-8?B?WkF1Wm9aV3JjVmNGeXNONk05SjZTclZ4ZmY5OXRiempKY1d5bGxWdElZUDhV?= =?utf-8?B?bVd4VGlYWDFTdmcyS1N4RjVIK1FQWWU3ZnFlTXo0QnNNV3hROXd0ZytoWHc1?= =?utf-8?B?azdlRHNWTGZOWnUwZm1iOFpVQ0JFTktESkRZYTU0cjB6bW1PeG10dzVTM1Vx?= =?utf-8?B?NG1RZ1AxM1BiUU1weGNtUzM2U3JyM0FDU1g5NTkyUS8wYkpwWjZ2Myt2QzN1?= =?utf-8?B?d1BUQ0lvWE05ZFRqNmFOeDBSRm9ucEhxR0RpR0JQNFN2T0YvRmNxUS9Tc2o5?= =?utf-8?B?djd1Z3lud0RTeVRaMkJMNm9nTEFuQk00NzJCWFlkV1M2eEtoWVhBYnFtbjdy?= =?utf-8?B?MmZyaEQwUjE0YVJZN0QwVEkvUU8zN2EwaE1WSWdza1RmZHRpUS9Fc09ZZGR6?= =?utf-8?B?SzhHVDZOdTV4Smp5eDc5aEZUQ3JtU2g2RGdoam0vdVRkK3pYWGEyNVJIamNU?= =?utf-8?B?Y0FCRjFwVVgwRDQ2MFo2UWFqNzJlZ01MYzVRaHRtR1pQYi9UODF2U0hNZCtz?= =?utf-8?B?TTdzMGtsY3dZMDRnMXhPRXRpNzlJSnViQytTUTQxOTNCaCtKdjRpSExWWWUw?= =?utf-8?B?cWk1RHM1bHlGUTFtN0NpMDU5TDFwZXl2ZU9pOFhuQUh2cjl4Szc1UnF3T01s?= =?utf-8?B?Q1hncEJUUDNZK1QyLytNeDZVcExLTjE4cGNqZzRGNGxvVFI0UjcrejB2M3VJ?= =?utf-8?B?LytOaGpLR0M3M2tkdHpsbnl3WmdoQ1U0ak11VEl6UGhwN3cyWndxNVpIN0NE?= =?utf-8?B?K1J4U0M2TnVKRHRLNHB2d2tQK1h2dnhrbXFOZzM4SHFxeHdMZzNPUkR2UHZl?= =?utf-8?B?ZnBuQ3N3UHE5bTB5Z3UrdkFxNFJNbDUrcTZwc3ZEeS9YVTlLM0NRemFSRk1y?= =?utf-8?B?eGIwL1VZOXVtWHFSTndzWjFmbytMWjdXaDFaN0g2eGY0ZFM5cUtCYlUwNjhj?= =?utf-8?B?N3VsWURzUmFhRnhuMitxWWVKMDA0UHoxVEVvSTc1WUFuY0x0LzVBZTlrek82?= =?utf-8?B?Y29sdXpwTkxpRVgwdDJpREhKL1JYaDNKdDIyV1pXVkpwL082NlZob1crZERl?= =?utf-8?B?U2VPaHV3aFgzYmFvMEhxdGdXcTJSOVFvZ0xnTGhhREkwMzYyN3FOMjJWRFRh?= =?utf-8?B?M3ZYNVNiTmhuM2NQQjNXYVFaMldyTG1qNWlWNWU3cHI5Zzk1OGt5dVlEWU1X?= =?utf-8?B?WGhmaDlTemVPMGpsRzdETkN2U0RoUThXTUFodkNnMTNpS1dhZDRWK0t3eWZH?= =?utf-8?B?cjZUbjNsZjFaWE1VS2M0M0J0WGpnOFcydXNTL3FJckNqd3hQUGNFU0ZJSkhh?= =?utf-8?B?anI0c3BLaVNkcTdUSjFoUjZqU0U1QVhFNktaTE1sNzd6OFRnTnpKN3dNdE5j?= =?utf-8?B?RDcxMU9KSk50VGdJZTRlTlIxSEpwd0FQVnczQ3FYRWJnenJBUjliTmMvN2lV?= =?utf-8?B?NERyVjRMZk9OVlBKb1ErL090QVVxNWhqQzVka1dwSEpPUERVSjk1V3RjeVNK?= =?utf-8?B?T3VFWFBVZlcwQVFKZ3pSMENybi8xNzNrVkFnSllEZml4Q2NIYWNNVVh4ejdh?= =?utf-8?B?WFZwOE9NbFgxZnh2N1kxQkhtQUtJQ2J6WlpVS1BOOW9LeFBoeEFMWDFBPT0=?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:MW6PR10MB7660.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(7416014)(376014)(366016)(1800799024);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?RHFxSEpibVEvTFdTSXVxcTJTQVdsUXhhbDE2ZEt1MSt1eFg5UHhFN1FjTVhE?= =?utf-8?B?TTh1UDJVQlF6Tk80Yzl3bGUxZllFRm0rVVlldno1ek51SThoeUV5TXFMZFN6?= =?utf-8?B?a3drYXcyV1p3UWdrcC9DNlczanV5T2NlT0xmdHpJc3dHa2Nqd3doUnFvYjg5?= =?utf-8?B?WGZpN2kvZjVYWWVpU2JWTlV2TncwU2h4MUVmVVRGT3RIeGIrbjljTnlYdGZ4?= =?utf-8?B?QmZtL0hqKy9yR2t1akhRK3BSM1UvNFhDcDBBZHppd2N5cHgvQVBHUHVmYUxJ?= =?utf-8?B?RzFqTVg4RllvWVpFTmVRM0ErZkQ4V3cydS90YldOMVoxTk8rbVhFZXg3R1U0?= =?utf-8?B?aTN4dC9ja05FeExTeXUwYVEzTnJzck1CZzJQOCtvYjlVZmxzYXhkLzl5WkNj?= =?utf-8?B?WFZDamRiUnFQR2ZaL2orWUs3YUtOQkFzemt4V3JoT2hFQ2hwQ1BROXBvZnRr?= =?utf-8?B?ZmRyM3hXWHdNRE8vN0xqcUNVOHpnWFZaQTJ4RWgxZmd0RnJlUzhXaXpjYjNJ?= =?utf-8?B?WjhncGg3SWFLSUxSczExdVNjeG9EVUt6a1g4blJGOWRzVDhhbEZhYi9rMmNN?= =?utf-8?B?QktVZk5mUlhZWksvczZvMkFVOUNrcldOZHhneUhjclJSWDFDa2xSZzFIZi9P?= =?utf-8?B?M2REbnFUNDBwWHh1dy9iTUVrekhwU3YyNUxCbERZZ1UwaVpZcThleWpIaGEw?= =?utf-8?B?Q0pOeUxRZ0Q1RkdqRTVhM2oxZm5HRUdsejZSekxnL1lZTGs1VGp3ODhDZzJF?= =?utf-8?B?dmplZ2FiNHQ2dExOamRhNnFMTnZvcXc2RlIwNjdWV210aFBYZm1ZOHloV2d0?= =?utf-8?B?ZkZwQXVoUW92YU9kbXhqR09GYVdDeFpkc21nZlljSUR6NmhQb2IwTFA0UHV0?= =?utf-8?B?bUdjTHU3emV4eVdRdU1xZnZNeTVvT2IwN09VV29QanF0RWtCQldSWG84Smpz?= =?utf-8?B?ajBNalpWT0VoYjJGS2d6aXRxN3lSV2pBY1RrSGdzRjZLNGtBQTVpandSSjJQ?= =?utf-8?B?Z0lwYk5ra3JUb2NqSlgvaUZNanBzUGRqbXdPTmRIbXRnM1A4QkxyeU9Ea3I3?= =?utf-8?B?VjlYSHYzQm5Pa1dYQ3pPbGUxRVVmbUxGMGZBSitoeFRQOHRGeWR6aE1yTGNj?= =?utf-8?B?TGovQld2WW9zUVREaDZJYzZRbUNxeXpCb3Q5NlR2ZHYvNUNjeXlWSThmOE5G?= =?utf-8?B?RDFtTmRmbHFJSHlZU3FwVkE0cGtHdE5oclVsSG9pUlg5cXRaYW5QMEJNb0xk?= =?utf-8?B?YWhuK2hGNXhlUDNTcTlja3AxK2psdUhIcjlEdG04TkZ5YndmVXRRK2tZbkNG?= =?utf-8?B?cU1OVlpqWEN1NERYRG05TVYxRzV2aFExR3RGNU1OSXZPVjBWa1hxc29tdDdn?= =?utf-8?B?Z2p5aGhEZkJyc3Nsb0hUY0duRzZaSkUzdDY3dVozQjRvays2RFEyRlRMUFJ0?= =?utf-8?B?V0grdEhCa2xVa1JRbjRCRHJ5VGVSZWNyUko3ZkpFZXNPdzk3eC9KUEtUeGhF?= =?utf-8?B?NlA1UlVTT29SckN1Znk0OHNzcmc5aXBBcllYblE1a3M3bTE2aUdleFFPOWMy?= =?utf-8?B?TklFNTlZM3BHekRjaW9ycGRqeFF0a0NDT0ZORnlwWXBXYjFmYmw5eGNlRU01?= =?utf-8?B?QkZXTkV5Q2Q1eWpiR3BGeWcvb3B5U2hiVldNZGRSM2hXTjlvNUtQTjZYQlo0?= =?utf-8?B?SVNMSmFXSmFrNUZjaHZheEtySGk4YmJzR29qMDhteGhrUTBMUEE1Ulk1L2d0?= =?utf-8?B?RENKaGYydkhzWTBDcVBMYUswYVdPVU1CRkp6ZHF4SThIYUh3RmxTeG1SbzlP?= =?utf-8?B?THYzYlRVa01PQ0l3RnZac3FNczg1NVZScEZlSHRlemRjRExYOStTcDBnWmxW?= =?utf-8?B?czFuZUIzeTA3V0xGNTIwRWQrb2NocHVzbkVLWW5UVklCbEdpNEIrY2QvTndB?= =?utf-8?B?bTQ2ZWNYSjNHazNlZ3hWQXhVRUhTalArOGtndHVxblBRR29Qa1laNzAySHk2?= =?utf-8?B?VGp5elR1NHFHRXhjb2YrRjA5RTVkN3o5SGttRHFSc3lScC9WdzIvT2xzZkV0?= =?utf-8?B?Tnh6TXBEWW5aWlV5SGdPNmU5c3RLOVpoRisrRmZtUzFGWWlZeW1xeUdLaHN4?= =?utf-8?B?Q0ZEZlV1Q2dpVElSbDFSc0htOHJqVTJuaWV6T0tUMFFaSEp4ckFnb1djRFBT?= =?utf-8?B?WlE9PQ==?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 1e5ca66e-bf8c-44a1-f769-08dced7c74cc X-MS-Exchange-CrossTenant-AuthSource: MW6PR10MB7660.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Oct 2024 00:49:57.2942 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: MRU6XaPgeQ1dYnsiVE9LHgSoT5ofT1tN7gbkJ1yOwZjxp1Xl1OcpqGghWhjfa4Wn8aoWombzvXxc+5qXSvCnJq+hg25+2jy41C0llKN97xs= X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR10MB6132 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-15_20,2024-10-15_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 mlxscore=0 phishscore=0 adultscore=0 bulkscore=0 suspectscore=0 spamscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2409260000 definitions=main-2410160004 X-Proofpoint-ORIG-GUID: f9WjsTFt0NJ9UCI01d6VWUv-2r8Pi1b5 X-Proofpoint-GUID: f9WjsTFt0NJ9UCI01d6VWUv-2r8Pi1b5 X-Rspamd-Queue-Id: 49EA0C0009 X-Stat-Signature: 4dos3gh87o66mrdbbtokzfk4rgxu41ru X-Rspamd-Server: rspam09 X-Rspam-User: X-HE-Tag: 1729039814-506291 X-HE-Meta: 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 cSHHdmBc 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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: List-Subscribe: List-Unsubscribe: On 10/14/24 1:08 PM, Jann Horn wrote: > On Wed, Sep 4, 2024 at 1:22 AM Anthony Yznaga wrote: >> Reserve a range of ioctls for msharefs and add the first two ioctls >> to get and set the start address and size of an mshare region. > [...] >> +static long >> +msharefs_set_size(struct mm_struct *mm, struct mshare_data *m_data, >> + struct mshare_info *minfo) >> +{ >> + unsigned long end = minfo->start + minfo->size; >> + >> + /* >> + * Validate alignment for start address, and size >> + */ >> + if ((minfo->start | end) & (PGDIR_SIZE - 1)) { >> + spin_unlock(&m_data->m_lock); >> + return -EINVAL; >> + } >> + >> + mm->mmap_base = minfo->start; >> + mm->task_size = minfo->size; >> + if (!mm->task_size) >> + mm->task_size--; >> + >> + m_data->minfo.start = mm->mmap_base; >> + m_data->minfo.size = mm->task_size; >> + spin_unlock(&m_data->m_lock); >> + >> + return 0; >> +} >> + >> +static long >> +msharefs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) >> +{ >> + struct mshare_data *m_data = filp->private_data; >> + struct mm_struct *mm = m_data->mm; >> + struct mshare_info minfo; >> + >> + switch (cmd) { >> + case MSHAREFS_GET_SIZE: >> + spin_lock(&m_data->m_lock); >> + minfo = m_data->minfo; >> + spin_unlock(&m_data->m_lock); >> + >> + if (copy_to_user((void __user *)arg, &minfo, sizeof(minfo))) >> + return -EFAULT; >> + >> + return 0; >> + >> + case MSHAREFS_SET_SIZE: >> + if (copy_from_user(&minfo, (struct mshare_info __user *)arg, >> + sizeof(minfo))) >> + return -EFAULT; >> + >> + /* >> + * If this mshare region has been set up once already, bail out >> + */ >> + spin_lock(&m_data->m_lock); >> + if (m_data->minfo.start != 0) { > Is there actually anything that prevents msharefs_set_size() from > setting up m_data with ->minfo.start==0, so that a second > MSHAREFS_SET_SIZE invocation will succeed? It would probably be more > reliable to have a separate flag for "has this thing been set up yet". Thanks for pointing this out. Yes, this is problematic. A start address of 0 generally won't work because mmap() will fail unless there are sufficient privileges (cap_map_addr will return -EPERM). I already have changes to use the size to indicate initialization, but it may make sense to have flags. Anthony > > >> + spin_unlock(&m_data->m_lock); >> + return -EINVAL; >> + } >> + >> + return msharefs_set_size(mm, m_data, &minfo); >> + >> + default: >> + return -ENOTTY; >> + } >> +}