From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27F6C2EE987 for ; Fri, 25 Jul 2025 17:54:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=205.220.177.32 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753466055; cv=fail; b=pMELYbexjRf4bdrQgx44Q/xXQF6DCphl653VoJhKwVJhIxwc9EpQ24dW1ngf4ku9jofJu7SVyPbYwAmyEpvOIUn+t0C2vf7rnk38KiqO85MncLIZcpMK2J43kUxppm5SVSZmvVHGO0+6qTYFPUsw9b4YpkzqgNjjMF0Os8WpWtw= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753466055; c=relaxed/simple; bh=/13hpDZ6Zv3Rb7OxXXLFVEYa0g/QpX3LhtMoXFnQBEo=; h=Date:From:To:Cc:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=UpsGQp/FLu9pOgafp33Kl3G5Vwf8S8zGkWQdrvRxgAK6LLFSAPrW60k7LG1rQV9NOZtNwy3gbkQe9idsQN348FlXvSeQ5parh7A0EKMwh4aGdA6Jfho/UlM52P9mMKwtbI0z+WNlUNZdDLCcpxf+BDTHepP/EC9MrOD5PJ97JzU= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com; spf=pass smtp.mailfrom=oracle.com; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b=QrUVo3ro; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b=b3QcFzS3; arc=fail smtp.client-ip=205.220.177.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oracle.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="QrUVo3ro"; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b="b3QcFzS3" Received: from pps.filterd (m0246630.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 56PGCAh1000756; Fri, 25 Jul 2025 17:54:01 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=corp-2025-04-25; bh=7IJntZIh9eX+NUCjqQ 9Cc7Lu7BhXpJYP3BpUNewHQ5s=; b=QrUVo3roPS6KpIqxpeZDkfAcoM23mU873N iymJr4Gsphmbs9csnbYlF8FghpmROWN7QtSNfSDgxWRqo2QiZWWzkkfGiUJhbitG HBpVCwTx5RK+TbVpfyoETnCw6NXTnMyrjSNZGL952J4OLpEDeuCZO4n7+LskrL9/ ApBbCCuGwpCzfoliTIMf4r57aL3MASnobhKRfYlpHlQuZSvV220vE3Y31cg9uyeq t9d2C+YcfM2AACDWeVXuvdUZMkDkquBxd/LmkJS3LRNlwCMCr+uJXrundtZRO8eA MzFWqyCgOmu2t2ArwzNCrojPzUcliVsyQmbanX7ffPMQ4JGAfgCQ== Received: from phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta03.appoci.oracle.com [138.1.37.129]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 483w1n1h1s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 25 Jul 2025 17:54:00 +0000 (GMT) Received: from pps.filterd (phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 56PGu2JG011395; Fri, 25 Jul 2025 17:53:59 GMT Received: from nam04-bn8-obe.outbound.protection.outlook.com (mail-bn8nam04on2077.outbound.protection.outlook.com [40.107.100.77]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 4801tdad50-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 25 Jul 2025 17:53:59 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=O2njCyXmXsQF1htzgk+ufaBMZo9IuJDWFPvmvkJNH+8JKihMyE4X6FpvQclrCKw5Vl4f3Kcnrjl9/hCiib9litevjERKXr+4aGp0sFcCoTWRFe8tmh1y+rAxQnoIZnT+iGmPBJQm7CIKU9XuWClwJR4cerm3v9bXa+LlWu9yP51IPWhu3fAUT3WGP4Drc/xfZOasFpYyEsKvorQqbnP1895rTUj6lxTbuo728DmfaOTNV4C0YijwXDdlxrGBkE2dfJ7Z9o8GzfDZzh+aNkhQp9DKSv4RgEfZ29mCyfCvcqIpzY+ptf6i+CKel1nVZTl/14jN7u62w20yOWLQ8w5MEA== 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=7IJntZIh9eX+NUCjqQ9Cc7Lu7BhXpJYP3BpUNewHQ5s=; b=AsaPNRXXi3AHym+FZrr93zu0paj294tnLXzkOnAeHSnSlIYPxkcIBtyPD6ip2e1nswV5Qa60aeHwoo0lWMe3fGFCqVq+spXlrdrdLKjTEvXLkn1asfSkqmDMo6y09YLY2oWFtUV40vCfzQMVO5SlEjpoC6g6+RJLoYzynd5jPGZgu7k1EfzXJkSQvI+Q2ohjSP0BMcDcWo9lWn/nMoGFv0aIuzJkQBvtywWgMJWTG+KG1f6si62ykiEp9MvN/YBvDYMdE8paXxvL7TiOLeJ/dbUqSHypBzaWoAgUV/XQ4QiRoCu0wsjoiKaymPl9u6jppJCQYXHRCzyTFYC4X0rnfw== 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=7IJntZIh9eX+NUCjqQ9Cc7Lu7BhXpJYP3BpUNewHQ5s=; b=b3QcFzS3pkC/AkvmR8G5y07I0Q4+QkMrhoScBproj8m++pOn8OPHNs4adAGXgWu9CdWKRT9d9mNTxY4Xtb+/XAySM8/CGyK7DQ87SmLsVszT6xMnGzjZ17Ej1gvV5oJa+i9tfDSIt/OlM/OuIdw482/wMnVuSpEj+oaKYUE1fCU= Received: from DM4PR10MB8218.namprd10.prod.outlook.com (2603:10b6:8:1cc::16) by CH3PR10MB7186.namprd10.prod.outlook.com (2603:10b6:610:125::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8964.22; Fri, 25 Jul 2025 17:53:56 +0000 Received: from DM4PR10MB8218.namprd10.prod.outlook.com ([fe80::2650:55cf:2816:5f2]) by DM4PR10MB8218.namprd10.prod.outlook.com ([fe80::2650:55cf:2816:5f2%5]) with mapi id 15.20.8964.023; Fri, 25 Jul 2025 17:53:56 +0000 Date: Fri, 25 Jul 2025 18:53:54 +0100 From: Lorenzo Stoakes To: Jeff Xu Cc: Andrew Morton , "Liam R . Howlett" , David Hildenbrand , Vlastimil Babka , Jann Horn , Pedro Falcato , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kees Cook Subject: Re: [PATCH v4 2/5] mm/mseal: update madvise() logic Message-ID: References: <492a98d9189646e92c8f23f4cce41ed323fe01df.1753431105.git.lorenzo.stoakes@oracle.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: LO4P123CA0259.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:194::12) To DM4PR10MB8218.namprd10.prod.outlook.com (2603:10b6:8:1cc::16) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM4PR10MB8218:EE_|CH3PR10MB7186:EE_ X-MS-Office365-Filtering-Correlation-Id: 7d9889d0-e70e-4e86-8f85-08ddcba43a23 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|376014|366016; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?C9BnAhcTJGHkDWOobRm7KMRer6szy3xr/xav6tAW6FgwFVrvMLGfmNFED9z1?= =?us-ascii?Q?dv88QNC85t+XUzLbPjh9gv5FocHK7PJpwxf6Xh9ObrWF70GMxScsIDa2T3EF?= =?us-ascii?Q?N9o9PN5/sJdn4a+4dSQjRpteYta0GAHRDsSpqUJcYkk2CKRr1+oaZOf4bLsx?= =?us-ascii?Q?fMQdJnMgBRgYo7ontHFmSAyNdSUHBsgmI1A4z+AbCZTmyKRLigdWoHCc1W85?= =?us-ascii?Q?4pWyqIdclbXXHxmbIb1C52JIJ5Ei7weM6NziCRCdoULX3F9cJHvSkU43YcrS?= =?us-ascii?Q?riNdc1Pr8cGSlc9o6AWL/z2g6VlcxUAERbxVcLbogeVDQ5cSyASSPYbPHUe3?= =?us-ascii?Q?29hS/E0yvH7RzIo53qU+Rh8bum6t2FX7SKHXKxQDvKmdjdHvTUD1S7HsbUVh?= =?us-ascii?Q?UUwuMkNpj+VjQqZujq9VNWTe7Jr5ajyjbcMU4l+Dui2LY6wxp2vNTimcKnqr?= =?us-ascii?Q?mXP3g3Px7nifViTIzzSggG/TN+FUIZVlpn6GIjid/hMLY3PT+8Wp+9OaZJGh?= =?us-ascii?Q?pSEPGdOiFhOeEB+p9baGSFKIcQHSLUOtMm7Nehi6OCruKNYnczfwXvfxp5BR?= =?us-ascii?Q?vItNJz1M5umf/yfG9jxAL6dfvxJmGA9DBQa/Zw+V9RRM2N7X4L+BheASouuc?= =?us-ascii?Q?hRGrYac+kf3ozfQx8rLAd3g5xZKALNi5vvmLj91wjGb9IV2ekeZKeI2ZBe9a?= =?us-ascii?Q?wXjVs6JgATwRXeTn4Mq1BDRylpOfTm8kev7Vn2B3zB3BU6Z8JU9ih8Wv3oYA?= =?us-ascii?Q?W2ehITMCo7PjsKNwfF5R7VDbn2MzYhDm/WBN7TvQLq0Al7DkHht/lVduAF+O?= =?us-ascii?Q?+ErsKHRS9cQ4kNmJ/dg5w8Dr6s/aJuBDbNRY6d1wHhzHBQR54d5vaVBcjHpR?= =?us-ascii?Q?SQqwYvo5IjsIOHcWsI7HvEcs88Mo+38TuVfL8Fcr12RY46FmGlpjQm6jDoFe?= =?us-ascii?Q?a83qPprL1+kHrA7BTIMSnntqmrCNfwhS77UTUe2HAEgPz+vROpi9sAcfIOyo?= =?us-ascii?Q?wsXv1B4HnPiJxs0BYmNXg3MmnidZH3i5sjjbBFAG/sS53Jd4hr9xJeseVcZJ?= =?us-ascii?Q?v9qOe7t5AXrjKylqhm3mmwqEGZTlGqIhnMEgMGKgaZ7foFNNapC9hPL2/Cf2?= =?us-ascii?Q?mK62efucn/Q7GR0BrLNFHD5XD1N2INkANU+WtvAB2IvNgiPqP6sWIV4q7EKT?= =?us-ascii?Q?1Wwjk3eBcjOXvw/c+YQTEFuCJ9TAJ3zNq2GxJDbuV/5teDxFx8UO+YrWjpWF?= =?us-ascii?Q?csWDzk7HzxtnOxzeaLbI6gBW9Uz8P7WsDAw//BM5N7aSKnsZgeNWEUPyMP3o?= =?us-ascii?Q?zt5mzKi1Y7C7zSAvwuK8P60DFI5czGfDujVpMuLt4PoOz3aCZ6PM4+DjhDgv?= =?us-ascii?Q?daZLukqhY9DA8GzFwBRlToNj/lttocWr797VcSyB67uKZKtDjA=3D=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DM4PR10MB8218.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(376014)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?LYobtwP/Be3nytxrxqkzliLOfZh/KofhpuJMtrn7ISbHAXsCp8fx8ZGZj23R?= =?us-ascii?Q?GSSDSNLImgLLjgV70aQAFzO36jO5sn5GJH4p86Iv+ab53JggzqdCGP3du4vt?= =?us-ascii?Q?IQoR26KgRFTUpx55oxE9oqvB3oLvHsQAmMqe9QRjgtN3goCDmA7h7M5Fr8XJ?= =?us-ascii?Q?V2ihSZfi5sLKufqc/t5qW/smjVCRPnMQostdfOVonS4ks7Uz2flseUEtumRt?= =?us-ascii?Q?pukbmjy6x79mSrmr+tLJnD8P/brsksx0sUnQ7KtxFvwt1kZ2mh13hTKbFdvp?= =?us-ascii?Q?kMVTA/WJMr3E8dQErzVMWzFkmSduQtDXJvVjEpNJQzpz77u34s4okO+E0SMU?= =?us-ascii?Q?ARAnZ0uMmfN9PCOjz/VDFPIN+pSC7vjiGYXTdtIVZRkzLNBwsBAO/EUnr3cX?= =?us-ascii?Q?KyIdIQq06nJaXch5wYN1FFTYe1yUKCtiqu9EV3/wIWZEH2Qlb5P8fbw8gGOS?= =?us-ascii?Q?+7YHSPAyBJrh4X6PF2b5A/6MC+ZGLmLJZvxsidAUqi70SGh2DahtoQ8uYU85?= =?us-ascii?Q?VmdCyRzUZ/br/h2INQVWq6FunTwRZ9+WvtBD9LpQsLTXGD6XNVVUtf99Ecym?= =?us-ascii?Q?8+tbVMMZprkXUg9g4avrmYeGkspOesTuwFPyBPDeocjIUrrb91pTEeOfluRU?= =?us-ascii?Q?VttC2CHV0PGSpMZEJGl9vcnSU8bw1iGkOE5xXARsQN3udojtnL+sHimi2B57?= =?us-ascii?Q?azGzI+LC9VOOvVYTZJgeyq7YOgieYlQRPwkCwmPW4a8XEGekz6rQ66hVGwl2?= =?us-ascii?Q?VqZwAHjlLuDMvOGGxuPMK4o8KH9gLVKFKMWWN400OMCo9vULn6q8ovyT9v/m?= =?us-ascii?Q?vMd+ZCXhKXIwjUvPjuixvvSL4N0PGjbrQlYo6YqdHFbw8ILWd0tuGIrZ6Nsl?= =?us-ascii?Q?axhDkwUYmcRuDcPK6hux6Zz0pZaw81B91ek1jq85FakrAOY38SgQldVmoFWO?= =?us-ascii?Q?XVoiwInycies4lyda9Z+P3YCUJ0S8FeSrpJfUIU2hof8bdSdualPl07l1ldB?= =?us-ascii?Q?427LnoG/ud91jf5HQGN6JVMO5Ksg5M8ZJJS3tzDm+LHv/TLzC3lfPKP2Sn6r?= =?us-ascii?Q?0WK4Edlw7B1DU0Uz/1PGYmbYyoXYqhmU9YeJdeReuZ6z1vVQAj5ljOtBsfQm?= =?us-ascii?Q?VWXkj0GH8tspNYiWbq+NPiVVoXHVGTxq24Hhd7sHhpqf/RLLaXtk5MDGiN94?= =?us-ascii?Q?KCQTRrVizp2wgkhBGr6qSht3KV3Iy2iFRoRL4BMGmGJi20JVYxs8rPk5Pg+x?= =?us-ascii?Q?HCc5cblfITDQOGvYFtDuWh5JeLEHOdD9fznHBj1887WamtjG9LjV7SFeNHqj?= =?us-ascii?Q?xbPsf8GHJzC7Z+CW4w674c+/hj0bkVu4wUEX3yjQU/P0uTWqRbtsB92ICon9?= =?us-ascii?Q?Tbr9CyUE1NhCURWYPStFdXBAawMePja10aFumd86KSHwHxWlxC9KHwtHWV+0?= =?us-ascii?Q?C1S79qbrTA/k/VhK7mTBrfwOyZke6aUTec24TAtWIjddhyptaqszScXgTnbY?= =?us-ascii?Q?UKErZfyG+YcqVlPvXCsYqEzZxH3iGRwgI+C0CW8dziWBtVpRWfDUcVHA0Uyw?= =?us-ascii?Q?BFykl30kxh+Spr1nbYFb4GA1xU6fdcKqYP/O/ZPDmiL8juwBFm6j2Bxa8yMu?= =?us-ascii?Q?Sg=3D=3D?= 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: 7d9889d0-e70e-4e86-8f85-08ddcba43a23 X-MS-Exchange-CrossTenant-AuthSource: DM4PR10MB8218.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Jul 2025 17:53:56.7623 (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: qvMnCtTtq6LWl46VXBtIYFLiTs8gFF/keaJMMuU3W3ZKu7Va9GP04tjhStwInaEsJnG15Ke491JY+FIBQ5E6NEGtwB52mHNx9ndRViTYeMk= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR10MB7186 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-07-25_05,2025-07-24_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 phishscore=0 mlxlogscore=898 bulkscore=0 adultscore=0 suspectscore=0 mlxscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2505160000 definitions=main-2507250154 X-Authority-Analysis: v=2.4 cv=ObmYDgTY c=1 sm=1 tr=0 ts=6883c4b8 b=1 cx=c_pps a=WeWmnZmh0fydH62SvGsd2A==:117 a=WeWmnZmh0fydH62SvGsd2A==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=wKuvFiaSGQ0qltdbU6+NXLB8nM8=:19 a=Ol13hO9ccFRV9qXi2t6ftBPywas=:19 a=xqWC_Br6kY4A:10 a=kj9zAlcOel0A:10 a=Wb1JkmetP80A:10 a=GoEa3M9JfhUA:10 a=MDOVkcc16J-QX9dizX8A:9 a=CjuIK1q_8ugA:10 X-Proofpoint-GUID: LFHWFVJcRZ8IaMFqzvGPdGhGi6fb7nYK X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNzI1MDE1MyBTYWx0ZWRfX1cGxDJuZMEKX egvGjgSQ0Tn5KTtW5c/47pysT6D1wf8cmkTk5bMt1ZQ8boScWJY14B2UYZu7cdVu3zH4U1C/Pse wOE4fKAnfDYETjXIO+SIg4Dx3V3EeykUp7N+UMGLrz783BqGqt45MDyI41rLJcYvC1PsVfWya9V QTrrrArjr8uNlkMPb18dGfelDONHlD/G5CIwPGIyKOVt76GkSlas67BGD9RPWfNqLuwlQu9FePI Cew1dWOF5jpkvo2TBtOEa/CvN7CWlm7TLaq03SWlDKM4voA5jruo1c5Jkuc2OLTKRQibbtPCcr+ 0rtJcQE/zfzH8B/JijaTHlJb1L7X/r6fNmhi8uOR8COiMeNxvO1oEVn5kfnywyQxLDpcdHusnDD D+PlAdff+WzXQ20J3//ZNhjil6ugdnYj+nwokBFw2QquQ8KdChhifXXtTfolwqL1uyFKgUGG X-Proofpoint-ORIG-GUID: LFHWFVJcRZ8IaMFqzvGPdGhGi6fb7nYK On Fri, Jul 25, 2025 at 10:28:57AM -0700, Jeff Xu wrote: > > -static bool is_ro_anon(struct vm_area_struct *vma) > > -{ > > - /* check anonymous mapping. */ > > - if (vma->vm_file || vma->vm_flags & VM_SHARED) > > - return false; > > In this patch, the check for anonymous mapping are replaced with: > > if (!vma_is_anonymous(vma)) > return true; > > vma_is_anonymous() is implemented as following: > static inline bool vma_is_anonymous(struct vm_area_struct *vma) > { > return !vma->vm_ops; > } > > I'm curious to know if those two checks have the exact same scope. > > The original intention is only file-backed mapping can allow > destructive madvise while sealed. I want to make sure that we don't > accidentally increase the scope. > > Thanks and regards, > -Jeff Thanks, that's a good question. So for a function to be mmap()'d and file-backed, vm_ops _must_ be supplied. You can see this in the fault-handler: do_pte_mising() -> do_fault() if anon -> fault anon otherwise fault file-backed So if this were not the case, you'd have file-backed mappings going into the the anonymous fault handler logic. This covers off MAP_PRIVATE mappings of file-backed mappings too, as this is handled in do_fault() by: } else if (!(vmf->flags & FAULT_FLAG_WRITE)) ret = do_read_fault(vmf); else if (!(vma->vm_flags & VM_SHARED)) ret = do_cow_fault(vmf); That does the CoW fault handling. So the vma_is_anonymous_check() here should have the same semantics. Cheers, Lorenzo