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 4AB40C8303C for ; Tue, 8 Jul 2025 08:20:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B734D6B035D; Tue, 8 Jul 2025 04:20:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B23DC6B035E; Tue, 8 Jul 2025 04:20:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9EC206B035F; Tue, 8 Jul 2025 04:20:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 7E0DB6B035D for ; Tue, 8 Jul 2025 04:20:25 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 120DD8049F for ; Tue, 8 Jul 2025 08:20:25 +0000 (UTC) X-FDA: 83640400410.09.EB92395 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by imf09.hostedemail.com (Postfix) with ESMTP id 97AB3140006 for ; Tue, 8 Jul 2025 08:20:21 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=aBf9AO8n; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=YQScRiPk; dmarc=pass (policy=reject) header.from=oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf09.hostedemail.com: domain of harry.yoo@oracle.com designates 205.220.177.32 as permitted sender) smtp.mailfrom=harry.yoo@oracle.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1751962821; a=rsa-sha256; cv=pass; b=Yh+oyX1j3BEcPHE+QBr5dbzxjb/d0KrYOatVHxgGSdm+t0PX8KcpC9qlzu7nCIFWbAvBpj juFa/3YVovRFVmTHrSDz9HV54Su8sANV7B7crzJYDNSqdDX/KjkRpj4qGqggGAhF4x6L9E gbJfREDEAIfdTy00QSR/SqmxlDofrJY= ARC-Authentication-Results: i=2; imf09.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=aBf9AO8n; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=YQScRiPk; dmarc=pass (policy=reject) header.from=oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf09.hostedemail.com: domain of harry.yoo@oracle.com designates 205.220.177.32 as permitted sender) smtp.mailfrom=harry.yoo@oracle.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1751962821; 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=rWCE3BsHMewx+EBtk7LqHyQkX+7dL/+MC/46L8uh4P0=; b=cLFn/3Fbuw25JLNNlfMpq/hXKV1ZSPQsR1a6KzsQTRBR4b/Ss/fyFMpu6xptwrHQH6bHok IaolzRMzkpNk0GWlGeo/9Bo/0LLxB7x982ErxJslRQ5hCDjBaNQowf6DaZ+G1hEXsiYO7w OOxNuQCyCTWQJFy1FwWcORIDjxEq5fE= Received: from pps.filterd (m0246631.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 5688GwWe012895; Tue, 8 Jul 2025 08:20:08 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-2025-04-25; bh=rWCE3BsHMewx+EBtk7LqHyQkX+7dL/+MC/46L8uh4P0=; b= aBf9AO8nU2Rnsi+Y5fmJGa5ioaOkLN5FeC6GxWspFQuWYy+pagJwfFwmu5i/Xzyg B933EGXpXteQVs4RkkK5yrRzNt+u+w8ZmfC/AVUjkx/iiP9CZL4Uv68zifzwClG5 524yzDNwzfKqyrizqB/CX3zhu9Hea3jxRN8N12a9CIUdu/e9VNipyWtP26HUl3Nd z02wLAR4xK37if4X7BBsRuZTXyyPozsil6IrAofCJEfEeY8LoIKtl9tb7Z5cdrJh ZXs8OMJ8gYwo7X5/HNUNdvL+Q56G8cMQhBTGS6dYM4yeTffTZQRoL069ac/TtG5n 7H6ECVSIzXKF4925o2mAaA== Received: from iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta03.appoci.oracle.com [130.35.103.27]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 47ryp5r05k-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 08 Jul 2025 08:20:08 +0000 (GMT) Received: from pps.filterd (iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 56870FKd014057; Tue, 8 Jul 2025 08:20:07 GMT Received: from nam10-dm6-obe.outbound.protection.outlook.com (mail-dm6nam10on2082.outbound.protection.outlook.com [40.107.93.82]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 47ptg9abab-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 08 Jul 2025 08:20:07 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=fSWqZlMMwdSFSOhoPr6RsnOOeWD7ohXZVOlE+gt6wc0CaBfyqmzCBk+IkQSMcDrPZ2H70iWASG0sFTZXphlQDglDs3C6Fk4VVdvDg9aOzjEyEAu8JlINsp9gfmHvRs2ZXFdKxXWr1K6evuff7XGeHAfJdzdeTObRrhYqj9AQ5vmAgmuzj3AhAmIiIGwODTZhA8ORZ/JhWiGbYtAW+wYbPvU9yA3gDHENsLZ9KaCntHV2RJxTJQ7J6IZTv/8jSzQ6FrS1shtfXoa0WdwXAmmsF+x/uVdWK+EElXrwWBkhrC4ke+B9m+5kb0k0iAFyvvju9RUSL2cYK3wQjQvLdjTcsQ== 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=rWCE3BsHMewx+EBtk7LqHyQkX+7dL/+MC/46L8uh4P0=; b=yLoCvwK2p/nhJ0MAAPysuTVTEGOoTqtSFllEJU/ahlkCEe6GghUJ6jtvI/idVMtF9hB9dyTRQ+C79s2c51gAKSH+cR+AS9Z9EKPYNCLWB0ub0wcCN0fCoBq4JjeCm1oq1gDxN82xaxRlUkc+95GofA8DegCNolsZt7BeNz+Mk5AjWryZMkU85Ph8mM3rTSS4mZMQnNTB72jznZGiJv+EviBjjkM9EvQTvYx5wGKGHzx5vA3MKFSSxEX9nZVsu296o0qt3qcHWduIpQEAONDL2SUs9tUSGA+JRx68sxilq5k7lOQGghLKbScS9jJ6ZDD7K7dMx2seqnBF9HrGPUvJaQ== 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=rWCE3BsHMewx+EBtk7LqHyQkX+7dL/+MC/46L8uh4P0=; b=YQScRiPkeLc2YgQdcr3b6R9UblQOip22oUC4vp1jwz/DAWNVjylU0UpIyBU7yi4G5q5gArFwTui7IHswKMrpFEyJQ9vtRSnVfmjANAEvTQV8Zo1cDe9sLzUMdyvM3RIJdTTF3DQ6mYOe2IzhC/fB+qTm02JlRloXRp+YMHutDzM= Received: from CH3PR10MB7329.namprd10.prod.outlook.com (2603:10b6:610:12c::16) by DS7PR10MB5197.namprd10.prod.outlook.com (2603:10b6:5:3ab::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8901.23; Tue, 8 Jul 2025 08:20:02 +0000 Received: from CH3PR10MB7329.namprd10.prod.outlook.com ([fe80::c2a4:fdda:f0c2:6f71]) by CH3PR10MB7329.namprd10.prod.outlook.com ([fe80::c2a4:fdda:f0c2:6f71%6]) with mapi id 15.20.8901.021; Tue, 8 Jul 2025 08:20:02 +0000 Date: Tue, 8 Jul 2025 17:19:48 +0900 From: Harry Yoo To: Barry Song <21cnbao@gmail.com> Cc: Lance Yang , akpm@linux-foundation.org, david@redhat.com, baolin.wang@linux.alibaba.com, chrisl@kernel.org, kasong@tencent.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, lorenzo.stoakes@oracle.com, ryan.roberts@arm.com, v-songbaohua@oppo.com, x86@kernel.org, huang.ying.caritas@gmail.com, zhengtangquan@oppo.com, riel@surriel.com, Liam.Howlett@oracle.com, vbabka@suse.cz, mingzhe.yang@ly.com, stable@vger.kernel.org, Lance Yang Subject: Re: [PATCH v4 1/1] mm/rmap: fix potential out-of-bounds page table access during batched unmap Message-ID: References: <20250701143100.6970-1-lance.yang@linux.dev> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-ClientProxiedBy: SE2P216CA0180.KORP216.PROD.OUTLOOK.COM (2603:1096:101:2ca::11) To CH3PR10MB7329.namprd10.prod.outlook.com (2603:10b6:610:12c::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR10MB7329:EE_|DS7PR10MB5197:EE_ X-MS-Office365-Filtering-Correlation-Id: e4f966c0-c49b-4ddb-0232-08ddbdf83ca4 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|366016|1800799024|13003099007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?ZHg0WW1KK25sVzV0V0RDczdwZTNpVnRoQXN3WEdKVHEyOHJuL09BYzR0cWpn?= =?utf-8?B?OXBCOC9uMG05TDJ1Qi8yaEFaMVRldWkvL2dtRk9zSnc0WTFxUXdaOUM4Q2RF?= =?utf-8?B?anp0a2lkeVp4U3hkUEZ0SXdoMXFWLzNKVHg1TllnNVRuRFFsdTNjbzJuKzJn?= =?utf-8?B?SFlUS2xBVzkvRGFDUGJKNURudk1UVUFuS3Evc1krL1Z0U2FUS1BBakNrOVVT?= =?utf-8?B?d1h5VlAxUG9qWDN5bytoREg1TTFXcEJGMG00aHB4RklZMHB4ei96amNmSEhS?= =?utf-8?B?bWVjZ1FyUWZOd0k2ZS9QMWtadCttNUtxbjFlSkhJaGFTa0VSQ0s2L2M1UkZ2?= =?utf-8?B?NmJqRVV5VnRzdi9tL1dEWXlmNFMwS1JwOGM3ZDdQMUhzZEVRRHVLZlpKTU1a?= =?utf-8?B?TVdacndEYXpLS1UyL1NqMVgzaTlaMWZySVBQNW1WMW91WXBQTFBsZkhkUzh4?= =?utf-8?B?eG9XWldxWWhCZWZvUkIyc0poVm9qcjRCWERkQzJsWHBiM1dDbUUxSWZOY3ZP?= =?utf-8?B?VTdaZTI0Q2lHQVVma3NQN0xlUlJpRk9nZDdiaUl4b3phVkQzS3kvbDZKanVJ?= =?utf-8?B?NGhwMXBkRmcxaDNiRTR4WS9WNEZQMmg1MStNZWpWU0NSNVgwNzBuTmQ3emRj?= =?utf-8?B?Nm9uSVFkc1pGcDgrNHl3alhGK0JFcEpqVnV4blBLaURoLzNQUXo2SzJqVXVm?= =?utf-8?B?aTczQ1FYMUhHaGtlMHh0K1U2WHB6cEVJTVZibmpWaHF4eGhUWjdQeWp6aWYx?= =?utf-8?B?UU8yN25RUE1TcXlESmZrYkRScEdJa2QrT0ZPNUV0eTJUKzBsWjZlblFVZ2U3?= =?utf-8?B?ZU1mMHhPQ0EyRUZxOTd4Z3hDbnZKZ25RMFJXd1JleVNmS2VkMDJaWVdpTkha?= =?utf-8?B?K1V3aDh5Vk1NN1lzQWVGbHhLaW8rdGxrWUorek9LVUtpSktwSnBHaU9FWmFU?= =?utf-8?B?VGRQZ0M1dmpCdjVLdUd6L3JCczQzK092b3RDb1dxR0s0WVVtVC9sZVlhTlpV?= =?utf-8?B?NkNZbkZ1UTFCUjJ6Rm5hZFN2T1NoNjZLelJ0MXIvZFpxZEhxZ09SaEptcDJr?= =?utf-8?B?cWF4L3R2d25wWjJJQXZKWGl1VURscUtmQzVhNHE5REYwZU43RjFqTGhYZUxT?= =?utf-8?B?T0srdWJoWDBhUk9kdGIzNTluNHNaeFRzNkhvRzcveGg4MWVER3hCVFEzRnM1?= =?utf-8?B?S3dCRmlyUFhJaGYzMlcvTjMyTVRmR1RWZXFvOHhBM1NiblJqbVBtZ3F4THhs?= =?utf-8?B?S2VCd291Q1kzNlRZMHk4VmhxQ1lPZFJkN3UyK0U5TE40Z3AzcHl6UG5seVNK?= =?utf-8?B?S1ZCVFNjRDV1dXB0ajNlTm9JNVNmaWZ3T0t6NHhMcTRISzRLY3ZMVklwYnR4?= =?utf-8?B?akdway9pbXJKNHRXNCtWK1JGbDVBUUZYbVE1WGlVbXUreVIwbFQyK2hHSnpH?= =?utf-8?B?aGtvVlgzL2U5TFRGYkxheU5kY2ZrWFk5TTYrV0dJMkFGa29WT2dqSlVEczRS?= =?utf-8?B?SnlnQldGeWEzRUp1bXNCNG1JSDd1QXY2QU1OQS9VNHlPbW5CVVIzQ1d5ditH?= =?utf-8?B?WGxGOFd5aDB5OHRJeXN2aW9idk5vdUhrMTBaWWJuWG5FWWR4UWZadjZEUCs4?= =?utf-8?B?T09uVGlNTTRpNmtENm80WTQ5ZFBnV1hsb1hRUk1sSXRSczdOMUcxVnRHZjc1?= =?utf-8?B?SjNQeStPT3NZa0lMdkZDTkpnRVNhMXVHVUtJOWk0RmJuTGlpSU00d1NTcExI?= =?utf-8?B?M3NIN1pCMm0rVUpLaG1qLzNzbE5yTmx5SVpiUnl6aDVvQ0tqcUlqVlBlK0Nq?= =?utf-8?B?MlFHd3JIbFUvV2VBOE44ZDRoekVmUm5kVlJzWmNmYWFtNmZjY3dxZzNReUNk?= =?utf-8?B?NUlKd01vSDZEZWZtWHhwcjkvR0dnUXFMNU4xRWpKSUdKREJPblU5eXZkZVNW?= =?utf-8?Q?L0YRpnBTdoA=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH3PR10MB7329.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(7416014)(376014)(366016)(1800799024)(13003099007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?eHI1S0JBUnBtSUFVZkpsWU9SZGZzUmlpNmRsclc5UGQyNUF3QlJ4c0ZYTys1?= =?utf-8?B?Tm4zVDBSYzZvMmE0K3drSDZvT1RTVFVRb0lQODBxamwwVS83eUlJVUlFNmdl?= =?utf-8?B?Rk14dnNHblFrV2dTUGdhUzQ0RVo5UVJCNDhuY0NTTStrZVhTWEhXVmxNUnh3?= =?utf-8?B?Vk1HQzIzZk40T2RoTGJtYUk0aFRyNVVwSnZVdi9uMmRzeUpqOFBiOUJTQ01T?= =?utf-8?B?eFN0WmhRdjRkVUFVYWRObnlXRVhNOWVLNGg4VU9OY29hT3BVUjZOK3pVc0Iv?= =?utf-8?B?NkQ2NEpmdysyUTNnM1BvU3JwbG5QcHFSUHlPTTZ4TzZ5UnhJRmhpNHhteWV3?= =?utf-8?B?VFBQUjRqV1l1Ry9Yd3RxTm5KN2JNaTRtVC9SRGNlT29pUFIyTThwVndGVUlJ?= =?utf-8?B?TlhySll2emZZUjdqQVFQL2J1WGM3dXBBdVNWbVlxenlMNWRBNExmNlhLT3Jl?= =?utf-8?B?eXBoSXZTZnV1ZFoycUo3bzVnbkR0VXVuKzIyOUVKS2JWckppNDMrUFRNS2tO?= =?utf-8?B?MVpHVGR0MkJEcmIyRWl0WVowTnlHc3gxeUk4ODdIVjBNNHVHWStHYUR0Tjcx?= =?utf-8?B?NG5QR0JoVWJKOGtPcEpzTUhwdk5iL2FLS1pNclZrYS9vQm9YTnlpWnQwRGxG?= =?utf-8?B?OTQxK2NmZUlucGNTWkZ6YVVvaXRCT3B1aWhwVmtRUFdHWTh3bEl3dVpoV3c1?= =?utf-8?B?S24zSUx4ZmZzNEFGV2x0TEV1WmZrMlQxM1FQSS9JbjRzbm51YzA1MmpVNXZH?= =?utf-8?B?REdLMXpYbHc2V0d6VnNkZlBlR0g0cmptWEgrc3RhMVlJVldJZXQ3empZM25X?= =?utf-8?B?UWlEYkpveUk5dmNCaFlpNTdlVTBjS3BvSlFQTUlyajdHK0ZzRHhKR2hEUmZ1?= =?utf-8?B?bE9KdFpjeTVvYWFjaHRHSm1PMUUyeW0ycG5ObVFtekMzN1E0cnJsSEdSU0lN?= =?utf-8?B?RW53aVphaTRiQXZCVWluWFMzT0tTbHZTSmYwdFhXL2plNk9KZVJFdGdaQ0l0?= =?utf-8?B?R0l4cnNkdTNCOU1IU1JxREJraHIxMDl6SVhnSXdVZkgzdDNsUUpyOHB0ZTIv?= =?utf-8?B?cWNvQzhoQ2lxSlN0Nm5SOGVtWlZuYTdxS0pObmFGdVBicUdOVkRBVnIyUmRj?= =?utf-8?B?V3FMb3A3LzVvckVwNzNINjVWczNkVXdVdjhkTnRqdWh4RDBDNlNLczhVVDZS?= =?utf-8?B?QWNMUjlHTnZCN3cwM2J4QVBaUCtvV3pHeXdRaHVScUl1Q0IvcTR4OXBoN0tK?= =?utf-8?B?RFRqVGVWZTA0Y3hxTHdzMWEwSGFiNjVnSjREQVZ6U3Jpc0MvSUc5V3JrVmNm?= =?utf-8?B?bWxPN01yemlYZjBTSEI4R3p2cGs4N1NheC96Yit3QXpHaHNpYkUyQWhwTldB?= =?utf-8?B?SDN1RHFVQmxrV3ZlWG5ONzg3MEg0UEJROHl1dXhSQVBZSEozRGRsSGxCQVVt?= =?utf-8?B?dkVacGdBSVhEVGlWdTdXQjJyS0QrRkhJOTNzTVNLeWl2aHJLdzE3WWpuVnho?= =?utf-8?B?Y2pwWUdGWU5HYmlZMjQwL0pEOFo3R0Z3cWswZWFZUnRSUVRMbXpORVI0aG5h?= =?utf-8?B?WnB1V0U1amk2V2M0UWRuUVVkRm9jRFFLUFA2Rm5VVHgzQWZmMjJ2cTdJa2FN?= =?utf-8?B?NFZZbUYyT2lCZnl3V25Rdk4xdFdSdGhrbnNEdW96c2xmeFh6UnJCT3lWeGZ4?= =?utf-8?B?Z0JiK3Zya1dTQTRSU2N3aXN6MXBlUlJtSmVvSTJ1QkUwZnN6MER4TE42TXQr?= =?utf-8?B?dHYwbHl1ZlJ1WjY1OHJ0dHpCbWJ1MlRvVVFETkRUYVBPNmIxczNQVjdvWjBT?= =?utf-8?B?MWVjcHRiU1lCZlROSTdaOFBNTlI1KzdmTjI3eVMySWNCZ2t4eXAxTlZKdVJD?= =?utf-8?B?bGZ1ZTRZZGIzSkR6RHMyZGhsN0x1NXNkL3lSRGhNbklFdHg5anZ1U2ZrV3M1?= =?utf-8?B?akczUWNHTDRnMHc2cEhtR1Z0K3JEYnJQUnpkamtmeTRya3loT3JCVk5PbU1Y?= =?utf-8?B?QXFkLzhoQ0lkRkQ5UW80WjN4My84MElKUS9KaHoyQ0JhN1RuNGN3c2hFeGc0?= =?utf-8?B?ZE55VWNaejh3aVZkZHUzazVlWjRHTXAvblZ4Y0NXU1c3N0RaSWpuai9IQWJY?= =?utf-8?Q?k6jY6ExtxojlS7AELcZvKcWuP?= 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: e4f966c0-c49b-4ddb-0232-08ddbdf83ca4 X-MS-Exchange-CrossTenant-AuthSource: CH3PR10MB7329.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Jul 2025 08:20:02.5589 (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: J6HBbraGYpR5wK6x7NNm95TLVGjuosZV2dRAGOtHPCExDKquMpb62sCraax7WC/4WFHgwtmIpM48doZeHsJLDQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR10MB5197 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.7,FMLib:17.12.80.40 definitions=2025-07-08_02,2025-07-07_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 adultscore=0 suspectscore=0 malwarescore=0 bulkscore=0 mlxlogscore=999 spamscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2505160000 definitions=main-2507080067 X-Proofpoint-ORIG-GUID: _jXjmOEI3b0sOih1yqCSAbJooBlWdHAU X-Proofpoint-GUID: _jXjmOEI3b0sOih1yqCSAbJooBlWdHAU X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNzA4MDA2NiBTYWx0ZWRfX0xXZDKqUDW2h 3dOuc7Vpy9oSBsM3CsqC1oJQqUkr09oisETg8Ae4nRBgFNGDGLjGjglJQZRpvEij2AD1F9V357d 0iQ8GyyC44SPbyrhNzQBBa3u6v9F+FGdPIiTYJMTL9GawzmGTuD9yhr1+/MvGkZqE5J+Qsv3kTv HgCkwM77KanHS8LMjHRtXbGI4ZK5V4ZRmsQ5lgLkgov2dHD8ow0yl25GDNkUqXaHMbrNknzdipa IQfrcCO/oKFsPostd+Q9VrCG/iGG99q+lkXUryFywAt8b+e9ZbUdEjO2oRtgc+AGx07FPZ+NK9M BbwCG41KXRRtUop+nRrhR9YtM2Kk1VC86Dh4JW98GCw9sUopgPieD2IpzngPRraOjPH5argjKkJ uGTatD1K7304qoMhAQI+RL+Ji14iYjzyl3kdVt1F+QTE3VPqjDaAnLcCWbj9tjnJt7JbBwoy X-Authority-Analysis: v=2.4 cv=EtPSrTcA c=1 sm=1 tr=0 ts=686cd4b8 b=1 cx=c_pps a=qoll8+KPOyaMroiJ2sR5sw==:117 a=qoll8+KPOyaMroiJ2sR5sw==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=wKuvFiaSGQ0qltdbU6+NXLB8nM8=:19 a=Ol13hO9ccFRV9qXi2t6ftBPywas=:19 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=Wb1JkmetP80A:10 a=GoEa3M9JfhUA:10 a=VwQbUJbxAAAA:8 a=20KFwNOVAAAA:8 a=yPCof4ZbAAAA:8 a=gKLJ0jc5FbzXRXBV4SgA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 cc=ntf awl=host:12058 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 97AB3140006 X-Stat-Signature: bzhy95cguyuyt7siboyfa1mb94tggnyq X-Rspam-User: X-HE-Tag: 1751962821-781093 X-HE-Meta: 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 bKz/Su0T I2pqYF3iADrAtaIxrSckgqYSUb3DMTH0A8kwo6aHp95HEIWWWMPYBAts7eURwKUv9FWE/CeIqeT3twBmC1Hg6qPYVRCqeEkX8qqVWQEiIGUnHp17hz+zTVyovYsvVQFyQUky8Tp0owkFgu4ZbVmroNgzkL1tm5AEM5mZezyIHalU/Fhqxd3AcPBhFBUb9XtuSYKh1MwwcP0jtRWVToW0b1CdguLypBlNRrv0gLRq3FYA7CFzyJ8quM/W8SFyCRlc0tgUxg445nM04DZ/MN1ntkcSrfgT04Zu5o3AxB2kPAzhOEvg3Q688ZjDhW6wZLpne9qu0f8E74Ejx0yIL0tF2RT/xK4JUODx8sxMYRwUOvJU/p2TpGXr4QI0geYFdgcTvB6sMyrYCXMsgOLMqnwC0MyAQts0a+Xw9BZDxUFO4YFOimVvORRlgPaXNHVJPfUN0/A0eLSUnQAAbnZKhnqHCtH2gUy2t/NK3S+Ge6rr8OZfLJbQ/Qy1fl4OP9XF3qH3RP3NWr6dmJPGnu9g5m0CAy5/LNHtiqUhFu/TFVDYN5lRZIPSE5Et7fDeHyEqk6hvK0nBnTvOAEDbNcBugsi+An9WkLN+AZN7IgUBjQ0zFi3vJMOB3IyMurC1ozgOSmTxocipMCXoUMZQAKCSjcRRM6a+d7Y6QzlmV/2VKMdfsQsiL4Vh8nMT3hwZc1qMqfbrGpYhcoTEMUuSmzgqxO+6IOYvvp3t+xsan0lM44mVIXpsUPVkgSqtl4majivlAEzDF3rbuy4OwKl3JEi1HARolbc/ZPZX0z+sSzObjwbls5Hu3z0wzqpYBS210fqzjZRJtcGHbeEGWjTFTbCnGcMnE+z+LPWxwOXqj5JVt+96gq7gOcCYD6u/hQoi3boMlJk7Toqpg 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 Mon, Jul 07, 2025 at 11:40:55PM +0800, Barry Song wrote: > On Mon, Jul 7, 2025 at 1:40 PM Harry Yoo wrote: > > > > On Tue, Jul 01, 2025 at 10:31:00PM +0800, Lance Yang wrote: > > > From: Lance Yang > > > > > > As pointed out by David[1], the batched unmap logic in try_to_unmap_one() > > > may read past the end of a PTE table when a large folio's PTE mappings > > > are not fully contained within a single page table. > > > > > > While this scenario might be rare, an issue triggerable from userspace must > > > be fixed regardless of its likelihood. This patch fixes the out-of-bounds > > > access by refactoring the logic into a new helper, folio_unmap_pte_batch(). > > > > > > The new helper correctly calculates the safe batch size by capping the scan > > > at both the VMA and PMD boundaries. To simplify the code, it also supports > > > partial batching (i.e., any number of pages from 1 up to the calculated > > > safe maximum), as there is no strong reason to special-case for fully > > > mapped folios. > > > > > > [1] https://lore.kernel.org/linux-mm/a694398c-9f03-4737-81b9-7e49c857fcbe@redhat.com > > > > > > Cc: > > > Reported-by: David Hildenbrand > > > Closes: https://lore.kernel.org/linux-mm/a694398c-9f03-4737-81b9-7e49c857fcbe@redhat.com > > > Fixes: 354dffd29575 ("mm: support batched unmap for lazyfree large folios during reclamation") > > > Suggested-by: Barry Song > > > Acked-by: Barry Song > > > Reviewed-by: Lorenzo Stoakes > > > Acked-by: David Hildenbrand > > > Signed-off-by: Lance Yang > > > --- > > > > LGTM, > > Reviewed-by: Harry Yoo > > > > With a minor comment below. > > > > > diff --git a/mm/rmap.c b/mm/rmap.c > > > index fb63d9256f09..1320b88fab74 100644 > > > --- a/mm/rmap.c > > > +++ b/mm/rmap.c > > > @@ -2206,13 +2213,16 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, > > > hugetlb_remove_rmap(folio); > > > } else { > > > folio_remove_rmap_ptes(folio, subpage, nr_pages, vma); > > > - folio_ref_sub(folio, nr_pages - 1); > > > } > > > if (vma->vm_flags & VM_LOCKED) > > > mlock_drain_local(); > > > - folio_put(folio); > > > - /* We have already batched the entire folio */ > > > - if (nr_pages > 1) > > > + folio_put_refs(folio, nr_pages); > > > + > > > + /* > > > + * If we are sure that we batched the entire folio and cleared > > > + * all PTEs, we can just optimize and stop right here. > > > + */ > > > + if (nr_pages == folio_nr_pages(folio)) > > > goto walk_done; > > > > Just a minor comment. > > > > We should probably teachhttps://lore.kernel.org/linux-mm/5db6fb4c-079d-4237-80b3-637565457f39@redhat.com/() to skip nr_pages pages, > > or just rely on next_pte: do { ... } while (pte_none(ptep_get(pvmw->pte))) > > loop in page_vma_mapped_walk() to skip those ptes? > > > > Taking different paths depending on (nr_pages == folio_nr_pages(folio)) > > doesn't seem sensible. > > Hi Harry, Hi Lance and Barry. > I believe we've already had this discussion here: > https://lore.kernel.org/linux-mm/5db6fb4c-079d-4237-80b3-637565457f39@redhat.com/ > > My main point is that nr_pages = folio_nr_pages(folio) is the > typical/common case. > Also, modifying page_vma_mapped_walk() feels like a layering violation. Agreed. Perhaps it's not worth the trouble, nevermind :) The patch looks good to me as-is. -- Cheers, Harry / Hyeonggon