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 B5DC5C5B543 for ; Tue, 10 Jun 2025 05:50:29 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4E7EC6B0095; Tue, 10 Jun 2025 01:50:29 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4BED26B0096; Tue, 10 Jun 2025 01:50:29 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3AD7E6B0098; Tue, 10 Jun 2025 01:50:29 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 19CC76B0095 for ; Tue, 10 Jun 2025 01:50:29 -0400 (EDT) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id C6760BEABF for ; Tue, 10 Jun 2025 05:50:28 +0000 (UTC) X-FDA: 83538416136.25.27EDD3E Received: from NAM12-BN8-obe.outbound.protection.outlook.com (mail-bn8nam12on2048.outbound.protection.outlook.com [40.107.237.48]) by imf04.hostedemail.com (Postfix) with ESMTP id 0A94F40005 for ; Tue, 10 Jun 2025 05:50:25 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=jlol4ygI; spf=pass (imf04.hostedemail.com: domain of shivankg@amd.com designates 40.107.237.48 as permitted sender) smtp.mailfrom=shivankg@amd.com; dmarc=pass (policy=quarantine) header.from=amd.com; arc=pass ("microsoft.com:s=arcselector10001:i=1") ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1749534626; 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=Krc7Kf6WUz/ebnMlRZJ1SsbzShUeGasdzYoxkUxpwa8=; b=BL1kMZBD05Ny3lLKSLdNqYOUdw+GoVHFc21Y2/R9nCaOySo5XtJIw3YgQqqT2NnDyD/OuL kOFdFcbpofNuAkxI5m0wnxCgZPEZNd/GF58U/52HVJzoyZoCgVf9bqsHZ1DyyW1zsQ6cW+ FRQofL7qkF80lJj4P5/eX1DVvETzdlQ= ARC-Authentication-Results: i=2; imf04.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=jlol4ygI; spf=pass (imf04.hostedemail.com: domain of shivankg@amd.com designates 40.107.237.48 as permitted sender) smtp.mailfrom=shivankg@amd.com; dmarc=pass (policy=quarantine) header.from=amd.com; arc=pass ("microsoft.com:s=arcselector10001:i=1") ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1749534626; a=rsa-sha256; cv=pass; b=BG19WIseR9BsfRApIvIeHTBfVSEX457auT2mi2TMXvsNwCh0sUFP/nWfb4MJlKCqEMfONf cjbNRr9T8qviEqOjm+XJs4zNeJkwO4/7VPomCk5FLPCdKUPiAow0bBeG6nhdWNnBWRMAmO +wkRnpqH3EsahCqJ4B2ZNL8YEEydEJc= ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=DpKNL+BE30sepJXnuIUnwJqtSLwYj55CdGIv6rJI2yrCjbl1vDM10uOnbxYBzDcCsisoeRBVEDSYfqv2kI6/iDE/kbRd9xMgbwKdt9bAjyZL4xXQvfimPseX8O6n0zrXfHDb/4a00Lo5/TlJ8S5BtLm2d3T8GKWq4KSUw4HOLg9BTRVRAXjhw/BMuh8rPCGUZ9iK53F6gStofT7vTCsQeDNj+4D2weCrPjBOOnQmGh0vTzEgzkeWBb/y83PtoCzfsDzEY6ID3wJvlhF6JQucxkxJYqX2Qh2u7OI0OtHFoD5A0bZ1gTZyawPh9PgX+K22YGVI3Lj6oE9gX+pce3X84A== 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=Krc7Kf6WUz/ebnMlRZJ1SsbzShUeGasdzYoxkUxpwa8=; b=QcSIYio791d1ccV3K768lpIgwiK37INk12eXdCPMXvqmgwW0cuiq4+PZ4t1wbNcUFJYwkFzk701nMHjZWzSdbnqOFuLZXJ1dwE5Xcx6zFNoEIIbeAZo9P/N7LQ7YyfJFpQmAAK7/KkWlj0aAVn2gePKhuzssryBRO1C1UkHXapq79PrM6AMp3gFR6HKRNqYUSbgNG2bqsIBU63FNUYuDlI1oO0vzTlnTlMvKHy1U7aN7B5CorSeKdnIFvSsBMMn9TveUDBLhqojkffwutesKFcz5F41L6E5juEWYcAm4sAhcjmiPqCUFwOZSIDXhzW6fBsb/R3KWatgD1ohfRpQr4w== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; 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=Krc7Kf6WUz/ebnMlRZJ1SsbzShUeGasdzYoxkUxpwa8=; b=jlol4ygIuWGaJveAVFu3VtZ1NYZrGEyDwGD/Osim0QmmCRh5b0wfXGcnajeg00cISoaE83Cuz3cFmf8+YBk1Azza9fOyLsgv1Gdmil+4htU05q7FBrghyK0uJPXJ4PCI52LrFw8VVVm0QHt2f2K7XFX4TeXMtK4ir5ZLey0qNxc= Received: from CH2PR12MB4262.namprd12.prod.outlook.com (2603:10b6:610:af::8) by CY5PR12MB6432.namprd12.prod.outlook.com (2603:10b6:930:38::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8792.34; Tue, 10 Jun 2025 05:50:23 +0000 Received: from CH2PR12MB4262.namprd12.prod.outlook.com ([fe80::3bdb:bf3d:8bde:7870]) by CH2PR12MB4262.namprd12.prod.outlook.com ([fe80::3bdb:bf3d:8bde:7870%5]) with mapi id 15.20.8813.024; Tue, 10 Jun 2025 05:50:23 +0000 Message-ID: Date: Tue, 10 Jun 2025 11:20:14 +0530 User-Agent: Mozilla Thunderbird Subject: Re: [RFC] mm: use folio_expected_ref_count() helper for reference counting To: Alistair Popple Cc: mhiramat@kernel.org, oleg@redhat.com, peterz@infradead.org, mingo@redhat.com, acme@kernel.org, namhyung@kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, irogers@google.com, adrian.hunter@intel.com, kan.liang@linux.intel.com, david@redhat.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-mm@kvack.org References: <20250609170806.447302-2-shivankg@amd.com> Content-Language: en-US From: Shivank Garg In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: PN2PR01CA0067.INDPRD01.PROD.OUTLOOK.COM (2603:1096:c01:23::12) To CH2PR12MB4262.namprd12.prod.outlook.com (2603:10b6:610:af::8) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH2PR12MB4262:EE_|CY5PR12MB6432:EE_ X-MS-Office365-Filtering-Correlation-Id: fd3129a7-f44a-426f-2cc8-08dda7e2b096 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014|7416014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?WEg3cmpxZ2xscDNLMTBIRW9lQnVhcEdnY28zNm1aR1VzQk9jMis2RDJnZXA0?= =?utf-8?B?WnVrNWorUmRDVVdXbEF2NDg5aExhcDROOFQ2T3EyV3ZtZXJ5TExQMnZFUTNY?= =?utf-8?B?bXdKbzFIbllMT09PUlloM3pTTmk5MVZOZ012ZEJlVFJNNStjNkI0R0JleW5l?= =?utf-8?B?NmlvM2p2RmRYNTVLamRBaHB0ajlPT2hJOGdpYU9JTExReGU2ZUU0dngzVjFZ?= =?utf-8?B?OWh0a1ZLd1gveGRsS2tpTDNIcmt6bkV3Q2ZjWjVoM04xN1JvYXA4emwrSXpm?= =?utf-8?B?OFU5QzJDaU00NGFtTGJycXBQOGVHaDBqTzNQYmJndzFBT2xqOWROQWRkT2Jz?= =?utf-8?B?TDk3a2s4S2dlZTQwU2ZOODdkdjJZWlhsQXpMWGxCZUxtcnZXRVlEaE9HWDRs?= =?utf-8?B?S3JuRmxlWERTQVhyUXhRMjEvQUZUUi9DZU5vU0c4RnB0Z3NKaDh4NzZUL1hZ?= =?utf-8?B?Zk5yalJZOHgxSEkzQ01NZGxnZndQclJ4aWNqc1JvTEJiTHNMRjFJeVJMZkw0?= =?utf-8?B?OUNDUk5oUFlSOTMwK0YydTRDZzB3RHdLRXhMTUJNQ3dRMEJyWGxZR1JYRVJo?= =?utf-8?B?NEFiaklaSjVpcG9URHVTODZ6UjlkQ09MR2tqb095Y0VUQ3BFenY2dzlubzVQ?= =?utf-8?B?YmZsc0x2MlZ4ZlFiQmROSDhFZ0JZcExPL050V3lTNEF0a2d1OWUvMm5aQmFQ?= =?utf-8?B?R0UzcWZxMDZsblRuZHNPbjBZb2pxaGNTbnM1ZUhLakFFYk5GT1RqdHBBWWVH?= =?utf-8?B?djFNK3dENVFWT0lDUjIrM2c3akNaS09GNDhKQmFLUlJnYVJBSS9nd01ZWERE?= =?utf-8?B?M0lJMFVEckZQdk54Z2p1ZG80eTZ5SXB0aGFFTU5uYWhWaXR3dnVuRTlqMGdP?= =?utf-8?B?UVZwMVBTYVpoVHdzY1MwQUtHZGRGdjlRUHZmYzBXR3MrMStjblFEdld6RlJT?= =?utf-8?B?Qlg0OTF3QXBiRDhzZVdhNlY1ZHBzRG1OMHFxODlWNGlXM0dYQkE1VWhNV3JQ?= =?utf-8?B?eXdIZXpsMGFZcGNNUVl6Z2F5eDNkdC9UN2FDMzJqblFpdXo2Zy9sc1l3aCtE?= =?utf-8?B?Nk1kMVZDVWtMMEpsNjlqV3RCbkE0QlhGdVdYd0xEaXlzRUR2STV5MkxyMmpx?= =?utf-8?B?OFlxQlF1b29hdmo1c3FyWFZJb0htbTdlZGNtTzB1WVVLK29CTmtZR1NKaHM5?= =?utf-8?B?c0pEdEl6bTJGQ3JxSVd6a0lhL3UzdWFwdWh0WXVoM0hqNHZZWkszT28xd1pj?= =?utf-8?B?SFZsenVwK3FEbkRjcmtwZXZwdS9YQmwrbUNJUWpRUHAyMFVlMmhHSERROC9p?= =?utf-8?B?TWlJZ3k4TGE0Y0VBbVovcnFmVUVMZDFRTHpBR2F3ZmtaT2lrSDVhcEZoWVRV?= =?utf-8?B?ODVhTzhIcDJKelROYnFVMFpxTmdSQVdTdno4aEp0NHkyZEhZQk16YkdtdWxD?= =?utf-8?B?MkxPUTlmb1diVTZ2TVZtdUZ0eTA0VGFUcUlzRmhqbENFUFgyYUhRQk5ZU053?= =?utf-8?B?dlF0NVhBYldwU1RCNDVQS0lTaCtJeG5NYUFpQVl1dlFFQzFGWW41NERxalNY?= =?utf-8?B?STJMOW8wc1VpNlo4aTZhTEhHRnBucERTNUIyQ1BMVjhERUR2dXFjcGRSS1hv?= =?utf-8?B?OTBZTTV4T1pDRkwvdklSZHppT2wwaUNBTkcxbGRoMVBhbG12S3pWWGVJQmVm?= =?utf-8?B?SlU3WGZuZDhoZ1dwS2lYRE9uelE4ajBnTTZ2RGNXUVhsMXBCRGVVdmZnUHI2?= =?utf-8?B?ZHBXeEk0VkNDcWNzQ2prclpLdFRNQXdINHBPQ0ppNy9SQWVFN0t5anFMMjU0?= =?utf-8?B?cFprSCtmdVhNVFFnL2gwbE1LWWVPalpkSVRkdnIxdGk2ejB5b0J5N3ZVMHYv?= =?utf-8?B?NnVyQkhINCthdHd2eEtmNHZVQ0tteHdoMWp4bm1BdHNCZEdERzdjYjdCbUgv?= =?utf-8?Q?kGu2bn2r4pU=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH2PR12MB4262.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(376014)(7416014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?di9wL25MZEdSVUJJeXVZSTJrUURxQU5yRHVnOURXbDdGaUNZSmtUOW12Z2g4?= =?utf-8?B?NUVmZkRaYWlORDdqVEwzNXhCdEEyOVd5REdIbmhjTm4vbVdrMXFYWnlPK1lq?= =?utf-8?B?czR4UzMzb2d0SE5ZNi90S0c0NUJuNUJUeXNXcEZ4WXF1NmFDUzVHRWlPTTUv?= =?utf-8?B?MUtsTUEzWnRuclZVVXEvaWRmbG00akFsZVkyWnFwaGp5eDdTekVxTi9YTGVq?= =?utf-8?B?bkRYcVRMUzYrQ3BBUWpQRC9QaDBEYlg4QTJNdFJGRzVXMXRndlZhSGFEeWEx?= =?utf-8?B?V2JqeG9SNEtkMlpXRFZLQThta0pjaDQrYVg3Qk1uSlI2L0RWeW0ycDRCQlAy?= =?utf-8?B?SS9zWmJmd1MwaFlYc2pBeEpIODN0ZjNWdjhySXNmV1BvYm5vTzcrMmpVQURE?= =?utf-8?B?R1RkYUdsbU9yS0hCOEtydFd2a09xYmtOTzdtdmlENTRxblM3TUltU0s4bUtV?= =?utf-8?B?TzBQd1dCRDdQSVVqMGhEWnVKZE9xNUg3R3NUTktpQXFick1OSmNsYkJyTzIv?= =?utf-8?B?YUk1c3MvMlZUL0c1ZUZ3c2liU3Jmd3ZHK1luNFdIZHBsZjlWMVBzR3BTaWZP?= =?utf-8?B?WVRpVzRjNWF2cG5TdFB3WGFlT3lxaGxDSStXTVgvd3Q4QnF3bjZtTG1FZGdP?= =?utf-8?B?RDJNSUM0Tk9LdTNrM2F6RGZJWGQrenlJeThmSUdQTDR5VldKMDUrbEZiUWtv?= =?utf-8?B?QUd0eTd3ZktMR2NVZ2Q3ZEI2ekk2VUg5WnJhbXZPMTVGcEEveVhkWnpqdTZR?= =?utf-8?B?MXM0RWhpRUlJSGxGK1NwYVVFZ0NpV1JycDdOSTVSYmwyZVQvOHRGWHQzZDVE?= =?utf-8?B?aWVmWDFTbC9NUDZnNE5Ec0EwMXB5bXNNT3BZdkw3L0dHNEh6NFVvVDZBZnh6?= =?utf-8?B?QWU5K09DbFhNMUd1akF0cEh4VjdZYzRFYS8wU2FPZEJSS1FmY0FCblQ3T2VX?= =?utf-8?B?aURCOG5wa0ZwZGpUNlBNci9LbTdxdC8xbmx4ejcrMWxyU0RQRWw0VWdOTm1h?= =?utf-8?B?UkdHZjJ6MGR1bllJNEowa3VNTzY5eHVDb2tpa3VzR1V3V0E4THBQdGpsR1FK?= =?utf-8?B?V0l4aTlWY1ZXU2dPQWN6em53Z1BYWTZCMDJYN25jdW1lWm9FVlBEYnNVMlpu?= =?utf-8?B?cm9uSGJySnJDM1ptbWRRRlJLV3RTOHVSS01rZmQ2aTBHNXZtWHp2dExRQzRn?= =?utf-8?B?cTlId3ZKVGNjT0s4N21oczQ4SkcvZEcvK0Z2a0hMeTRDY1RSZ0NSSGNmTlFo?= =?utf-8?B?TWhJazhOU0lTUHMwRThsZFgyS1o1VFpxL2xYVGt0SllwSnpKNVRVS1pHdHZM?= =?utf-8?B?OHo0eDZWS1I2OGo1aU5xa3NUY2lHcHNaMmx3U0tlVm1GSjAzVnh6ZGQvN29Y?= =?utf-8?B?eWx4TFpTRm1FMEtid1FIeU0rdmwyU1AzeU9OaFNIVk10a1NobVI0SGFGY3cx?= =?utf-8?B?THJNZ3NtM0JPNFhvV3hXN2pBMWx5Ym5CaXhzcFI0dVMvQjFqNk42VEpyRnkw?= =?utf-8?B?RFVXSytCdTZudFZuSGZuZFJCNk5hc1U1Qm5BN3AyS3c1clVubDRCenlYTWx4?= =?utf-8?B?YlpXN0dJbEttbjRSZVc5eFhUSlo5ekJ4cDZ2SnUyWXRVcVU5RlUzU3daRVpJ?= =?utf-8?B?bExHZzluQUtTZCtOUE05eEl0ZmhxWUpiQVF2UHpYTW5OZEhKeUU1VGxWMDRv?= =?utf-8?B?ajlrdlRiTzFWakYwUTRXaXVITjJRSncxQVgxNnlEbGtZeUNZVjNmVEh3L3pL?= =?utf-8?B?c3dpSElUS2pYWjlVSTNEa1NhN1FvOXJtdkdNZnh1ancwNUh4cERNRHBMY1RV?= =?utf-8?B?YnhCZGdUcFhmdG5NVVJXUytKMUZlQVNNaE1NNW5veGd1cFFmWXZxY0xUdmlX?= =?utf-8?B?b3htTjZwVkdvVUE2VE1vTWNVRVczMndqRGwwcHM4cW9WcDJnZUVLMFVCY3Fx?= =?utf-8?B?b2dyNFI2Z28rWFo1Z1hBQVVHRFUxL2FtRitZZjErWmJJUnYwVzhQVnB1cDBp?= =?utf-8?B?dERXZ1JGQ0JacmJLaEF6dkdvenZQUW9taitWRDdXWTZxaGlVb0phSEFHczBp?= =?utf-8?B?ZTN2N1gxbURvaUJmWlNMdmQwWFVqdnhsallWa1d1dkJjQ3FDVEJ4TVJhSHJi?= =?utf-8?Q?cKc7aWquyOfVTbE8geM84u/Hj?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: fd3129a7-f44a-426f-2cc8-08dda7e2b096 X-MS-Exchange-CrossTenant-AuthSource: CH2PR12MB4262.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jun 2025 05:50:22.8488 (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: uwALNs8SA5LMaf5Cx5VjtsS+axAE5BO9mjmYaimaLSKTq9SxNJGulv4+qvOnf3Jr/Ww4DZtReul1ugB8/jN4fA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR12MB6432 X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 0A94F40005 X-Stat-Signature: w8tnq16zrtrydyu9f68dwawb6kbphk3j X-Rspam-User: X-HE-Tag: 1749534625-540117 X-HE-Meta: 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 nepP5Bzk 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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 6/10/2025 7:56 AM, Alistair Popple wrote: > On Mon, Jun 09, 2025 at 05:08:07PM +0000, Shivank Garg wrote: >> Replace open-coded folio reference count calculations with the >> folio_expected_ref_count() helper to improve code maintainability >> and reduce duplication. > > I wonder if there is any opportunity for reducing duplication more broadly? > The migration code has similar helpers (folio_expected_refs) as does > khugepaged (is_refcount_suitable) and vmscan (is_page_cache_freeable). The folio_expected_refs() and is_refcount_suitable() consolidation was recently merged: - 86ebd50224c0 ("mm: add folio_expected_ref_count() for reference count calculation") - 0b43b8bc8ef8 ("mm/khugepaged: clean up refcount check using folio_expected_ref_count()") > do_huge_pmd_wp_page() also has an open-coded version of these checks and there > are probably others around the place to. > > These could all be converted to a helper that returns all the "extra" references > after taking into account things like mapping, swapcache, etc. depending on folio.> >> No functional changes intended. >> >> Signed-off-by: Shivank Garg >> --- >> kernel/events/uprobes.c | 5 +++-- >> mm/memfd.c | 4 ++-- >> 2 files changed, 5 insertions(+), 4 deletions(-) >> >> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c >> index 4c965ba77f9f..c978c8c27340 100644 >> --- a/kernel/events/uprobes.c >> +++ b/kernel/events/uprobes.c >> @@ -434,10 +434,11 @@ static int __uprobe_write_opcode(struct vm_area_struct *vma, >> /* >> * When unregistering, we may only zap a PTE if uffd is disabled and >> * there are no unexpected folio references ... >> + * Expected refs: mappings + swapcache. >> + * We hold one additional reference (+1). >> */ >> if (is_register || userfaultfd_missing(vma) || >> - (folio_ref_count(folio) != folio_mapcount(folio) + 1 + >> - folio_test_swapcache(folio) * folio_nr_pages(folio))) >> + (folio_ref_count(folio) != folio_expected_ref_count(folio) + 1)) >> goto remap; >> >> /* >> diff --git a/mm/memfd.c b/mm/memfd.c >> index ab367e61553d..4ed5506221b7 100644 >> --- a/mm/memfd.c >> +++ b/mm/memfd.c >> @@ -32,8 +32,8 @@ >> >> static bool memfd_folio_has_extra_refs(struct folio *folio) >> { >> - return folio_ref_count(folio) - folio_mapcount(folio) != >> - folio_nr_pages(folio); >> + /* Expected refs: pagecache + mappings */ >> + return folio_ref_count(folio) != folio_expected_ref_count(folio); >> } >> >> static void memfd_tag_pins(struct xa_state *xas) >> -- >> 2.43.0 >> >>