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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B70DAD2D108 for ; Tue, 13 Jan 2026 14:04:21 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2BCAF6B008A; Tue, 13 Jan 2026 09:04:21 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 273776B008C; Tue, 13 Jan 2026 09:04:21 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0DFFD6B0092; Tue, 13 Jan 2026 09:04:21 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id ED3D56B008A for ; Tue, 13 Jan 2026 09:04:20 -0500 (EST) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id BF71116016E for ; Tue, 13 Jan 2026 14:04:20 +0000 (UTC) X-FDA: 84327110280.30.A314C83 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf17.hostedemail.com (Postfix) with ESMTP id 4D86240012 for ; Tue, 13 Jan 2026 14:04:17 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=OLlMk1yk; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=BFCHmSPr; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf17.hostedemail.com: domain of chuck.lever@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=chuck.lever@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=1768313057; 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=mP/g8UY32ndvOM3LKDx1ed8Dxn892wEzbwhdmJE7hTk=; b=szJJr5F6/X6jEKSKpaY3t72IDs9d6Kc6/v0bFe7+c0nIWre0ll2bsPf4ctMFG5SFnhRoxg 7h5zjSzOZHgx/jKdlJrYt7Ps9orcORQWnoC/va1fLS0R7s5w/imiS1g8Wdh1623InLgvjV qVvmM/T6i7Tr0KGceAT23xODxP2tLs0= ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1768313057; a=rsa-sha256; cv=pass; b=384ToinM7MJ0TtpinEhw8aUE4V3jBr7XJl1VaxMrQgs5ZKjs3Af0ATxWoTXUcJQwyHbyG7 +Oe/a2fuwrMroknKaxt2i99BJ2EXzFbdNUW8SjyE82oiLEzqF694WuKutneTcsbOQc8EWp 9CzkZPv/zoWothR9JWhJ6i9ABIyXGuw= ARC-Authentication-Results: i=2; imf17.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=OLlMk1yk; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=BFCHmSPr; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf17.hostedemail.com: domain of chuck.lever@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=chuck.lever@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 (8.18.1.11/8.18.1.11) with ESMTP id 60D1gZwC2395850; Tue, 13 Jan 2026 14:03:47 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=mP/g8UY32ndvOM3LKDx1ed8Dxn892wEzbwhdmJE7hTk=; b= OLlMk1ykanSrmUsKXyQJSp59G8drU7fTrANqMRkfkfDQhfIkSmo7xLmNiaeRX9ZQ PffYEXuKKjd4p8O4LgUEGYPvfUOXEP88/M8N6OaosL0faYlyex6PeOzHOYcelTbs g9nARv5pgj0bRNEWpl++TnJpmBd0bAnXtH2D1K01XdML4Fq+Kmo15sdXjyQa7a3Q L/Mp1EVuHc8hvxa/B36YJzruI5RV8ur0CCB6jmd5k3bJiz4WXBjU8EQwDrMheClE 5X2InQi9aeIlgisFYA9AekT9GJsty6LvGfwA8DFREGfSH8+aXdFm1+JeMilxOVS7 BSGAFzPWU17uxLflHV47RQ== Received: from phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta03.appoci.oracle.com [138.1.37.129]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 4bkqq53f06-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 13 Jan 2026 14:03:46 +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 60DDbCqo032777; Tue, 13 Jan 2026 14:03:46 GMT Received: from ch4pr04cu002.outbound.protection.outlook.com (mail-northcentralusazon11013009.outbound.protection.outlook.com [40.107.201.9]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 4bkd78s9mb-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 13 Jan 2026 14:03:46 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=waTBL9YNQ3eyQ1nK6upU4TFGAXXHkpC9jwzimvKa6AALpouovAQ8Wi2/47JQ5Z3oc/cVEZJN77q6wdBvLY5XFN4j8RWKua59PnZhxccHyeRNXU8bfXCkKA3BV+Ovw603BP5zXo2NlCHt5viz4BmNVqD8kUCJq3NFiBHhB583fz5i0ZSae7zzYpidlwkJvWWbb4nPXFro0AOrOHRvYrrr/6aZWq2FQdGoIZo8V+11H7R2gd+/WiaiHpXoTSeILN54FMxbrg9xfGkIrnANhS8lIFMJickQbpZqImD2vc4W43z3tyyX6l0Zmqi88VnvDd3RlF7UgwBXmWo9kcxEOGMX7Q== 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=mP/g8UY32ndvOM3LKDx1ed8Dxn892wEzbwhdmJE7hTk=; b=Hl4QjcFzGPURq4sEALrKTX8hDKNCA3lxQUfU4LTBE/cJrV1If/dM+UQiCci+EOsM/uKpqUXaGy2INtxca4kAo0oWa4XVAAmCyDG/Wv5AaRQ2Ibmvv6hKHv0pe7l23PfFrrPkJ7hk/jrVMdwLZBIpefVhgpA4iijQfo/8aziCs3pRbfWwRE5c8o7YBSvFzghtikIRJ5wusTfGlGVCEKS7P8yuc23OczN/Bomqxx4DqBXvzAd6k5zy5sgJLXXyvt5Cm/I+aqNAOi5Ws6KErlQH05MfYE7JBOcuThqgXV6ubev4/dAa8PbCJruDz3Vv4+apypER6M5w2l0oomP4RSnS4w== 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=mP/g8UY32ndvOM3LKDx1ed8Dxn892wEzbwhdmJE7hTk=; b=BFCHmSPrNHFT/TaKzFSDYxSRsAPzOvCCBQeZz915ecABFjMZfc4QPF9nKpwxYMFTZ+rCiVhWysGCIxbV90QNcZYB3Yro9OYEK7UyAVp+ZfT3S1AGS0HkIUn5cJzNuHmjxvgppljl21iO2iZoyuFx836xGTQ2pxTAHofb9HZLvBc= Received: from BN0PR10MB5128.namprd10.prod.outlook.com (2603:10b6:408:117::24) by CY5PR10MB6120.namprd10.prod.outlook.com (2603:10b6:930:34::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9499.7; Tue, 13 Jan 2026 14:03:40 +0000 Received: from BN0PR10MB5128.namprd10.prod.outlook.com ([fe80::4083:91ab:47a4:f244]) by BN0PR10MB5128.namprd10.prod.outlook.com ([fe80::4083:91ab:47a4:f244%4]) with mapi id 15.20.9499.005; Tue, 13 Jan 2026 14:03:39 +0000 Message-ID: <5809690c-bc87-4e66-9604-3f3ee58e2902@oracle.com> Date: Tue, 13 Jan 2026 09:03:27 -0500 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 00/24] vfs: require filesystems to explicitly opt-in to lease support To: Jeff Layton , Christian Brauner , Amir Goldstein Cc: Jan Kara , Luis de Bethencourt , Salah Triki , Nicolas Pitre , Christoph Hellwig , Anders Larsen , Alexander Viro , David Sterba , Chris Mason , Gao Xiang , Chao Yu , Yue Hu , Jeffle Xu , Sandeep Dhavale , Hongbo Li , Chunhai Guo , Jan Kara , Theodore Ts'o , Andreas Dilger , Jaegeuk Kim , OGAWA Hirofumi , David Woodhouse , Richard Weinberger , Dave Kleikamp , Ryusuke Konishi , Viacheslav Dubeyko , Konstantin Komarov , Mark Fasheh , Joel Becker , Joseph Qi , Mike Marshall , Martin Brandenburg , Miklos Szeredi , Phillip Lougher , Carlos Maiolino , Hugh Dickins , Baolin Wang , Andrew Morton , Namjae Jeon , Sungjong Seo , Yuezhang Mo , Alexander Aring , Andreas Gruenbacher , Jonathan Corbet , "Matthew Wilcox (Oracle)" , Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , Christian Schoenebeck , Xiubo Li , Ilya Dryomov , Trond Myklebust , Anna Schumaker , Steve French , Paulo Alcantara , Ronnie Sahlberg , Shyam Prasad N , Tom Talpey , Bharath SM , Hans de Goede , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mtd@lists.infradead.org, jfs-discussion@lists.sourceforge.net, linux-nilfs@vger.kernel.org, ntfs3@lists.linux.dev, ocfs2-devel@lists.linux.dev, devel@lists.orangefs.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, gfs2@lists.linux.dev, linux-doc@vger.kernel.org, v9fs@lists.linux.dev, ceph-devel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org References: <20260108-setlease-6-20-v1-0-ea4dec9b67fa@kernel.org> <8af369636c32b868f83669c49aea708ca3b894ac.camel@kernel.org> <20260113-mondlicht-raven-82fc4eb70e9d@brauner> <4a38de737a64e9b32092ea1f8a25a61b33705034.camel@kernel.org> From: Chuck Lever Content-Language: en-US In-Reply-To: <4a38de737a64e9b32092ea1f8a25a61b33705034.camel@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: CH5P222CA0014.NAMP222.PROD.OUTLOOK.COM (2603:10b6:610:1ee::6) To BN0PR10MB5128.namprd10.prod.outlook.com (2603:10b6:408:117::24) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BN0PR10MB5128:EE_|CY5PR10MB6120:EE_ X-MS-Office365-Filtering-Correlation-Id: 0ec1a10f-0ee9-4e4d-92fe-08de52ac8d81 X-LD-Processed: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|376014|7416014|366016|3122999018|7053199007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?dUpMV2doUnZNU1BJdVpLTm5aRVAvUUVEUCszdTVXNEYzYTRMYy9ISHF3L1Ix?= =?utf-8?B?bDloaU4yai9aR0txMlVVOUxpSlRIOXd1TWt1Y1dPUFJTS295Tm1WR1UzbGFM?= =?utf-8?B?c3RzSTY5bTE1dmNzMXRrenQvYytFVllkOWhKalM3TS9HZ0tCNUNtVDdyTFNh?= =?utf-8?B?b0Fjb3d2R2VPbEVmUWdoMSsveTYvcDMzelFqbDlYSnFIM1NRTHQwOEdaeUdu?= =?utf-8?B?MlhDRUlMRUtBM0tXa2lxcHZ1OGYvMXdMTHpNZGhCdk1QOWMzaitkSDUvcnE2?= =?utf-8?B?Qkp6eVlZemd0aVhtTmZ5czFNN1Yyb2xKL2R4TjlvSVhVblhRa3hXaXB2b0h5?= =?utf-8?B?Z3NpZXBrWjFVNy9tRXZVbVVscHVKdjBDaWxJVW1MSkErcS9TVXd6ZHh1aXVT?= =?utf-8?B?dEg0Ni9IL1MrcG1MVStGbExwTW1EYksrcW1vQUtFQWd4RmFtaTliK3RscFpw?= =?utf-8?B?dGNJcHJrSnlGUDhGRmU3cTVEZWF4S3NFVFpaSmkyVlFWSHRPa3V2OEF4VmtR?= =?utf-8?B?SDZKVlg1bk5aZ3BOemYzWGwzODVlb1NNVkptM1NYd085TVNqNWNnVGFKQ3hH?= =?utf-8?B?ejZhQmp0OE52TVFDblYxNVV3WVNOM1hVTnVMcjZzRHhGM2JhcThzY2NPNmpu?= =?utf-8?B?byt5VnRPWk1PNVZ0elh0Qzd3aitQYkRPNkg4YjBsT0ZYZER3ZjY0UGkwVW1R?= =?utf-8?B?NmdMSFFWVFpEdHlIOHNzTjhtcFlJL2ZDby91dlJ1dU1sWmZjV3BtT2JkMVhi?= =?utf-8?B?cnlidG5VRWpFWTlGN0dLSmduRkY1KzNYeUFSdUVCK0N3OXpYcGthL1BmaDdp?= =?utf-8?B?QkplcTcwdEhRQlAydkhIaFNidFBFR1UxNVE4dEREYkRGeFRDOHNBM0grWGIy?= =?utf-8?B?bjZPOVk3RDhveTRoMzlYRHBobURQVVVGdHhYT3J4K0pLUEtVeGxmY21jeVFR?= =?utf-8?B?Q0xpajRUbFZtaFdTZnVwME9OTU5QNVZFUkh3eHU1d3VwZlV6YjUzOHRGYVhh?= =?utf-8?B?blZCdUhXN3Q5U1lnVUxUWmpRZFhQaFZsSXJlVXhwTVJDOW9yaDUrSEUxY0Iv?= =?utf-8?B?Z256Um1lS2ZWdWZlWGRLcU0rNEFPaXVIMXh0QWlDczBjdjNObnFDcDFjZmFM?= =?utf-8?B?clM2b0thNTgzT2N1UmxhU3lDUXlzN2FkTHVUWVFRdkFBcUV1TjNlWGU1Wktr?= =?utf-8?B?RnJGS3hHOGMxVmpYaWJhWTF1QTNkeVVMMFdvZ2E5aUJSZVFxV3lXWHFlS0Nz?= =?utf-8?B?emVZZE41ZER6bVBZdUE4di91dmoyVmpxajQrU3ZPQkN2ZmcyRmh4UnVpUmlC?= =?utf-8?B?anliZnFzQ1RGREpzZjFGL1RJQ29sOGc4T0FXY3F4dlBaUi8rZTdQckprUTJ5?= =?utf-8?B?ZUIvK3lDZGh5dVNxYlpSejgwZXlqSEs3WVU5QTY0bjlkQjdvZ0o3Z25ZaDN2?= =?utf-8?B?SjdMSTl4ZHZ0WHdCN1Fja1dVZXU1SDVrTndrYUF4VFNHWUNXWnduL3c5ai9N?= =?utf-8?B?MTJzUkJ5cWZUSWkyUDRnUWZ2cVgvWWl3Rm0vaFVkMW1wVlZGbjREaW03WU9O?= =?utf-8?B?Qk1ibUhnMVRIQ3JROWZiRVhxekxIZG9FQktoOWFmRm5pUFZGUGVId21ZYWNO?= =?utf-8?B?TGpmNlowK002UksxRnNsb2xtb2F3UGZ1V3JWeUp5c0J0a01ITC9JRzRPbnIr?= =?utf-8?B?bkVsTzJteWhOM3ZOVC9HNEowajVXaGxTcGI1N0FoYWRWOTBVMEttR1hldHI0?= =?utf-8?B?NjFaMXJPTytsZFp0ME8xUlZaRmNvWG1Wa0p1WFVES3VoYmk5U0JPVXJXREha?= =?utf-8?B?MllId0Q2UkVCL3FENWk5UXFUNVlZdXQ2Y1piQmlJNDB3WXJsakZCZUtQOXdB?= =?utf-8?B?MmRLeWVvSHI2eVpGZzNYTm53enNhdzYyaHlhZ01LS0NKNndZKzlsRCtwbG91?= =?utf-8?Q?DzC7P+c324FkCWCbqJ0EqFBj3M/1Lt+H?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BN0PR10MB5128.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(376014)(7416014)(366016)(3122999018)(7053199007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?VU5LWGVwYUgzckRwZG9yeHZxVEd3WFFvZmp6WDd1T0NxNEhzSGhjd25MckZP?= =?utf-8?B?M1FqMEQrVXNMaXQyQ05aK0lXY0xEbUtLN1dKeTdZMVdrYVI1M3VicWdudGI3?= =?utf-8?B?MG0vV2R0VEpSM0ZINDBRTHZOVGk2NHNLd01GQ3QrejJYcWd5S25kaDN4L3dx?= =?utf-8?B?UC8ra1hJV216aVdpTjl3T1Qya0xoRFRreXJwVDU4Nnc2dTR5a0M4SmRFSHRN?= =?utf-8?B?WHlhbnJJMU9mRGlyNHBKNzhhaGYxR1E3SFh0MlU5SlhZSmRLWFFhV3djMTNj?= =?utf-8?B?SHRPZWpOUWtzNUk1OUNXMGx5cElKazdRZzExZ2NLUWIybklxVk1Yd2Jibzh5?= =?utf-8?B?NCs5SkVESGNWWTVxUm9sNmQ1dVdBaGsxRkdIcERwdDRoTUJvMWhIalVwUWUx?= =?utf-8?B?ZjJVOXpKeWJidVlPbUxJNU8yMUFhN0d0a1ZFSWt2dk9WYXlyMWowN2k3aDQw?= =?utf-8?B?N3pKN3ZZOWV1SlhCYlFPanQ4bzdyb1NqL0RkRWNTSkdrTzFYOFAyaUN2WXdi?= =?utf-8?B?TWRGTGw3KzBGNlg1OHFoUVkwbXpJV2d1VlNDVmdQVjM4dFNoSmRTcnFRcEpB?= =?utf-8?B?VmU1bklKd0NxRklxWUd3ZHJ2TzhrSWxIdit6WTZUNWVxQjIrVG0vN2Rkbmxv?= =?utf-8?B?dEM3N3dtN0EvNU9IU3dUWHNoUnVwYmE2U2hieWZaVzJMV1ZGZ0FNekJhRDFl?= =?utf-8?B?UFV4TjVVUmFjMWthTEhZdUkxai9reGhxWmhWRDczSnFsc2pPbEhVVVVoMURG?= =?utf-8?B?dVBhb05wbmpaS2hndStVZkJlWHNhRStlV0JVOUUxN0xleE9ZQVNMOHlpVzly?= =?utf-8?B?Q1k2Y1ptL0pYaG11WXFpaDZiWWlLdGZPT2tQeHRIVEJwUHFndE9LT2gvWDVw?= =?utf-8?B?M1NmMUhMQlcrb1VVVDZmcVdScEJhMm5YUmZLRGh1elg4a21kcmlJeUx1SGhv?= =?utf-8?B?U1E2aDVBZTM5VUo1dndMNHUwOFVJOVF5b0k2empDT3d1YjkyZ09ScXpydk9j?= =?utf-8?B?ZEVrbndYbjBkNkx0SGc3Z013RGpqR3BUbThmL2h0UmNnZDZDMVlxVnBtRUFu?= =?utf-8?B?TGxNbHkvNTRqTnJvS3IzRm14aEdDNmNIMUxYeUdValh0eTJySUF6eWl2bmhH?= =?utf-8?B?Q3ZMQ1duUTBqZGhSUnpsejZ5bk53NkNaYnlZUi81VUtmV3VCTkFBSTJ6SVFW?= =?utf-8?B?Wll4WjBWWEdFWEJDMHFNSHRBNHAwY0MvNkwzdnlOa29OUG5pY3lyeDV0UCty?= =?utf-8?B?MUl4WDFqc0NqdE1Gd2FjSW13QUUwMXNvaTN3NmY0SnhiYkcwd3E1UythaWdU?= =?utf-8?B?dnQwWFFseEd6OWhsRHdMRmQ3T2Qyek1JT3hSUGxOMHo0QWZTK2tnVjJZYTk4?= =?utf-8?B?NUkrQU1iSkRuYWprRnNOR0REOWdrNm9RaGk3OWdzT0o3L1ZDejdIZ1BBbnFD?= =?utf-8?B?NEMwN1dsVnVKcWxyREt2LzlWU045Z0JvR3lZbUVpMXVtZkpjem5nSHVON2hZ?= =?utf-8?B?VmE4T2lORzZXaUg4OVN3Z0VFMEQ0MURGMU14bzFPSnNUTFNxeDE1amNBb0pW?= =?utf-8?B?Z1pwdWZNbjFGWVdQTHVPbXdUYUw3Qm9WVHhVNDg0Z1JFMmtmeXE5SThIYzhs?= =?utf-8?B?dUFtMGFGV0JtemlBUmFENjRvN3pFWjNhQWNOcGlSa3p1a2N4anVBRlpiUmJH?= =?utf-8?B?VnFscjk0OCtjZUx2elRlaXFNa3BHdUNQT0thczBkWGExTmJCdXFQaU1YMnJP?= =?utf-8?B?WTQrNzVJNGpESVBDQ1FkTHRxY1B6dW9JdG5oek5FSzYzQ3ptYVlCT2p5ejBi?= =?utf-8?B?dW1hcnM2V3p5OW9CMW9LeC9PbitXWEwyd24wdVkwR05ZeUZKcm8yeWJjQ0Nv?= =?utf-8?B?cFdQOUdpb0Y0bDlsTHBXMG1nbVI4ek1BQXZJKzl5RmUwazdCWUVpTS9CajZL?= =?utf-8?B?V3hLZFBIUkc1bTJadUNZVytUa0o5QVU3bnBWNzRrVnVnNDAxQ0t0anF6UEda?= =?utf-8?B?Mjg5ODBSRnFFR3V0TFYveGlLYzZEa1ZYVXFFeDdsK3Z5c1MvbHFqdlh2RmFH?= =?utf-8?B?bTZPc0JmLy83aGl2TG8rM2lIdnlySkl1ZXV2dzdFN2RTWXd6VFZlTGRMVEtW?= =?utf-8?B?NDdtenBKY3MwUHhqK292WTdVaTNia1VGais5NTQxay8wZENCWlJNQnkwUHNz?= =?utf-8?B?eG8zQjNXWEIyMVRpS01DMmdYTUJBTFljdXhRRHY4aFVYeXhkQjNuQUFqVnQ3?= =?utf-8?B?VnVNYWlac0RXdlFQdzFjWC81dXF1YzlucTFzYkNPSHI1V2IrRTJqZTNrOFNm?= =?utf-8?B?MjRvOWc4eTRTdVFiKzd2MU9PSjBZNkRJZGU0UVl1VTVUM1dnNHNidz09?= 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: 0ec1a10f-0ee9-4e4d-92fe-08de52ac8d81 X-MS-Exchange-CrossTenant-AuthSource: BN0PR10MB5128.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jan 2026 14:03:39.6750 (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: YGk2SXNN0FjDKmDnetA74beY9FS4bgv486Upczd4bUxd2faLluaNpjzaaTsnfE0+2g+Wax5DOjfhNiPF7L+bpA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR10MB6120 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2026-01-13_03,2026-01-09_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 mlxscore=0 suspectscore=0 mlxlogscore=999 bulkscore=0 malwarescore=0 phishscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2512120000 definitions=main-2601130118 X-Proofpoint-ORIG-GUID: 2YNEE3Tr-BYkU9W3QqbyBTutfIfueKeK X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTEzMDExOCBTYWx0ZWRfX3JSZYS9RlbVF idO5zgTdYUc7eGw2FuOzKzZL7T+NIHez4Y1TabBnRpp2YVb/fDbkNIGLFJ45GRip2J0k0vRT9m7 s1CJzn/Ry0vIjQMoHEc6I9/vWHCMJgokJzMNaTOi4NRXvVR/h4LaRbXf7UwgWEArR7PaYx+GoO/ +jkuYrruMZWUnXxnyHmXlKcR3xIlzs4QERX8FvGIitIY3F4OUPV2EA3JfX6+CpEocEPXmYVclTk Rs1TEsf27OQglg2T7gHMu5mqfGYEs1vmXjZe5u2xaDERL2j96y5h0cCI3dMLDGXo69P/dp3NTkl V2SwuR5oQfClJp/3V52e89tcjJV1cw+4JLE2zhFwHGBlRdUyF6U/daKbKOFFb/A91PY7FckOeXE tlK4w5Xpn+o21oRyrHkWYSzSpn/vCully62OLr8Oyp3x44P1Ba4lYZuzVsICjiUtivZpUGNm8rQ SwlHWOMmOT1LpJMtHKQ== X-Authority-Analysis: v=2.4 cv=J9KnLQnS c=1 sm=1 tr=0 ts=696650c2 b=1 cx=c_pps a=WeWmnZmh0fydH62SvGsd2A==:117 a=WeWmnZmh0fydH62SvGsd2A==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=vUbySO9Y5rIA:10 a=GoEa3M9JfhUA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VwQbUJbxAAAA:8 a=Y791ZhcX_UeUQF-99ecA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: 2YNEE3Tr-BYkU9W3QqbyBTutfIfueKeK X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 4D86240012 X-Rspam-User: X-Stat-Signature: pjgo8hke848t1n8e5uje39ii8q1rx54z X-HE-Tag: 1768313057-673634 X-HE-Meta: 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 GD6Dw0fo pAza5US2NVnU6YLBKnowgfo2bbqYO5+yqKXJYCQhcaw56W8yhSL8yaRCabz9HwtYjERDmJpKG/OKrU3v4LoVpQ8+p76MHaFlgtP5B3vm1CwzN3JzoBnI7SEd4SQIIrGfspZjFVGsG8CjoL0gpunwNH91ldb91PS+jIZfM 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 1/13/26 6:45 AM, Jeff Layton wrote: > On Tue, 2026-01-13 at 09:54 +0100, Christian Brauner wrote: >> On Mon, Jan 12, 2026 at 09:50:20AM -0500, Jeff Layton wrote: >>> On Mon, 2026-01-12 at 09:31 -0500, Chuck Lever wrote: >>>> On 1/12/26 8:34 AM, Jeff Layton wrote: >>>>> On Fri, 2026-01-09 at 19:52 +0100, Amir Goldstein wrote: >>>>>> On Thu, Jan 8, 2026 at 7:57 PM Jeff Layton wrote: >>>>>>> >>>>>>> On Thu, 2026-01-08 at 18:40 +0100, Jan Kara wrote: >>>>>>>> On Thu 08-01-26 12:12:55, Jeff Layton wrote: >>>>>>>>> Yesterday, I sent patches to fix how directory delegation support is >>>>>>>>> handled on filesystems where the should be disabled [1]. That set is >>>>>>>>> appropriate for v6.19. For v7.0, I want to make lease support be more >>>>>>>>> opt-in, rather than opt-out: >>>>>>>>> >>>>>>>>> For historical reasons, when ->setlease() file_operation is set to NULL, >>>>>>>>> the default is to use the kernel-internal lease implementation. This >>>>>>>>> means that if you want to disable them, you need to explicitly set the >>>>>>>>> ->setlease() file_operation to simple_nosetlease() or the equivalent. >>>>>>>>> >>>>>>>>> This has caused a number of problems over the years as some filesystems >>>>>>>>> have inadvertantly allowed leases to be acquired simply by having left >>>>>>>>> it set to NULL. It would be better if filesystems had to opt-in to lease >>>>>>>>> support, particularly with the advent of directory delegations. >>>>>>>>> >>>>>>>>> This series has sets the ->setlease() operation in a pile of existing >>>>>>>>> local filesystems to generic_setlease() and then changes >>>>>>>>> kernel_setlease() to return -EINVAL when the setlease() operation is not >>>>>>>>> set. >>>>>>>>> >>>>>>>>> With this change, new filesystems will need to explicitly set the >>>>>>>>> ->setlease() operations in order to provide lease and delegation >>>>>>>>> support. >>>>>>>>> >>>>>>>>> I mainly focused on filesystems that are NFS exportable, since NFS and >>>>>>>>> SMB are the main users of file leases, and they tend to end up exporting >>>>>>>>> the same filesystem types. Let me know if I've missed any. >>>>>>>> >>>>>>>> So, what about kernfs and fuse? They seem to be exportable and don't have >>>>>>>> .setlease set... >>>>>>>> >>>>>>> >>>>>>> Yes, FUSE needs this too. I'll add a patch for that. >>>>>>> >>>>>>> As far as kernfs goes: AIUI, that's basically what sysfs and resctrl >>>>>>> are built on. Do we really expect people to set leases there? >>>>>>> >>>>>>> I guess it's technically a regression since you could set them on those >>>>>>> sorts of files earlier, but people don't usually export kernfs based >>>>>>> filesystems via NFS or SMB, and that seems like something that could be >>>>>>> used to make mischief. >>>>>>> >>>>>>> AFAICT, kernfs_export_ops is mostly to support open_by_handle_at(). See >>>>>>> commit aa8188253474 ("kernfs: add exportfs operations"). >>>>>>> >>>>>>> One idea: we could add a wrapper around generic_setlease() for >>>>>>> filesystems like this that will do a WARN_ONCE() and then call >>>>>>> generic_setlease(). That would keep leases working on them but we might >>>>>>> get some reports that would tell us who's setting leases on these files >>>>>>> and why. >>>>>> >>>>>> IMO, you are being too cautious, but whatever. >>>>>> >>>>>> It is not accurate that kernfs filesystems are NFS exportable in general. >>>>>> Only cgroupfs has KERNFS_ROOT_SUPPORT_EXPORTOP. >>>>>> >>>>>> If any application is using leases on cgroup files, it must be some >>>>>> very advanced runtime (i.e. systemd), so we should know about the >>>>>> regression sooner rather than later. >>>>>> >>>>> >>>>> I think so too. For now, I think I'll not bother with the WARN_ONCE(). >>>>> Let's just leave kernfs out of the set until someone presents a real >>>>> use-case. >>>>> >>>>>> There are also the recently added nsfs and pidfs export_operations. >>>>>> >>>>>> I have a recollection about wanting to be explicit about not allowing >>>>>> those to be exportable to NFS (nsfs specifically), but I can't see where >>>>>> and if that restriction was done. >>>>>> >>>>>> Christian? Do you remember? >>>>>> >>>>> >>>>> (cc'ing Chuck) >>>>> >>>>> FWIW, you can currently export and mount /sys/fs/cgroup via NFS. The >>>>> directory doesn't show up when you try to get to it via NFSv4, but you >>>>> can mount it using v3 and READDIR works. The files are all empty when >>>>> you try to read them. I didn't try to do any writes. >>>>> >>>>> Should we add a mechanism to prevent exporting these sorts of >>>>> filesystems? >>>>> >>>>> Even better would be to make nfsd exporting explicitly opt-in. What if >>>>> we were to add a EXPORT_OP_NFSD flag that explicitly allows filesystems >>>>> to opt-in to NFS exporting, and check for that in __fh_verify()? We'd >>>>> have to add it to a bunch of existing filesystems, but that's fairly >>>>> simple to do with an LLM. >>>> >>>> What's the active harm in exporting /sys/fs/cgroup ? It has to be done >>>> explicitly via /etc/exports, so this is under the NFS server admin's >>>> control. Is it an attack surface? >>>> >>> >>> Potentially? >>> >>> I don't see any active harm with exporting cgroupfs. It doesn't work >>> right via nfsd, but it's not crashing the box or anything. >>> >>> At one time, those were only defined by filesystems that wanted to >>> allow NFS export. Now we've grown them on filesystems that just want to >>> provide filehandles for open_by_handle_at() and the like. nfsd doesn't >>> care though: if the fs has export operations, it'll happily use them. >>> >>> Having an explicit "I want to allow nfsd" flag see ms like it might >>> save us some headaches in the future when other filesystems add export >>> ops for this sort of filehandle use. >> >> So we are re-hashing a discussion we had a few months ago (Amir was >> involved at least). >> > > Yep, I was lurking on it, but didn't have a lot of input at the time. > >> I don't think we want to expose cgroupfs via NFS that's super weird. >> It's like remote partial resource management and it would be very >> strange if a remote process suddenly would be able to move things around >> in the cgroup tree. So I would prefer to not do this. >> >> So my preference would be to really sever file handles from the export >> mechanism so that we can allow stuff like pidfs and nsfs and cgroupfs to >> use file handles via name_to_handle_at() and open_by_handle_at() without >> making them exportable. > > Agreed. I think we want to make NFS export be a deliberate opt-in > decision that filesystem developers make. No objection, what about ksmbd, AFS, or Ceph? > How we do that is up for > debate, of course. > > An export ops flag would be fairly simple to implement, but it sounds > like you're thinking that we should split some export_operations into > struct file_handle_operations and then add a pointer for that to > super_block (and maybe to export_operations too)? > > This would be a good LSF/MM topic, but I'm hoping we can come to a > consensus before then. > -- Chuck Lever