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 C25E2D3C523 for ; Thu, 17 Oct 2024 16:47:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EA7EF6B007B; Thu, 17 Oct 2024 12:47:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E57E36B0082; Thu, 17 Oct 2024 12:47:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CD1996B0083; Thu, 17 Oct 2024 12:47:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id AD8276B007B for ; Thu, 17 Oct 2024 12:47:23 -0400 (EDT) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id A2B6914144E for ; Thu, 17 Oct 2024 16:47:11 +0000 (UTC) X-FDA: 82683674640.29.4FBEF5D Received: from NAM10-BN7-obe.outbound.protection.outlook.com (mail-bn7nam10on2075.outbound.protection.outlook.com [40.107.92.75]) by imf08.hostedemail.com (Postfix) with ESMTP id 90894160016 for ; Thu, 17 Oct 2024 16:47:13 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=Nvidia.com header.s=selector2 header.b=UO4RQZBt; dmarc=pass (policy=reject) header.from=nvidia.com; spf=pass (imf08.hostedemail.com: domain of jgg@nvidia.com designates 40.107.92.75 as permitted sender) smtp.mailfrom=jgg@nvidia.com; arc=pass ("microsoft.com:s=arcselector10001:i=1") ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1729183592; a=rsa-sha256; cv=pass; b=WdzjW0rdY86GN7adrgmrMqgBe6xirEA3PV+fQK26uRmjFAAivi1Uk+WrU2eujtJpk/WAH7 gPzOkUuOivDJHJjmsEQ1b0QR3rrlBm2FnwMhlc0pM5Hqh16QizYTCq7q4IDqOdE7IZgx8X 7GB6QyqL0UTddLqE9a/E+43XiEpY1NM= ARC-Authentication-Results: i=2; imf08.hostedemail.com; dkim=pass header.d=Nvidia.com header.s=selector2 header.b=UO4RQZBt; dmarc=pass (policy=reject) header.from=nvidia.com; spf=pass (imf08.hostedemail.com: domain of jgg@nvidia.com designates 40.107.92.75 as permitted sender) smtp.mailfrom=jgg@nvidia.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=1729183592; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=tszIbXkBraTqGp29c7/7twATeW0D90xuu5uPIEBuM9k=; b=oCt61lYaU+KDEe60A16Em1mmuAajqhJXOQ+pOcHL1B4nnw66gPQwl71QTpkcTKPrHsyWk6 KgCpkVKMsH8YV+OpUHWZJ2PtCpO/YsFpcZICtf1sPcqxXTWIrI9VXZz2Pco7McO7qq2Nlr UfL3mr5rLJvQnquGm4Mk8NTAwiFGYxs= ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=J126fekHRcpoJzh3m4AsyiwYBwYhRgwQO3Emmj42SSXcWNlYoKsq3iyEVs32YZvDD4ZfBOOnMgtOP2D+9VkYW9oOYvG8zX4DP+NOv9VbOXCDCPYji+eRax1A2jVAssEuuFWl/fUDDb88oPtWR6THhbwXAH9D76egaEbC4ZLZk6AHQ0MQ4KG1f4+J7sGJS9m0yfu5TgQOEokiYyo2ZDA4GD7DAiS6TrqsMYDMas+rJlMr9Lq6rb1bDTkgDSWyI/I3MybFZGymJOU7lOKuMRBTFMfYjRdksWMm777VBpsLm7W6VUuVksiS6RQm5+sPIL9pSce+2Cs43nfrOErpnsCUdw== 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=tszIbXkBraTqGp29c7/7twATeW0D90xuu5uPIEBuM9k=; b=vHK1aD9GcDYEbRYhUHIUFpYq6P2Pmi3EqQjOHYgG/k3NlU19vcaJokXt1fCsoDYjAH0/OO2wIj6kTVbLwh9YpIs5o1r7Wf56aMDLDnDbsBDYt2rBRF+TzmnnW+B8BCBYXplfFVacA9VF5Bd2NzUHYRCtibmolj52iSwOeWGdcmDhcJ0XMTwmRjISL46R00iqLA86ga3fDbRmw2AP849zZxuXRPu7Xg41Cpyn5Duc/A3RXFikp/F6BIGgG8/NRwWV4qYUiPAfdSRaHjVOHVmfe2oQ0B8+zuicyHapWA6wrs6W9dWqW/tZgrP5Y8YfDgNXhA8EssOdX9N5QpxMjwDGmA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=tszIbXkBraTqGp29c7/7twATeW0D90xuu5uPIEBuM9k=; b=UO4RQZBt7j2l7U8diWskVX2kNxk9RXQZuyxe4PffALjjkUY5G97FuvGan+LZ0/h9WvC6sKRHmHnvc0ARqh91gaxVc9M66qUlfPor4tUzrU85wFcysNUgeYRoH6kQFUSJSCzSlQp9pfbKGwlg/IaH6zwcWjiqVwjpozSdZyF0mNUuWG4ZHTADQKbITJIuAq76w0puFqU25rrw7bVxTIoFOnNmNvPZVVqOn5o8YggGQrH9ThVGsIr2S9LxvbXN+zgIiRl/DIIVa8LW836ulLNErpwULsT02Nd0eL39JPmL+U2fs7Jmm+cbMjxDa4KeSg3ScasHDa8y4Gome5hixnj1VA== Received: from CH3PR12MB8659.namprd12.prod.outlook.com (2603:10b6:610:17c::13) by PH7PR12MB7795.namprd12.prod.outlook.com (2603:10b6:510:278::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8048.25; Thu, 17 Oct 2024 16:47:15 +0000 Received: from CH3PR12MB8659.namprd12.prod.outlook.com ([fe80::6eb6:7d37:7b4b:1732]) by CH3PR12MB8659.namprd12.prod.outlook.com ([fe80::6eb6:7d37:7b4b:1732%4]) with mapi id 15.20.8069.016; Thu, 17 Oct 2024 16:47:14 +0000 Date: Thu, 17 Oct 2024 13:47:13 -0300 From: Jason Gunthorpe To: Peter Xu Cc: David Hildenbrand , Ackerley Tng , tabba@google.com, quic_eberman@quicinc.com, roypat@amazon.co.uk, rientjes@google.com, fvdl@google.com, jthoughton@google.com, seanjc@google.com, pbonzini@redhat.com, zhiquan1.li@intel.com, fan.du@intel.com, jun.miao@intel.com, isaku.yamahata@intel.com, muchun.song@linux.dev, erdemaktas@google.com, vannapurve@google.com, qperret@google.com, jhubbard@nvidia.com, willy@infradead.org, shuah@kernel.org, brauner@kernel.org, bfoster@redhat.com, kent.overstreet@linux.dev, pvorel@suse.cz, rppt@kernel.org, richard.weiyang@gmail.com, anup@brainfault.org, haibo1.xu@intel.com, ajones@ventanamicro.com, vkuznets@redhat.com, maciej.wieczor-retman@intel.com, pgonda@google.com, oliver.upton@linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [RFC PATCH 26/39] KVM: guest_memfd: Track faultability within a struct kvm_gmem_private Message-ID: <20241017164713.GF3559746@nvidia.com> References: <1d243dde-2ddf-4875-890d-e6bb47931e40@redhat.com> <20241016225157.GQ3559746@nvidia.com> <20241016235424.GU3559746@nvidia.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: BL0PR02CA0066.namprd02.prod.outlook.com (2603:10b6:207:3d::43) To CH3PR12MB8659.namprd12.prod.outlook.com (2603:10b6:610:17c::13) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR12MB8659:EE_|PH7PR12MB7795:EE_ X-MS-Office365-Filtering-Correlation-Id: c95c332b-48ad-4414-d860-08dceecb5a9f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|7416014|376014|366016; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?o90uudqH/3KsNmyRTgCtTzA3NXzLB3RRW3oCtHMF3zqXnD8tkH8/72IcgYNJ?= =?us-ascii?Q?sjuXCuggRMbv9T/P5WXxyrOg/5o3VKBl0s4q5RGeKoeyyqNbFZH78DKaRWrA?= =?us-ascii?Q?DSf1PiRJ693BrkSU+8rliLaMAoo/rR7th80zKjziwDZHnJaP5e7vuHKYhFVv?= =?us-ascii?Q?h/6jtwoza8ef7sdtTvk5Omp0j81fSInkUzsLPSfK6y8HIBXii2SZU2YnpThz?= =?us-ascii?Q?98mIDMjVnTSXah9fzmKfcMafHL/Fb436ka00A9gwlSJ9KFkMSHU9UydUIFw3?= =?us-ascii?Q?LxhU8fN/C3Bng+XdCmeg1pQMxBlb5xCwVhG6xgFcynL1ot34nnZYBJmoTqu6?= =?us-ascii?Q?v0CYM17rLFsrpkh891rKT+TxYQie3UXURbPMV3UugKyn0xnwRchdHyijbdbw?= =?us-ascii?Q?TFPzetu7i1tO861yGDS2WFBC5hFAIJGMzYKBlND1WV+NE5xV8wgpx3f2fAWp?= =?us-ascii?Q?FrI9NO5ikDz48ieMcODCe9iz60Sgkoq8jkGcrlK3V4kKlErvAJVuIoSi0iuY?= =?us-ascii?Q?uYHLUcp06qhBmsvO5kuFc/BYtrVGOaaitwd07Lzka5OBoVdrzcV1/D0wV0Cq?= =?us-ascii?Q?+ffzF0eTXG0lz25NjDS6JjfJ/8fUY2usbg7xT68reFtn156wVCmtB3cOiGPm?= =?us-ascii?Q?SepuK6ASjfMdERsRM/0bUAwd35xanBDhR9/FZPe0bvxpSR4c7l574Yx2OgCx?= =?us-ascii?Q?aXFZfT0OfaS3PZO9Zp1NRelepkR022+fqr2kvOFxF6mEEhD5c6ONxMVYFPru?= =?us-ascii?Q?OXkWo/NClT4DFNHdBw0Wr2dmYwVW3jSh4DMB5+ANZyyNv93NCWKuPeD66ieS?= =?us-ascii?Q?sgSg+NfUQn5D58HIbkdHORWaW1VBBi2p4+h03VLPC8Zsft0Zodn9Loh+6/qc?= =?us-ascii?Q?Zy132kshZnQLG9akfPsQ9/wqRiZYJufzRSM1AHWpUer0MZ1kEx1MP1860rjT?= =?us-ascii?Q?Ng0QiMKxt9XZ8La7oLSQ0/4Xs1I1G/mCyTA+cwBNWIKHVakEKCnrf5xiIdLi?= =?us-ascii?Q?KkD4kN2NqGcJyf4xfx8mKkIIi9sch0EXg26rIaF+rZ/B8C0aWgO9dwEkCOBu?= =?us-ascii?Q?Q+hR8V0grDcuCfKe3c8yX7pX6OYz8CMCrAyfguKUp5tfmOT5MvQ2zGlBYLfd?= =?us-ascii?Q?KO/aKEMzQBfO4UuJUNIScGKhK7XTKzQXcB2vZ5gnLt8r9f3aBKpH/6576jmK?= =?us-ascii?Q?lkMNNxACYs7qmACBJ5fhmH36tYuZhdjOLWLJcW4Diea/1qMCw2NkexglStge?= =?us-ascii?Q?tSgtA62zcxQ5DG5tFW4G7T0ZSHVB64GSngY6pv9C10NDN8V1uMkmo54JRuO6?= =?us-ascii?Q?fa77V/zjOHAuZ9SIil4Zd2yW?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH3PR12MB8659.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(7416014)(376014)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?CcE9pb4GNUKzyEcxareJMEHhTiWiViMT2FrGGjX4qIUyhh18UMBWR2z7WLpJ?= =?us-ascii?Q?Z6umDQ6oJ1KuJgsrdX0Tdh6I0NOuoaH7sHdPPnSKYIKfQ5RK7XX8wEDmr0QC?= =?us-ascii?Q?viQ8jeESBYKzTompV+Ly1KQnk2Grvfx4I0ZY5p8c9eP8pjkWxC/5idWxQO3b?= =?us-ascii?Q?wdhX+q3vRThlIIfdn/P8wt7TFImQlJnGOnCYC4RKcDcSihR65ohcyQOkM4uu?= =?us-ascii?Q?3um+/RxQxnPG2iOXZ6V3UCknrJOiylDHC65FC13IzrAolckYOBiI5Dx6EVsT?= =?us-ascii?Q?JmwYd2RDNyfB73wQdDkjlzgpLg7ymOH8z+LT+2466CjBoL8scZ5RYRg4RPI5?= =?us-ascii?Q?gO5QwHoN+JjPmFp53MeD5nSY2R+hFXPtVq2g0F30P9YuScHTB1BNJzaYPeYv?= =?us-ascii?Q?rkSN7Z3GADZjHhUZjNPZveOSv4VjT9u5B+5Ccot6TsaS4DKkUGPMvx363N3M?= =?us-ascii?Q?sJ3BpIxHanovG1pA2uPOZPCwIaD+SmfV7Z8Jol0EBg672RQjWBoc1aIzOZbq?= =?us-ascii?Q?bH0uFvcy9EZZYlXdfMuME0WPEXQAnUBhkKuGsVWrCN3tJOaZiUYa3u+fhyIm?= =?us-ascii?Q?oBL+Ki0rXj1vZfVRzFCsiKB01FSRcZ8K5nxHF/jvnUAhZum3/jtK/eOFMBrf?= =?us-ascii?Q?UF369SJCHyOH/pDhSjbP2Nn/3JpV8ql3NjH/PYkNecOc1N9EbiK7ZbcfMjDI?= =?us-ascii?Q?gGj/kyhR6XLpZU/VJKsVf+fvCUueaFtbVNYdNwdFtBQLR/TJpf3+senBHcNl?= =?us-ascii?Q?FmwiJKPdnSvhTmQDUiVyiyDL2P3kMxvX0OdNnvAver7xArL81nkliBwYxFf+?= =?us-ascii?Q?RLC+IwIKjNx29i2CZBikkk4PdlzmFpTeHSF5ieZ3ZehD8oRXH5UX7q4xRbyT?= =?us-ascii?Q?HJypMQF4DQ1OUinkFC5/T0Qygaa3IN1ZQ5XfzX5p3gcRtl7qdIcT7d2PKSY7?= =?us-ascii?Q?TXGEwMfLrvrVqD3nDhIBGy/RJivt19uWMWahUCDo/682SsOp5lm5oTnU4VoK?= =?us-ascii?Q?i4iSpTQJiCbBIHlcZvR33SEL/oiYa/2SsPBwqD+/HyKe4ga1Sqzgy6ztHXN3?= =?us-ascii?Q?uKKXYDxukSQCcPsqIPo2oazvcjKbYBUchjX1xjmMPS9of/xT5v0MbL+b1rrn?= =?us-ascii?Q?9cC50MmPxhAzvRhVbA7v9hYXazIxDe+odUR9MGp064MW9GC7QRvMVUtBKYo0?= =?us-ascii?Q?VcbG5BN7cnaigDXuFuQuuP0UPP5ClyTn4XhRRF199Lw5nI2XH/wyk4J88caG?= =?us-ascii?Q?51V7aUqx2aO16uOXehgGS+lT9M1CSQYrx2ba3xCLf9pUjQWiAEtyocG9ddwp?= =?us-ascii?Q?07jd7Or/mK9f/QitUglfFX8DbflOszgqtX6ZoolptuGZQGRV9FOQoGEY6Yhk?= =?us-ascii?Q?glo8slOsmik1HgdJx4/wIDoLLst15DRkuhsh+5IxNIMaCbds4JXIEpnabdz8?= =?us-ascii?Q?5z9QTR1YvaP32797QCKaAXTlRXJ+QJZWSrBR8TbukJ/nvSL76JNWq7su7u1M?= =?us-ascii?Q?gVeTPditKExo0pPKYfn85+T9Olstm6vvr0CIL5SYbRxNCs8fkrROXUd0/9We?= =?us-ascii?Q?Uh1hS+Q1HdYbBQmD7og=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c95c332b-48ad-4414-d860-08dceecb5a9f X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Oct 2024 16:47:14.8287 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: YUiKxHze+sFMpXfAWEDTo8/fwzM2Iqpb5k92fKoKCk5hUPJ6Pjcyl7IneTy22WaW X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7795 X-Rspam-User: X-Rspamd-Queue-Id: 90894160016 X-Rspamd-Server: rspam01 X-Stat-Signature: b7qpfyqaswuje8o1xeonz4jcb17zqmrg X-HE-Tag: 1729183633-85966 X-HE-Meta: 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 qhP4vRFq QAbD7b9X5bX1y/l0hAbwXkAbnvng8K8QP4P3lswtmi/rhP93H6x5KcTSTcjTi9gzSZwlDu+k3rV3bSqCz8UZMSQwMe4CwmOde8QfyU58wNtpLIixv78G5pe999YFO3Rj/StyG+uZzE9rKpnk/c8o6tiddS4ph18c6/kh6EUwLjaLzdgKq/St5DwBZdGT0GYGVoWwGl/57Sa9w9+jGvorzsUK1jLa/sRnoE+IwCacULTG0T0C+E780bKrZJbMtSE3xIsmI0Qk3GUJUuxQGOrOmkRs0erdD+axTLwj73xOYIzt9bW+WUDYNaBJFPFX5rvc9smxMPBY1wUofCHKKPmPcL3AxKUK9su7XYy5PYYJV0gkNCGzh6rFQZnq5Rk2YCMV5Se2hUrerVxotAK+qxauBcGsNA+Vlf3CSF9ExXDnYWZeLxIwsQdOZgI8q4A== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, 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 Thu, Oct 17, 2024 at 10:58:29AM -0400, Peter Xu wrote: > My question was more torwards whether gmemfd could still expose the > possibility to be used in VA forms to other modules that may not support > fd+offsets yet. I keep hearing they don't want to support page pinning on a guestmemfd mapping, so VA based paths could not work. > I think as long as we can provide gmemfd VMAs like what this series > provides, it sounds possible to reuse the old VA interfaces before the CoCo > interfaces are ready, so that people can already start leveraging gmemfd > backing pages. And you definitely can't get the private pages out of the VA interface because all the VMA PTEs of private pages are non-present by definition. Hence, you must use the FD for a lot of use cases here. Jason