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 4F039D5B144 for ; Mon, 28 Oct 2024 20:18:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BEDD36B00A2; Mon, 28 Oct 2024 16:18:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B9D106B00A3; Mon, 28 Oct 2024 16:18:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A17476B00A4; Mon, 28 Oct 2024 16:18:06 -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 7AAC16B00A2 for ; Mon, 28 Oct 2024 16:18:06 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id E74CF14077C for ; Mon, 28 Oct 2024 20:18:05 +0000 (UTC) X-FDA: 82724121858.24.F9E8594 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf13.hostedemail.com (Postfix) with ESMTP id 22BF02001C for ; Mon, 28 Oct 2024 20:17:37 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2023-11-20 header.b="Ile/H5R9"; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=t0fZGjfs; spf=pass (imf13.hostedemail.com: domain of lorenzo.stoakes@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=lorenzo.stoakes@oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1"); 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=1730146628; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=yoUm8YtmZTzUNEIgdimZFa5LFGCg32E/BfAQHFdS3mA=; b=YsjEUrItIaR8C6KWCmFWjPQOZ4Po8MwIOdnc/zVYHjNOVeOvofjYRgSs5M9xCq8N6X9OfL XmwfACS6AyM35CMtonfG/wAmL+MrfBm7vNz8vDR1kpkn3MVZBaG4FTx+j5FSVk2RyoH2f9 EvklTQrxVVFZVZ04FIjQfrf1WUnjg5w= ARC-Authentication-Results: i=2; imf13.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2023-11-20 header.b="Ile/H5R9"; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=t0fZGjfs; spf=pass (imf13.hostedemail.com: domain of lorenzo.stoakes@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=lorenzo.stoakes@oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1"); dmarc=pass (policy=reject) header.from=oracle.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1730146628; a=rsa-sha256; cv=pass; b=gSBw78NXhZSgUuwrBSKl22Un9LQSVoSAOk1Jrho4YcH4rABr7Q94G3lgaM0QdvsAfZbWgB x6tZNSFbYiDcIhlDewAL7ynTNCF9sVGIi4rrHAGLDAzUyDusc9GQ/6EM964mrFjg5RbzsM wkBPJMZCzrGcuVGIuecnvEaaEjyNP9A= Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49SEtdrS020885; Mon, 28 Oct 2024 20:17:52 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h= content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=corp-2023-11-20; bh=yoUm8YtmZTzUNEIgdi mZFa5LFGCg32E/BfAQHFdS3mA=; b=Ile/H5R903z1ej8Jq/NvEONXsE63YBodY7 mYVWhLasqrQvjaKCa3H5Rb1jtc6Od9DCKwSwxsJsF0ylHTJl1rn/wwB5tvDeRalU mO8I7XCsZ6cQllTcSbD+/Wim4ppzt7ZYLm5uzcyueBy/V4zxewV2qeRRObUMgpUZ 9fbtD/DxkhF0S3VlRnm1lAoQj4U/Sbl9Ibo3GY/AJu5dj+ErMCk/VqF0VGHZn24o oisvw2/gILy+vNOILhodQzB9ZM/TBVf4L1zFDcblk2YcnmW4EfYX11O3VpZJGbMo q3lN8cwGD0FKcIM9nmtryDAySmPYf+ZPX6OAYCA79/c1AJKiwBBw== Received: from phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta02.appoci.oracle.com [147.154.114.232]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 42grys3vw8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 28 Oct 2024 20:17:52 +0000 (GMT) Received: from pps.filterd (phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 49SKCiBR040035; Mon, 28 Oct 2024 20:17:51 GMT Received: from nam12-mw2-obe.outbound.protection.outlook.com (mail-mw2nam12lp2044.outbound.protection.outlook.com [104.47.66.44]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 42hnan0ghw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 28 Oct 2024 20:17:51 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=wRl437mtZT1pi+L8tbzMTWrbLXL5QpyKYRV6MPaAV1XIMtiZ1jilHC0zKdHNRtgywuIpeAbhw/63UNXBbKy4TmBrFaAWAb+Arya1GcU/GtDwgfn23911uxHyz3qC6h5/sDRWJ+nxorCG0h+VawDS+ofKh0ca+eeRdZ1Fa3ChQ87TbgVfG/6zPCLaxW/uq5xZAoSStYqUAWNbk3bXALV/aARYdxYkJjmzaN0kf2i0i9f3Ir2aw3kymgPuq99TqimMdM/954cfT55pgohHmx0oz5Dlbq1G7jgC918KQx7KSPXP7FQ16YRZQ5dLBy8HsdqCk5iUocdX2WWZCOfet10AfA== 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=yoUm8YtmZTzUNEIgdimZFa5LFGCg32E/BfAQHFdS3mA=; b=qTT2PZop1Xpr3zscFK4FrcdVGduXqZBCNb88Fq+Uc8Wpp11OY6g73tHbfySm6JLf7uvZUeHwjprii206bb9NFN1TefCo4B/5u+l7RskawuWyFE7IllcOardB/63iFfAH1qqoSqDzJq509a/5MMCOw72H00/pZEhEC+dGUsSaohdsybK83XoGYlKP9Y6Ihu8ytX67wsrxcmdjD/CkhJOLmI9S20yG8MGWJAjmmu7+IAcXTN0if1HC3A21aX5fLP9OhgcPnl+CESi73j8eYVxOqUhTUybsffAt0+S4wc+3+j54UTG4zZI72YM4QGWnJvLP5krJI3rNIKp9L0Le82p4Pw== 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=yoUm8YtmZTzUNEIgdimZFa5LFGCg32E/BfAQHFdS3mA=; b=t0fZGjfsR6UDpoS5SDccG38Pr9m/wdqnj9SWQb7qIa+XaXVCaXjZcREQnYoBUYcYMirDQU7wrofUKgvtwn+ayDBvs+Ld8k9VX71/tzNme4cG1w3hWzOiO1nJCCbC1yx4M3gfLa4WOoTsiQK1bn1qtZbYvkVvZrH5V8FavTqP+2I= Received: from BYAPR10MB3366.namprd10.prod.outlook.com (2603:10b6:a03:14f::25) by CH3PR10MB7164.namprd10.prod.outlook.com (2603:10b6:610:123::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8093.24; Mon, 28 Oct 2024 20:17:48 +0000 Received: from BYAPR10MB3366.namprd10.prod.outlook.com ([fe80::baf2:dff1:d471:1c9]) by BYAPR10MB3366.namprd10.prod.outlook.com ([fe80::baf2:dff1:d471:1c9%6]) with mapi id 15.20.8093.024; Mon, 28 Oct 2024 20:17:44 +0000 Date: Mon, 28 Oct 2024 20:17:39 +0000 From: Lorenzo Stoakes To: "Liam R. Howlett" , Linus Torvalds , Mark Brown , Andrew Morton , Vlastimil Babka , Jann Horn , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Peter Xu , linux-arm-kernel@lists.infradead.org, Catalin Marinas , Will Deacon , Aishwarya TCV Subject: Re: [PATCH hotfix 6.12 v2 4/8] mm: resolve faulty mmap_region() error path behaviour Message-ID: References: <6e8deda970b982e1e8ffd876e3cef342c292fbb5.1729715266.git.lorenzo.stoakes@oracle.com> <61461dcc-e455-450d-9c01-5465003fc31c@sirena.org.uk> <438f50c5-8b8c-444f-ae85-10e5151f3f24@lucifer.local> <57mgmdx7wgfwci3yo3ggkmcnm3ujamgkwcccm77ypvmer5tegn@opiq3ceh2uvy> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: LO4P123CA0213.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:1a5::20) To BYAPR10MB3366.namprd10.prod.outlook.com (2603:10b6:a03:14f::25) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BYAPR10MB3366:EE_|CH3PR10MB7164:EE_ X-MS-Office365-Filtering-Correlation-Id: 99cbed74-7556-4feb-56c6-08dcf78d950f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|376014|1800799024|921020; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?qsCJqJGDSiMrQCp99FWHocAvY7akDjciv2A7HxqR2eesO+myGS/fhVKJRHdW?= =?us-ascii?Q?ruJzNgXomXKnKjS+HBMgfnM7rw1IcIcANfArvbghAhMDm78pVtB8BKhAplRw?= =?us-ascii?Q?DEPh2oIAhyrWcRJMir1UnGXT6+X1cZpZcrUJG3uNxz6+NOsd1aGAZmLXYbfJ?= =?us-ascii?Q?gMvR0OCDcsQgD6jYaWE9dWwmWQqSNhRvcK32ya4v/t0b62GCHZt3DERQIswv?= =?us-ascii?Q?3AIDcNpmGjL1KwAQwGDTMTp+2XjxBrVXkAYT20STJrZe9A314HKsbK6P5ala?= =?us-ascii?Q?hXybhMXzVsQ/aBdO+4xYzlX016XtPE3r6l0xnbkeVSY1LlOCOVg35qnyDfCE?= =?us-ascii?Q?vpedom+rBlyeF1Bnjq8C7gqzrq5WbIhKJhA5wby6avdccvu/hHWyVhzh/AJf?= =?us-ascii?Q?c/8df59huxZhDpiaBCIyNR60KK8kAvbP9m9ZihUa0tkprZLk98Os61VMIJ2U?= =?us-ascii?Q?SY/aHJjPomLMSh0mY7GNQkhkeB1CnA4LRaZO5q14NMS1ESoeCbhTh0DKcggn?= =?us-ascii?Q?MkHaAwNOBNWZRlHooYH4JnXxkaWHJk5e688Ll7xINCnVYAxkEbYul+QGKhVQ?= =?us-ascii?Q?OMvQPgpcx1lH7MMwgcK7YOnU76eQMYpg0XEk+qOk2YN10wfiRGiU6EQ5oksn?= =?us-ascii?Q?KJ6I7RfcbP4WbVi8G5wDM6ldsbemPpd0MdNEcKpyMOOe1zG1rlET2e15f3cF?= =?us-ascii?Q?k3+Vhsku1n3P4Nn1LQGWb6E41wgDcbQCGXQAHsdbP9J8FMVU458B71DICN8W?= =?us-ascii?Q?U0aoJi8yw7lauC+3trESJR0Zz8zz7vZ+9jwbcJIKRk3XSAFXrJvuUtcrjrGA?= =?us-ascii?Q?j2li6ippprlj0QxEweVFVGEbY66v/PWnmpuDo+JhYdBT1RhgQsibcpZTjHND?= =?us-ascii?Q?EZ1abQIZKq0iiN/lcGGnomvqExMbG+NnFjSCU759sYXHdoeLnJdsoCb8PR6Y?= =?us-ascii?Q?kE9W4aetqxZoxCiay8L2yMyJslAfr13aKp7L4oQovX56aR0M5yDbspp5NJU3?= =?us-ascii?Q?Xm5doZq9laDOCsKsZzdDvUtBgj2M3LPHxtw4AK3YwBP7IobF8gLqxFAHwqCt?= =?us-ascii?Q?58xQx3p57geXXNZdgm42inSsWogtDbR2ZD9Gn2SGMBJ3mpBFcukfog8zRyeY?= =?us-ascii?Q?BLYD19VYAvaapseY3XdAl84FbCoo/jaen2O1oxw/DDWc3HOD/65S67q796MV?= =?us-ascii?Q?jX4Yo3ofpYRlvT2cSgmiajqn/6/0GRQ072xqwTKUGymzdKRuu546fc3tsfq3?= =?us-ascii?Q?mk6PiFCT6kEeAPWDUQG1QGM8FZesgoxGDsYkT99tsaP3QvDbr2AhRGXoW2vH?= =?us-ascii?Q?3MIDyhhMteooN1xKZhyF4W4UVtVTyCSvLr3UOdGT4u/30cdDbD3CNIVFcxQA?= =?us-ascii?Q?Ay7BmME=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR10MB3366.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(7416014)(376014)(1800799024)(921020);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ZZJ3mzgnvzC3m9bg2C4+xyaEyJHz95XEiP3rKH5UdD/jwN8Ix9oeES358Ewe?= =?us-ascii?Q?h367msndReqiRZLOo21ztLv0mpjq1/iAI4CaTpxI/yihpksjEyCqZvxu5B4G?= =?us-ascii?Q?Hicj+QFp6hWogMyLAPqtk2aoPAzxkJlJmQFPiUjmbj87bMWqVlyi8QY2iHiR?= =?us-ascii?Q?AnAJXmB/2xWeDZyIp93sSaXK4kjlKoYPCOr91qFYajtCeXTW25PhShJbMb7i?= =?us-ascii?Q?PC60WyMBrgAV2s/uYHM8lKYXW9qglO3gWzbhZOsjqDUkYw4YnllVKaa32MVc?= =?us-ascii?Q?dMgRCNZszxnRVaEHD7upyzmdMsuq0YG47Kqf8VEao0vmD1g/sJpxiWK/dQ3h?= =?us-ascii?Q?jrDPvUT1TvvibcR0v/lYBHh7ZS+6IRMoKoso6UooJE2rvP/KQKPV43y69W3E?= =?us-ascii?Q?0pEaD+INvxIH1Dyvl//DlHaox9bPLAHm/0ARWD0FdkwriaVrQRGk4lrUaSt8?= =?us-ascii?Q?POBJnlfqBZo8kXnB0CwalmaypAt89fquJ47EaQ8nO43MY8CWnV++jC3ZHy08?= =?us-ascii?Q?KOdzqpEDtvyypMsxpBywPFeLB9f68E8Ce/3mrhMw35+MNVBnCydZnz513skw?= =?us-ascii?Q?eui533PeyEDgp/PzHbJz50nsB82MvQAUmHISrg+TIwjuyBwznJKRNEm/Ogfi?= =?us-ascii?Q?p766IjsJGYlAlgzZocWYyLPiXs1UOPqQgZRDwiIqeKK0oQ2lqVkfp9cEma6w?= =?us-ascii?Q?pYXOtWapxwL5+c6V7PmQ06sm4I/2E4IZoi7ZXeSsLsHXhfDN8Bi7237RAYHv?= =?us-ascii?Q?pIMcmSthA0YF/SVdt9WBwjGBMamZ8xbGLpxqHWpZszJB2Ev/kCzZnMCMk/yf?= =?us-ascii?Q?6IZms5uCktOj8bsHInDEh4M2C2zVGgwHiuVARWRDi7f5hSrdMmiMyip0v5pJ?= =?us-ascii?Q?G3hBOcHK6oNavawkLdB1j+ZrhnCoOxUF8sslCAIs1t5RczrOlQAzK/uKgsnv?= =?us-ascii?Q?ED7u70qPZ/xsa9ZeCUzR5MjuzrJDELcpubZFoH94SBKEBWVAMVdmxBunjiE4?= =?us-ascii?Q?vqvtPuWs7GVz29XGM/FbEt5/r29rnPPvTgsj0OSwpc5gAIYi3n2y6DrfGYrh?= =?us-ascii?Q?dG00UQntTEmBsSaSxhc5GeZd6vEJVsxzRrMbTVJFSWbUNyFKoWPorJBYlsaQ?= =?us-ascii?Q?oEQUQDTv4UjwXJSFztS9uBXyMP9FYYpbHTcMM4XzaIIGt3pNWe9lGv42ZR0J?= =?us-ascii?Q?tLOahjrHonNv6BWEeElDQFP3+1opCL1S/Rn71c8WtSU4O9XFk4Dw3oe4iNz7?= =?us-ascii?Q?kOfJMAYHdvP0xk+rOlQApM1lP0rVMUa4ckeSWSl6j/j673FlXSuV2ltA/VUG?= =?us-ascii?Q?z8DGKojIV41arb8rdAvS03ipcm4Bp2msYnyFRddENwfgMEbrERVrx6Jx3cd9?= =?us-ascii?Q?i6v6MZiI61tSahjZ3bgOIl0wusP38B9GZ73VpUtEW7w4h/7GgnemQL+0jZFn?= =?us-ascii?Q?YAU/XpFIg/uG1APh+fvpwjbmFjUy5B5OVicwaLEV6Py/NEVtRza7ZRpmFZe8?= =?us-ascii?Q?u8wKBQvLIB6wsivF91HUtNbrD8ct33oIv/Fzl2EA5PqAfWfgDeWUbOnG8SWB?= =?us-ascii?Q?lGhREUJuTV/zwNhCrm0FKV6BWoB/ptAkmCx5Tt22zDn7Na0IBR5yb2otaAwu?= =?us-ascii?Q?ag=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: 99cbed74-7556-4feb-56c6-08dcf78d950f X-MS-Exchange-CrossTenant-AuthSource: BYAPR10MB3366.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Oct 2024 20:17:44.5562 (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: MVuOdKYqz0hiHQ1mGYmF21M6uJ9d8z45kYXS5Rh7wxG+ls3FgxZ+w37cJnpC7arBZ1z76duylve0La3iLTiTnfA9RQz3slbzfF2+9oNI3qg= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR10MB7164 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-28_09,2024-10-28_02,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 mlxscore=0 adultscore=0 mlxlogscore=999 phishscore=0 bulkscore=0 malwarescore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2409260000 definitions=main-2410280157 X-Proofpoint-ORIG-GUID: ZEVfy20TIX5XOapIl_xkn9l266RCDxXP X-Proofpoint-GUID: ZEVfy20TIX5XOapIl_xkn9l266RCDxXP X-Rspam-User: X-Stat-Signature: o3f1aeg54y5ox653mg4raefp4hegi6s1 X-Rspamd-Queue-Id: 22BF02001C X-Rspamd-Server: rspam11 X-HE-Tag: 1730146657-591560 X-HE-Meta: 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 adhPS75z 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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 Mon, Oct 28, 2024 at 04:00:29PM -0400, Liam R. Howlett wrote: > * Liam R. Howlett [241028 15:50]: > > * Lorenzo Stoakes [241028 15:14]: > > > On Mon, Oct 28, 2024 at 09:05:44AM -1000, Linus Torvalds wrote: > > > > On Mon, 28 Oct 2024 at 08:57, Lorenzo Stoakes > > > > wrote: > > > > > > > > > > So likely hook on your mapping changes flags to set VM_MTE | VM_MTE_ALLOWED and > > > > > expects this to be checked after (ugh). > > > > > > > > Gaah. Yes. mm/shmem.c: shmem_mmap() does > > > > > > > > /* arm64 - allow memory tagging on RAM-based files */ > > > > vm_flags_set(vma, VM_MTE_ALLOWED); > > > > > > > > and while I found the equivalent hack for the VM_SPARC_ADI case, I > > > > hadn't noticed that MTE thing. > > > > > > > > How very annoying. > > > > > > > > So the arch_validate_flags() case does need to be done after the ->mmap() call. > > > > > > > > How about just finalizing everything, and then doing a regular > > > > munmap() afterwards and returning an error (all still holding the mmap > > > > semaphore, of course). > > > > > > > > That still avoids the whole "partially completed mmap" case. > > > > > > > > Linus > > > > > > Yeah I was thinking the same... just bite the bullet, go through the whole damn > > > process and revert if arch_validate_flags() chokes. It also removes the ugly > > > #ifdef CONFIG_SPARC64 hack... > > > > > > This will litearlly only be applicable for these two cases and (hopefully) most > > > of the time you'd not fail it. > > > > > > I mean by then it'll be added into the rmap and such but nothing will be > > > populated yet and we shouldn't be able to fault as vma_start_write() should have > > > incremented the vma lock seqnum. > > > > > > Any issues from the RCU visibility stuff Liam? > > > > It is probably fine? We would see a mapping appear then disappear. > > We'd have a (benign) race with rmap for truncating the PTEs (but it's > > safe). Page faults would be stopped though. > > > > Unfortunately, we'd have to write to the vma tree so that we could... > > write to the vma tree. We'd have to somehow ensure munmap() is done > > with a gfp flag to ensure no failures as well... > > > > Maybe we should just call close on the vma again (and do whatever > > call_mmap() needs to undo)? > > I take it back, that won't work. > > > > > > > > > Any security problems Jann...? > > > > > > It'd suck to have to bring back a partial complete case. Though I do note we > > > handle errors from mmap_file() ok so we could still potentially handle that > > > there, but would sort of semi-undo some of the point of the series. I'm genuinely not opposed to a horrible, awful: #ifdef CONFIG_ARM64 if (file && file->f_ops == shmem_file_operations) vm_flags |= VM_MTE_ALLOWED; #endif Early in the operation prior to the arch_validate_flags() check. Just to get this over the finish line (original idea credit to Vlastimil, insane ugliness credit to me). Could be in a __arch_workarounds() type function heavily commented... I mean this is pretty gross but...