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 C93F8EFD23E for ; Wed, 25 Feb 2026 10:15:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C07326B00B0; Wed, 25 Feb 2026 05:15:43 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BB49B6B00B1; Wed, 25 Feb 2026 05:15:43 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A61AD6B00B4; Wed, 25 Feb 2026 05:15:43 -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 903E66B00B0 for ; Wed, 25 Feb 2026 05:15:43 -0500 (EST) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 2AEFB8BF93 for ; Wed, 25 Feb 2026 10:15:43 +0000 (UTC) X-FDA: 84482572566.04.AA3F788 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf23.hostedemail.com (Postfix) with ESMTP id 9B4D4140005 for ; Wed, 25 Feb 2026 10:15:39 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=jPte+dRV; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=mqQ1iStj; spf=pass (imf23.hostedemail.com: domain of harry.yoo@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=harry.yoo@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=1772014539; a=rsa-sha256; cv=pass; b=0uBvdDWv2X4KY8qYuc5UwRevWnajxbPcaRa3HC41oWYcve0qt7XkByBZ1Rt52xscwjEUGn lkHgRH1Etfu6HUNH58MByqiXCMt49aT03wf0gnqN2/g2Lm26mAF9MTMcrWztaQfrJ8Gdf0 iZlIPpuh1Po/kexXQM19HQGhuvP8LIQ= ARC-Authentication-Results: i=2; imf23.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=jPte+dRV; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=mqQ1iStj; spf=pass (imf23.hostedemail.com: domain of harry.yoo@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=harry.yoo@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=1772014539; 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=JE2ZrMmFImNpu1AUa2FsMgZ2da5rAmxz2FWbcVlH0jY=; b=ZKuR45VNLyFUvY4hLVxMHx7KMwm4L09f1vrMRsqb3PirIpWc+oPjPCMcm6Y3mU7G62TZQa aXFnIvbklW8G8XKfST8WmJxE8xnrTXu8I86+TSpwS4WvbMVcHCkMAiLXpmDhoAk1n5mh0N 7l+dhBqfke4gqek7RqJTFQKyDeV+b7g= Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 61PA3jbG3928862; Wed, 25 Feb 2026 10:15:33 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=corp-2025-04-25; bh=JE2ZrMmFImNpu1AUa2 FsMgZ2da5rAmxz2FWbcVlH0jY=; b=jPte+dRVPEsaYvDe2YBWIrbLj8GQ5I7KjV rU6Kqz2YVKMjilPLNG+oNkGb73+JtBYu1aFSt0cKEu3xVgto6+njIDx6rNEiiONF uqAHogNxTfFTmXeDzgU8JNhrC1WfWzKfY86c3Y7tLkcHx6ivLY4leuLw4IQdV74T qrxJNWMPkcCnWEkhZuFZx7a8KQyeorZ4odfGY9APAAqk+nI3dLHSjt7lsoSuMGaY k9ZH6sv7uIEdBPZQ076PHOEo2UDygEm4kM4QnITpm4mQEUCAE9l/uvTdMdBoyYk6 Pb+xQLB65PnouHAFgiMCX43QV2Up7DUnVdFJiFEuLp1sAbnIAfvA== Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 4cf58qdtf7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 25 Feb 2026 10:15:32 +0000 (GMT) Received: from pps.filterd (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 61P9BP3C038677; Wed, 25 Feb 2026 10:15:31 GMT Received: from sn4pr0501cu005.outbound.protection.outlook.com (mail-southcentralusazon11011044.outbound.protection.outlook.com [40.93.194.44]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 4cf35n5hax-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 25 Feb 2026 10:15:31 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=WVLZG6ytN0bTSjrVkLl+WbwSB/klgL5/VMSvH7V7x4KtiTv8eOHkO9k7wd4rc2MHxikoS8/tn2Y5lzbVfyFpNtsoIlOswDiYo6yWwFaFaYTxA7GBxNFdaKTwek3nUDBLvRhXK0sngws234ldxzNGQl4npnV1n6f0pJEWWQEZt+Smf8WLOLghs4Mc4u1mmr0taOKQRAsgOq+25KyQsO9ZeMgsMtqbSaMRTiZokqHdILYfI+4+QnqD4irnjtqHxgI6cmDqBGpHWEd4bl2rJj4fg6r3dOBx8v0ioLK6z7WsywzVB825RNArhULFQenANmU3jut3N7JPoPpysrKmgjyd7A== 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=JE2ZrMmFImNpu1AUa2FsMgZ2da5rAmxz2FWbcVlH0jY=; b=ycWmRqjx0zwBzC5ffgUJiUwSnHNI0w7XCPdWCItuoUMUQv2QRFKIbmRwRMRnk8CSSQ91c/ehkk7altKs5wp75fVo7qlPLtGF6M8HSUMGOmjO9Aw9i0C/fJMpuWb20HlJNQdcZI9vHnbqPP8CJtUpI7z/ikfWWEwX08ytDsZ5LjQn9y1pkWDRnlRlhL0fDfbKvRGvd4FuaNjneYuZjti8rW6XxWeOZ1pEBdQUzrIY8cqgi0/2Bg9lxOxR1WkOaueUFdV5+ir5rEFX5jtFrtK5VeXdKofzMtmG+k8O2VDiW7o7+IKcytXCHRICxQiSrzUC2WMkgVf/MnAkRkjYU6Dh6Q== 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=JE2ZrMmFImNpu1AUa2FsMgZ2da5rAmxz2FWbcVlH0jY=; b=mqQ1iStjQUygN4FmRM0T9JHJsI6igWkwfbgEAL0DFBDxrTJ9Wl8a/qNiVYKC6WjYE8wueF3PlOuKvocMlzFbdLbj9pE31vCl9c6RQrjItM8U8DNmZu/HdbAjCXvwZcp+yKwPl9TD2kr6hMdP29dSjkr5N+Zq4YopY7gaAfaPlWA= Received: from CH3PR10MB7329.namprd10.prod.outlook.com (2603:10b6:610:12c::16) by MW6PR10MB7659.namprd10.prod.outlook.com (2603:10b6:303:246::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9632.22; Wed, 25 Feb 2026 10:15:28 +0000 Received: from CH3PR10MB7329.namprd10.prod.outlook.com ([fe80::c2a4:fdda:f0c2:6f71]) by CH3PR10MB7329.namprd10.prod.outlook.com ([fe80::c2a4:fdda:f0c2:6f71%7]) with mapi id 15.20.9632.017; Wed, 25 Feb 2026 10:15:28 +0000 Date: Wed, 25 Feb 2026 19:15:19 +0900 From: Harry Yoo To: Venkat Rao Bagalkote Cc: Vlastimil Babka , Andrew Morton , Christoph Lameter , David Rientjes , Roman Gushchin , Alexei Starovoitov , Hao Li , Suren Baghdasaryan , Shakeel Butt , Muchun Song , Johannes Weiner , Michal Hocko , cgroups@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] mm/slab: initialize slab->stride early to avoid memory ordering issues Message-ID: References: <20260223075809.19265-1-harry.yoo@oracle.com> <2d106583-4ec6-4da0-87ea-4ecad893b24f@linux.ibm.com> <84492f08-04c2-485c-9a18-cdafd5a9c3e5@linux.ibm.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <84492f08-04c2-485c-9a18-cdafd5a9c3e5@linux.ibm.com> X-ClientProxiedBy: SE2P216CA0023.KORP216.PROD.OUTLOOK.COM (2603:1096:101:114::12) To CH3PR10MB7329.namprd10.prod.outlook.com (2603:10b6:610:12c::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR10MB7329:EE_|MW6PR10MB7659:EE_ X-MS-Office365-Filtering-Correlation-Id: f00d9e33-6704-4e20-6f4f-08de7456cc8d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|366016|1800799024; X-Microsoft-Antispam-Message-Info: aLqzfhdIzNsKJTpyjd40uXVGCTQHTikLZsA9Ik+3wGxxip4m39jhxDb++bZGsH2KJS17k2DswN72ve5x5+a7ZBs9vN0cAgi/gQynO9+a1tNM+neEKA5Wcx6SvHGVQNMVqP8WzJvajYqWHybmg1LMnfPqaOPxS4Nsi0kMIEcAMbXFcoxSXysJgZypdVnpNGuF4HcO3kWx2yS68IAp64oYkyLYOvwifxvTxdQncctszjiVAvaqwpIzEmGe3x9KH2y6DsEE4uBrWKFYdjFN+wq7YyuUkBvO+MYNcSc1cMd+sVyO9g8naTDbhSZPLamPgmIlw99WiO7cCwb/s1gQQru2WKpFxs5VcNmxVyexCoIbDvcU2YgrZb1Jf7kh9g8hDaji4zqOgVa7wPxqcvycENt3y2j974/B77Ko6ZkPPQwFVoDnsrRsvxh4h2Fu3Q95msqgtQdhVTNI+Fi2pKiqU/zrkmWIw1e19U+tEXqeEcKnnU8QgjzufAyJZGLx9i6WZoVymn9/H9q+/vaSFSxPHyp+/1BOnfUBdKmEoxsnj1KMpXeX7YwZGGTJgS1sRvB4YdzI1yjq/J92vf6PIhtbuOb7lQoksXPyhY3RTNZuRcvPAImohob07yxdd0SkZTsyv9Yg4Wie82RhpzOOxuRTtv9X52h2zVvkVQBonDcKj8aoMjjAivFA6YKIbooYaK5twq8EMJp56ZJM96Bn7EVhkj4sPA0K7OYaJswqhTA0jd0eABM= 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)(376014)(7416014)(366016)(1800799024);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?7vWoqKSrNqWycaDBBq4xWaTVFkQkUwKJLQiRrnwt/wY9dGTuHvTmQtXfQQG8?= =?us-ascii?Q?TLNxfI9v7mQh2xDHqnZUcJsrwzSKzQhnX9kIwLIoqczpRsDiHzo8HuJY4P4E?= =?us-ascii?Q?3FyPFlbMTTjBXVMWFum4xjT58310tZpSR7+MXFWUJFayeicZWPIr0Qcdl+D9?= =?us-ascii?Q?xpgIkQtN+gyBLpZaot9jSxgSYIdzSrCDyQWu3RMtDyVO6wYAAoQIPiJ5LJXp?= =?us-ascii?Q?48etJOLajLnt9/6zaf8T/X1p4mZ5rf2PlXctEofNt1XAAExdJj98P7fLGVQV?= =?us-ascii?Q?PPv3cPmFv0GopCaIj157IYiUFN6F1Vl+1O2BbJafqcjmnfcbVh++Htf1j0Oo?= =?us-ascii?Q?xEJ0ebCS2tYJtFnupl1eIYYMPu6KZd0SkqWZ7hDIIC0qhnF4e0Y65Lpummid?= =?us-ascii?Q?tNOR8GvcVKGHSAZBHnaRWaWdRa3QxOJGq5gOCPNPMluaj1DKmYqnO2GbyMu0?= =?us-ascii?Q?z4BcKDLB+lPnJViKR1hVZ0EeTiwWUAnPB4OzpbNbl4tzmBfhH8yIrDO64X0E?= =?us-ascii?Q?mZCZTwtsJL/jMe20emF3RQNUJMuYflrVtGYArodvT9UIk32S3CepMJUO6zdH?= =?us-ascii?Q?EvJf1wXIrJIn9ASpqja62wiicZVxqFKB9415SXCrft2k/rduMJdKzP59oh9R?= =?us-ascii?Q?yzG3dloqwlSGONn7hOJgoRimlCxvJgWv3srldXOQ1e4xr+FJV6Ex4vc4eDS3?= =?us-ascii?Q?NRadUUsv6bK/Llvl7czCeJWJSGSqoMxv/mKly+z4wEZj+g5IxNfderfm2eNX?= =?us-ascii?Q?aJAmZUeG34L0vwkIrp4Mp3N+Jw8EVARj81HMCmN0u521th5rQCArk5skDn75?= =?us-ascii?Q?PwrK4eLRcyAQPE4AfUUmgcPI57iZSn1pEs7ueIJ/bnu3jbB4/Wnl9hgV5Qxq?= =?us-ascii?Q?q/tDpNfT4GCZsliddxZx6THUoWVmFmjeOHgu65G43liXuC2jkPBdXVmmIv5Y?= =?us-ascii?Q?Rq4HQ7qWbmtYieC4GQPFNfqHiposZ9wEPq9ABFw45iQGcvOy++g0MpotWliH?= =?us-ascii?Q?i5ZAV+YlRY1aMbNDiima7TA5+R77szkBkhz/4GOzHoFN9yio7ovTmYCXtRGT?= =?us-ascii?Q?oFE/+M1FudoRMGmheDvwMrIbf2U9JsrI17k3zuZ6ZViA/9V79KitsDtowCyc?= =?us-ascii?Q?z7JtPa7NEZPG3pof7rPteqQLPhX2AO088uOsQLZ+B2bGBAJeVMo1HKLS25X3?= =?us-ascii?Q?+7KlW2ztC+ubfqaya7xGXLB3r8r4tiIZEUgj1MKLy1O4hlB6qi8VBOy2p/xU?= =?us-ascii?Q?fEyluhHMZ89ul3lgXbKznkKgMxFEdcQ4eopkmLaJVvvjqm5I1zphrUsyiufv?= =?us-ascii?Q?oYEiaGjfmsoW/g5BISeLx7S7Gx5iFGPD4V2LJAENZh5knrjQzdY+kOQkoaOA?= =?us-ascii?Q?wYJRNi5x9QtJnbhCGNR5xzwfFooo7VZq+qNk5bgps2GmKFPYUMRi40jVVJ3v?= =?us-ascii?Q?Lcw0kU/cSWgwVR7l2h25BngcrzqrmXz2daQfWjFGxYXwLM8zliJDxISuZH0s?= =?us-ascii?Q?vPZRbBHn4+DhoSZga2Kys/r5GbJufYiqYjM7JUE+oEPSwkqaEN5TEP7CZmnB?= =?us-ascii?Q?fBwzVI5ZobhjfeNq8T9ctWVPg+p9buCD3humZwYxEZA4ZTxYxK5C5jqBSj5q?= =?us-ascii?Q?9L/PgQg3ztB21R0gl9aRg+eR+vJyU/oDZ/HD5u747OtdcEWNpNE9VOPTcvy5?= =?us-ascii?Q?SI8spFFWEQBb5XU2G7+nF9XHkYdkrC930VtsokNuNmt3KVE/YbdP7tikwxd/?= =?us-ascii?Q?XDZb+lO65w=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: f00d9e33-6704-4e20-6f4f-08de7456cc8d X-MS-Exchange-CrossTenant-AuthSource: CH3PR10MB7329.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Feb 2026 10:15:28.4096 (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: AVcWwYPqOFWXx8V61SuusSopAGbl5lgABKBK7N/Y/STIxkM1KuD3te5TTKJXqyWwPVr+hqcQut0u6XmTLhtqCw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW6PR10MB7659 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-02-24_03,2026-02-23_03,2025-10-01_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 mlxscore=0 suspectscore=0 spamscore=0 bulkscore=0 adultscore=0 malwarescore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2602130000 definitions=main-2602250100 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMjI1MDEwMCBTYWx0ZWRfX6z4FVa4VxmJx mf/lsA+++ItvroBo4uMsvzu+AJXwDAHLe77UXnOQnLt4XYL4NxOXxieaoU8ty8rxe9/MYJNqvnj FFptJaxQfB8X4VfaUMXMGfFQKu95DLaAfq/G+hb2XgzAxVA5jJOmDcSNQEqyM2Q4pyFmFCepJYO qeB9B1IZhkUAMGGIc9MTdyVpTyk8cyznjWNG5uY5iG8VEHBB1ZQ++cm2rQi/EXMaS8pbNgeh9G2 BQYgJNuxL5kEJs4r2MNE4+jq/zW81lh+4aXhhtAEPa/DjCtKbUEoX3jA3dOVIBwrn9ky5v5eIAH Y32Dw/kgn6ZRpJxDMHz/tfFD8y8ME/fCQIaNMtPmNwqJ9DFqFFGUFaR3VVPCnrFmzBIVEwEcqQT skoVcqahDNiD32PzdBmxLvNs0Uc3fwwMy5+Z9h9r9GAAbHtUpKwilJPQ9B1mamKwVLMZ6YqTn08 Ak2urj5ZkWMEAj7ZELI0NN4jzOftD6tuTSl1Y/Kg= X-Authority-Analysis: v=2.4 cv=XNc9iAhE c=1 sm=1 tr=0 ts=699ecbc4 b=1 cx=c_pps a=zPCbziy225d3KhSqZt3L1A==:117 a=zPCbziy225d3KhSqZt3L1A==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=xqWC_Br6kY4A:10 a=kj9zAlcOel0A:10 a=HzLeVaNsDn8A:10 a=GoEa3M9JfhUA:10 a=VkNPw1HP01LnGYTKEx00:22 a=Mpw57Om8IfrbqaoTuvik:22 a=GgsMoib0sEa3-_RKJdDe:22 a=yPCof4ZbAAAA:8 a=wNQek9p9X8fHaaAc_nAA:9 a=CjuIK1q_8ugA:10 cc=ntf awl=host:12261 X-Proofpoint-ORIG-GUID: Nnw3X8xHz4ICKnfgTFJIWqFFXZ9NrH05 X-Proofpoint-GUID: Nnw3X8xHz4ICKnfgTFJIWqFFXZ9NrH05 X-Rspamd-Queue-Id: 9B4D4140005 X-Stat-Signature: egfi4f44xmmnsgw6zx7hijiprqqg8i6x X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1772014539-838753 X-HE-Meta: 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 fLwwiqQG 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Feb 25, 2026 at 02:44:24PM +0530, Venkat Rao Bagalkote wrote: > > > Thanks for the patch. I did ran the complete test suite, and unfortunately > > > issue is reproducing. > > > Oops, thanks for confirming that it's still reproduced! > > That's really helpful. > > > > Perhaps I should start considering cases where it's not a memory > > ordering issue, but let's check one more thing before moving on. > > could you please test if it still reproduces with the following patch? > > > > If it's still reproducible, it should not be due to the memory ordering > > issue between obj_exts and stride. > > > > ---8<--- > > From: Harry Yoo > > Date: Mon, 23 Feb 2026 16:58:09 +0900 > > Subject: mm/slab: enforce slab->stride -> slab->obj_exts ordering > > > > I tried to avoid unnecessary memory barriers for efficiency, > > but the original bug is still reproducible. > > > > Probably I missed a case where an object is allocated on a CPU > > and then freed on a different CPU without involving spinlock. > > > > I'm not sure if I did not cover edge cases or if it's caused by > > something other than memory ordering issue. > > > > Anyway, let's find out by introducing heavy memory barriers! > > > > Always ensure that updates to stride is visible before obj_exts. > > > > --- [...] > With this patch, issue is not reproduced. So looks good. Thanks a lot, Venkat! That's really helpful. I think that's enough signal to assume that memory ordering is playing a role here, unless it happens to be masking another issue. Even so, it's important to enforce the ordering anyway. But having smp_load_acquire() on every alloc/free fastpath doesn't sound great to me. Let me think a bit about it and come up with a reasonable solution (this time, hopefully no hole in the ordering). Since it's a bug I'm working on it with high priority. Again, thanks a lot for testing! -- Cheers, Harry / Hyeonggon