From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from CH5PR02CU005.outbound.protection.outlook.com (mail-northcentralusazon11012022.outbound.protection.outlook.com [40.107.200.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 77CBE3BC69C for ; Tue, 7 Jul 2026 20:34:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.200.22 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783456471; cv=fail; b=RWEl+5JrQiH3j4dJxH/bCckc6M5YJmyTKAHFpPi/WZzZer71fkvW6umDE0dYX4bnmJgGAxNzVROXqS9FgdTQcCXOYPoVvofvPtHrSqFMaZcCneuxvpSASAIgbxHjUFKu5og8WscACnvdAcfdSKhT7qXl/NN0sJ9RxBcAWUBw4II= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783456471; c=relaxed/simple; bh=RZhLOdaLrn+HXEGCbUEGh1FNls5apEv9+8XdMs8LxmA=; h=Content-Type:Date:Message-Id:Subject:Cc:To:From:References: In-Reply-To:MIME-Version; b=CGmRKMI8qDO4akFGvJpt8ZOdE/JflReIlArc7l896YpQu2KTFLaUTf7CRjNwQNBmx6e+fYWv+1sN0nn6/lGHkg9U/yHivgDxoHB/ZPTO5JX6kMdrVC7T9wY7Gzoel61rmGWUmlrVXYXYwugpPxNvjz2yu8dwd4anCj4Rf1x/PIc= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=qPWpNWw+; arc=fail smtp.client-ip=40.107.200.22 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="qPWpNWw+" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=XT1/cHrlebifSDanWOwP8j+aAbpA/IE4BFgbMGm98fxU569FC2UcNfUJae9UsIPq7gICPT7ohzhXcemOeByRRaCfXyii4r5tDvbsdtzmF6EZ6GovzYKTELa6VDcb+p2wWRIxzyV0ML3I6CNzhsQPMH0cQAGd1oPRq9prafypdhuSVzbAVSaudKzSoTjpipjA33b7PnZb4PbYnR0kbXmSCyluIjCAl13Wf0BJ9k0RRNkFpVmGgBOitkguBKFy4IaZwrtF6l0hfK0EtFml21VFqj1PLxS5GHpFNqktfYgMUBtLqvy6L18SDuyni7hQQVL6yYLVBtJIU85y8fZtt9wf3Q== 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=ScIr/j8NgES8SjgpxPAR20wLo04xff55JTRN/Mt42+U=; b=IrwkBGT/o6Il9+jKEy55Lz5buUT+4QuggdGslPqOkvW22GEKxG8bE/cG8Ayc6rRMHIjAehDQwx57GPlK/8ms41QoZlwZebtS04WwdAqHGNxWobPTUBMM2Hx2+Z0BU6xgTMqeE7F2b8P/Vle9UWuwvVMnNJSDLetRqIDA2NxETj8CLNP2VZd2mxFfnlwnhlaQi/N0HVjh+dEfDV1qjGqoqF0/y2pOmWndvo/jNPowTp5+hvJ2fDSY+HQZ/fjCMTN7vs77v6hzwWreNeUnwZiGYPM/8RKI1iwZmATe/JDH4H5ZrCchnSU6zBZ04J0fgFXL+5+Qsb6rUOy698x6XNhaFA== 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=ScIr/j8NgES8SjgpxPAR20wLo04xff55JTRN/Mt42+U=; b=qPWpNWw+OUMmIAChPmkP3Eymw4EKzBdrob6d5rDuFjjZx40keS06wmIl+FmNcr3c7Oc4QEKTOmjYZmsaxJgo+5qMgeKuFAuOk3hiCEn9vsLgyXfkSCnmKNHI5O8FhtM5nYU6sPh4sBcS3WbCcxk/xrrfSJzTIO2yV+g7lOkjUtcI+otTPmF1IecEpegE11iNHk+wHR1QMna6cG/nVkDfImiE/S2yWkXyYHQBdUnpr9U1zh5AojbZosKJBeKSQv4r1h4pKmSDUzOVFFsH6wb3s3+Ono5iLVc4mj47BR+tSAnhe+//QfaEZEEYKXhgp7Z5dbIUlDozgYvjjraBN8UQFw== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) by MN6PR12MB8591.namprd12.prod.outlook.com (2603:10b6:208:471::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.181.8; Tue, 7 Jul 2026 20:34:21 +0000 Received: from IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16]) by IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16%5]) with mapi id 15.21.0181.009; Tue, 7 Jul 2026 20:34:21 +0000 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Tue, 07 Jul 2026 16:33:42 -0400 Message-Id: Subject: Re: [PATCH 1/3] mm/mempolicy: skip device-private PMDs when queueing folios Cc: "sashiko-bot" To: "Usama Arif" , "Andrew Morton" , , , , , , , , , , , , , , , , , , , , , , From: "Zi Yan" X-Mailer: aerc 0.21.0 References: <20260707135255.292870-1-usama.arif@linux.dev> <20260707135255.292870-2-usama.arif@linux.dev> In-Reply-To: <20260707135255.292870-2-usama.arif@linux.dev> X-ClientProxiedBy: CH0PR03CA0045.namprd03.prod.outlook.com (2603:10b6:610:b3::20) To IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA0PR12MB8374:EE_|MN6PR12MB8591:EE_ X-MS-Office365-Filtering-Correlation-Id: b2fcf86a-b14a-4a53-11e7-08dedc67202c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|376014|366016|7416014|1800799024|22082099003|18002099003|6133799003|11063799006|56012099006|4143699003|921020; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:IA0PR12MB8374.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(23010399003)(376014)(366016)(7416014)(1800799024)(22082099003)(18002099003)(6133799003)(11063799006)(56012099006)(4143699003)(921020);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?MjE2dDBQcGZaVFJ5UjYwVlF5VCtESkFsV3ovc2phVjFRSVRpQ3NkTFdwMXM4?= =?utf-8?B?M1dZa1Exekc3ZHd5WUNiNFkwRVZWaWc2akJuUmNxa1FnQ1JuNHQ0RGRYMVNk?= =?utf-8?B?NlNtL3hEMlRYQkxYTjJyK1ZNUVdFbUIxMWo2cVpvWkx0a01TWkkreEtEZTBG?= =?utf-8?B?MklUdm1nUTdEUklaU1J3eVhLVXp0cUJmNXREZUZCTlAya0FTek5UT2o3elpv?= =?utf-8?B?c3FPbUVHRXJrYm5RMHhDRW9laE9pdVRGL05Nam5tRFIvaW42cm5wcm1BVlFW?= =?utf-8?B?L3dRVG9lT2FzSHNmbUZWWlhENDY2eXJMTEc3cWZQbEpNSm9oNlFKQXJRci9W?= =?utf-8?B?clZsYmZuSFFPQnZxNEtmU3p5aEl6TGlJdWdBNUM0WlE0WlJ4SmZFS1FndlVh?= =?utf-8?B?N2hCVUtDWlV4aGZ4aFArc3NIVDZzRGs1ODNQbFh5ZHlvdEFFWjJ0WmZPV05x?= =?utf-8?B?Q2F0UzZwc3c2V09xYjFUTGpKVjkyd1RTemFML2QyRk0yKzJMNEFuc0tsYzFi?= =?utf-8?B?K2xGL2hSSjQ3UytQOWxndW5wdkRoRzRGa2UrcHNTSkhFQnhENm1pNFdpdEZP?= =?utf-8?B?WmdLVEUyVTlUc0t2bnFWdXVrSTlLSEJ0VGo1b1huQncxZnhwK0YwRnlPTTVo?= =?utf-8?B?V0hISVJtM0pzZU00bC9MLzB4WGw0aWl5Zk1icWVlQnVYc0xHSXRXeXY2dmdk?= =?utf-8?B?cURCN25IUDVGSWl4NVgwUGs1V3NmbDZVUE1mbFM5QXR5RDNMSzJZNjhOaWFJ?= =?utf-8?B?bHFFb3ZHTnJ5NDNZbEJ6VUxoZHR1ZldhWmZZRlVJUTRvMFFtdXlGQVB5QTFw?= =?utf-8?B?T1ZZRGJjK0FyTW04ZWpITTFFaWlXakxGaHBNUkNwdXRnRzJTazBzTEdNbWd4?= =?utf-8?B?TVU3c1JoczA0OXduTzlScGkwcWRFRnJITG1sZy9WZnVLdE9FL2s0RlViakRq?= =?utf-8?B?ZnR0U3hvQjA5ZDA1U205cC9CazNiQjdYU1IrQ200OEUvZmVwK3RyVTlKSFJ6?= =?utf-8?B?TDlCdzhGYjMzMWtraUhRekdvS0RmNHhPUVJlUVd3MlljcW1Ed0VzSXlxTnRP?= =?utf-8?B?M3BMUUVQNmpwc054SE83dVF0THhHOHRsSCtGaDgrMVdCdE15bHZZanZkOXhv?= =?utf-8?B?MW1EOUZhaUVMNFU0VmFPTkM5RyttT1ZMNkc0WUNWMHhnd0tPTGlHRlkvVksy?= =?utf-8?B?SXBieU9wVk0ydkM5RTBlU1FmMnNFWTN0S3EyNG5HcjhWbnhmd0x3cEdaNXFQ?= =?utf-8?B?dmVqNWVzZDFWdE1Gejd5bUM2dXdFaldUbnNjamY3Sm8wMW03WVlZdFNnbkpV?= =?utf-8?B?eGZkUmRUd0tmd0pIckRHRitQQ2xMeUlwNXUvUUt6TjlhU21nM1U0UW5GeFBR?= =?utf-8?B?b0piWnNUampJU2xSVGVWb3p5S0d5MGVGMXc1OHRaNVlrRTlmaitOaTN4TjA4?= =?utf-8?B?SC9iMWxyU2FFZzNHZlFJK2EzRFE1SzBPOS9IRFFHckt4K3k3SW45Y284SFVR?= =?utf-8?B?K3U1Z1VVSjd3bGpXTCtPemFnT2FzYzh5UFlNbEtBZEhDa29mV2JBTHBLdkxG?= =?utf-8?B?TlY3RGZWdFhPcTVjNTY5ZFpadW1jcW9Ic0JKY1FQUXFQdzl5V0JhTU50VTg1?= =?utf-8?B?Q1pUSGxYKy82M1dsQ09oUEI0ejNLNzNZQ1JhUjhXalNHZUQ0Tnp0cjlySjZ5?= =?utf-8?B?ek5oT1htYUtZQTlzV2owb1IxclVlRllpaW9UOHJiUXhYSEpyMEUzaDR2MDVJ?= =?utf-8?B?ajFBMFpvL3MxL3JxbjIyNUVyeEpLNWNlVDJmUVVzSHIwbHRCWWd5WlQwV1l2?= =?utf-8?B?YnMzWm0vQWRYTU1XSjlFbTdSWlE1NDA2MXpUbnpneFk5U3p1V21MKzRzekY2?= =?utf-8?B?OGgvdGZIOGJrN3BvNS9VNC9mOW5OcStncVd5V3FldmZ2MWFkMThWYmg3MnV0?= =?utf-8?B?OFVhUnFDSWJoQ0JGWEgvaEJJWlVxRnVIdmZoMzZacEF2U3BVSHN6SVlnU2RQ?= =?utf-8?B?SDNIWlN6UHNUOWUyY1I3NjA3S3RBaFphaVhWbWNhWFpZWllveHNEaVFveVdO?= =?utf-8?B?R2V6K3BZOE1LMFhxUGt6M3UyeitoenVBY1RkSWExSTFXVkN6Q2JVOW1JNUor?= =?utf-8?B?cW8zUkxuWDU2Ylo0dm5lcUdBdzhPcjFNUWdJS2RnTGFjcXdYTTFpclpRa0JE?= =?utf-8?B?czV2emI5NUN6dlhwdUtNVTFkdlJSa0F4VEljMHJTeHlURmNBYXZ2LytaSmEz?= =?utf-8?B?TmJUeUZvem5oMXZaRzZEMnROSy9TMXBWTFhIRWZmOE1YYnNKTXVrVWtQSlpr?= =?utf-8?Q?VI6eEJztAQruVNNjjW?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b2fcf86a-b14a-4a53-11e7-08dedc67202c X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Jul 2026 20:34:21.4897 (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: 3+nkr1RqBozXXAPuCyoShc+LLp3DM0BK0hHgrZ4bAgbkWlQxEk1iKwkdU6SZ3L2p X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN6PR12MB8591 On Tue Jul 7, 2026 at 9:45 AM EDT, Usama Arif wrote: > queue_folios_pmd() is called under pmd_trans_huge_lock(), whose > pmd_is_huge() check returns true for any non-present, non-none huge > PMD - including a device-private swap entry. Passing such a PMD to > pmd_folio() extracts garbage bits as a PFN and returns a bogus folio > pointer. > > Potential trigger: an HMM-based GPU driver migrates an anonymous THP > folio to device memory via migrate_vma_pages(), leaving a device-private > PMD. Userspace then calls mbind(), migrate_pages() or > set_mempolicy_home_node() on that range. > > Skip device-private PMDs, matching how queue_folios_pte_range() skips > device-private PTE entries by checking !pte_present(). > > Reported-by: sashiko-bot > Link: https://sashiko.dev/#/patchset/20260703173903.3789516-1-usama.arif%= 40linux.dev?part=3D6 > Fixes: 368076f52ebe ("mm/huge_memory: add device-private THP support to P= MD operations") > Signed-off-by: Usama Arif > --- > mm/mempolicy.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index 914f81863db5..eda817539c77 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -659,6 +659,8 @@ static void queue_folios_pmd(pmd_t *pmd, struct mm_wa= lk *walk) > qp->nr_failed++; > return; > } > + if (unlikely(pmd_is_device_private_entry(*pmd))) > + return; Should it also increase qp->nr_failed like pmd migration entry above? It also applies to your "if (unlikely(pmd_is_swap_entry(*pmd)))" in the PMD-level swap patchset. In addition, since pmd_is_huge() returns true for all non-present non-none pmds, other softleaf entries should also be excluded here? Oh, because there is no PMD level hwpoison or pmd marker. --=20 Best Regards, Yan, Zi