From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from DM1PR04CU001.outbound.protection.outlook.com (mail-centralusazon11010050.outbound.protection.outlook.com [52.101.61.50]) (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 75DA92475C8; Tue, 30 Sep 2025 04:04:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.61.50 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759205089; cv=fail; b=F/yC+YZVdQmk6mWJTkfe10W22Ug8mn/G9HpGnKv0pMbQQxmucazOHoVCTV0DrO6FyyvnOVPU7Yqf2GRzYQ7y9e1q0YBtMcUXsKrUdlV203WK7gp1NO3uQPuYu8DJTXAdZ+64H9dkAUjEKaZYHD4Tj2RraV15iJX4tMUV9XPqT7Y= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759205089; c=relaxed/simple; bh=T6WLO1YO4VBshilAd/fvSVYkR5QY23QQhZgIutlhy34=; h=Message-ID:Date:From:Subject:To:Cc:References:In-Reply-To: Content-Type:MIME-Version; b=D92QSSeyMN371UnmpCFUZe4V0lpACGGTNNBDfWT40V8r9Wn+CcBlq0zzz+S2IIMkTu2EEnUHEhdc1I7jjAuEM0EqLp0518KgSeaiVrZJA6uYztd8Xx57FsoblNdAnoE4c52N3HU/dl2HllPdjYn0/NrqxVADsS4Sdu4Zjr0+Jho= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=uoin9hVX; arc=fail smtp.client-ip=52.101.61.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="uoin9hVX" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=ekbaeRVv26DcXfD+d2rBbYmyIv1SyXS99ZdT6c3jhJwaYZa35Tu8t6RPMF6tOpwr9In8+LxOHzH517vot+wOX8sJwTYVIJJw7qjMkH0ani2k6bj0Gt27tWNrWU7hv50oi6bK+FH3zjq1gzl8+Nvaeop3L2mh5IOvN/2hbY67Y6FrTtdFKVQgDLqIAjOKbhZMgg8yH9w3FL7/3qaRAkUHJZlHiZJun6+IUhQHPp/nGr1eLd+Pqig1gse9Ctc9v4M22rLZlgWHuq1VqJUQEPYjDfsfmW81pMVULeKK002gMPRhhe6sXY+1akbw7fSr9GL7gNPSSOgsSBZqaPTeYdAPyA== 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=rMeDY8jA3RW4qFNK9qdhPtmPgZ/td4A648lupxtKiFE=; b=tBEryxnKQVLDaor12UcsFtkcwgFH5SZFrvBYZ7gZumhHauerVBqIQB2JWODB0+23zwkh6QTDACZvAbZGjVlvNqvO+BY/yUrzvQaMpod8PHTognSZ9ItRGRfNwJau+xKDLKPOYQ3LgDQd81+GlAldXK7qFjOa/AkbLGiTv3Tzi1K7Tx3QWGEyQVM64hCFtrGAqHGCPJmRneHULX6PQBrhYCv/LL6IYyi2IqsS0nnePsKePfaiTRTxMmqSfuUDt4WUT19LaZb98JEC4ie/r7Y28dkakob0EmFk29z0kBZpd1LrO1Pk7G1dQmB3Yvn9NzzWoJafnStopOnoqhTkLOhH3Q== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=rMeDY8jA3RW4qFNK9qdhPtmPgZ/td4A648lupxtKiFE=; b=uoin9hVX33beeqj0Z37PnMolFCGnk6nOR12nPJ2Gco3JsMwsc12iUGVG9IQAR3qzLKnUJzUS40nBJ983/K220gaDfp6dOW0fw33HLR7IQrorN25qkPouYW4FWZ9FFSO5lAyeG9YVYuoAGUL58k4FIOIcOucK/EFc9UfY/2Efphg= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from MW4PR12MB7142.namprd12.prod.outlook.com (2603:10b6:303:220::6) by DM4PR12MB8572.namprd12.prod.outlook.com (2603:10b6:8:17d::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9160.17; Tue, 30 Sep 2025 04:04:45 +0000 Received: from MW4PR12MB7142.namprd12.prod.outlook.com ([fe80::e5b2:cd7c:ba7d:4be3]) by MW4PR12MB7142.namprd12.prod.outlook.com ([fe80::e5b2:cd7c:ba7d:4be3%7]) with mapi id 15.20.9160.015; Tue, 30 Sep 2025 04:04:45 +0000 Message-ID: <876c01d5-0b32-4be0-92c7-acfdbf96767b@amd.com> Date: Mon, 29 Sep 2025 21:04:42 -0700 User-Agent: Mozilla Thunderbird From: "Koralahalli Channabasappa, Smita" Subject: Re: [PATCH 3/6] dax/hmem, cxl: Tighten dependencies on DEV_DAX_CXL and dax_hmem To: "Zhijian Li (Fujitsu)" , Smita Koralahalli , "linux-cxl@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "nvdimm@lists.linux.dev" , "linux-fsdevel@vger.kernel.org" , "linux-pm@vger.kernel.org" Cc: Davidlohr Bueso , Jonathan Cameron , Dave Jiang , Alison Schofield , Vishal Verma , Ira Weiny , Dan Williams , Matthew Wilcox , Jan Kara , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Li Ming , Jeff Johnson , Ying Huang , "Xingtao Yao (Fujitsu)" , Peter Zijlstra , Greg KH , Nathan Fontenot , Terry Bowman , Robert Richter , Benjamin Cheatham , PradeepVineshReddy Kodamati References: <20250822034202.26896-1-Smita.KoralahalliChannabasappa@amd.com> <20250822034202.26896-4-Smita.KoralahalliChannabasappa@amd.com> Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SJ0PR03CA0061.namprd03.prod.outlook.com (2603:10b6:a03:331::6) To MW4PR12MB7142.namprd12.prod.outlook.com (2603:10b6:303:220::6) Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MW4PR12MB7142:EE_|DM4PR12MB8572:EE_ X-MS-Office365-Filtering-Correlation-Id: b61d8ef4-075c-4c72-a90c-08ddffd67d50 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|1800799024|366016; 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To clarify, another prerequisite for > this ordering to work correctly is that dax_hmem must explicitly call > `request_module("cxl_acpi")` and `request_module("cxl_pci")` during its initialization. > > Therefore, I recommend consolidating the following patches into a single commit > to ensure atomic handling of the initialization order: > - [PATCH 2/6] dax/hmem: Request cxl_acpi and cxl_pci before walking Soft Reserved ranges > - [PATCH 3/6] dax/hmem, cxl: Tighten dependencies on DEV_DAX_CXL and dax_hmem > > Thanks > Zhijian I have merged 2/6 and 3/6 in v2. Thanks Smita >> This prevents dax_hmem from consuming >> Soft Reserved ranges before CXL drivers have had a chance to claim them. >> >> Replace IS_ENABLED(CONFIG_CXL_REGION) with IS_ENABLED(CONFIG_DEV_DAX_CXL) >> so the code more precisely reflects when CXL-specific DAX coordination is >> expected. >> >> This ensures that ownership of Soft Reserved ranges is consistently >> handed off to the CXL stack when DEV_DAX_CXL is configured.