From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 0FBDF3BC677; Mon, 13 Apr 2026 15:21:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776093679; cv=none; b=sqW31hzdNx/Z3QY1088azF37BA9z2owZLFyKt9TRZ5xtDJovl6ELkg3HZEsNZP0dSg2uBj3bW93hj3eDLkj5JpfQttH1RJEoZ4CtpImgzIdPuW1UOHM6v4pHiUcSHHPx6XP617iZFl63hVkb/2VRiDJmi5IfSY7DCX5WCXJlSGw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776093679; c=relaxed/simple; bh=0tDU+gJ0igRYGEMqvw+y8S5RV0mbZpxGXNcPCdzGa7M=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Y+9wjXDlSal034Ms8iObK1UmpcHs2iX4bZ6BBIvAaN7ru88STLLCkKCdjlwi0b+lOFcybWXXeOB6dVGlSyU4I5vOSIsvVuITVFN1ruQsVk0PoJx5LAbZe++YlVNzBx8BvBq1aEAUHekwXZZWxgoqrK8AUJN/FWeRSgsWIFDEnys= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M6z5tz8k; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="M6z5tz8k" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1EFBC2BCAF; Mon, 13 Apr 2026 15:21:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776093678; bh=0tDU+gJ0igRYGEMqvw+y8S5RV0mbZpxGXNcPCdzGa7M=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=M6z5tz8kY/PU01R6WlDxuIBLJ/bJKpoQAnN5/1qbP5spDN/iPHFfPzBLX8mkV9DDA G3DkT5bVzg5U94Px2HUhWXhaFgUi7LQGLGjQ1MGNP2Hg7lQ00dASwHNXXyav63gc+O QJw4wroV76SWun3igUHrJLnRhHd5ncUMOZRcUV7H57gEbsMQRAPHz0ozkufzm0xY7j GLOQM9DkBLKmLeoBhWTfOczfcajffXg2kORKsS/ddCSJDfF4e+5gR9FvsqS1/3omX0 fLaDhmGnEfXD2Oms09iM24cDcFoNNVmfzLMASw49qqzsjfZ+0MssJoXaRE3ZQseoyK oYUbhyfDTuhEA== Message-ID: Date: Mon, 13 Apr 2026 17:21:11 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 5/8] mm/memory_hotplug: add __add_memory_driver_managed() with online_type arg To: Gregory Price , linux-mm@kvack.org, vishal.l.verma@intel.com, dave.jiang@intel.com, akpm@linux-foundation.org, osalvador@suse.de Cc: dan.j.williams@intel.com, ljs@kernel.org, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, kernel-team@meta.com References: <20260321150404.3288786-1-gourry@gourry.net> <20260321150404.3288786-6-gourry@gourry.net> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/21/26 16:04, Gregory Price wrote: > Existing callers of add_memory_driver_managed cannot select the > preferred online type (ZONE_NORMAL vs ZONE_MOVABLE), requiring it to > hot-add memory as offline blocks, and then follow up by onlining each > memory block individually. > > Most drivers prefer the system default, but the CXL driver wants to > plumb a preferred policy through the dax kmem driver. > > Refactor APIs to add a new interface which allows the dax kmem and > cxl_core modules to select a preferred policy. Only expose this > interface to those modules to avoid confusion among existing API users > and to limit usage in out-of-tree modules. > > Refactor add_memory_driver_managed, extract __add_memory_driver_managed > - Add proper kernel-doc for add_memory_driver_managed while refactoring > - New helper accepts an explicit online_type. > - New help validates online_type is between OFFLINE and ONLINE_MOVABLE > > Refactor: add_memory_resource, extract __add_memory_resource > - new helper accepts an explicit online_type > > Original APIs now explicitly pass the system-default to new helpers. > > No functional change for existing users. > You should add here, that we only allow known in-tree modules to overwrite the onlining policy (where we know that it's a different user-requested policy), as we don't want arbitrary OOT drivers to overwrite the configured system policy. Therefore EXPORT_SYMBOL_FOR_MODULES(). Acked-by: David Hildenbrand (Arm) -- Cheers, David