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 3848B19CD1D; Tue, 27 Jan 2026 23:06:08 +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=1769555168; cv=none; b=Hi9E6/xnkdMSvbnI0vMic9T7t/Rzwt/zm7aBN/xmaRZu54yIWmgZpLmDIE0KQ40mRDQvotMYcc6OVy4aVS76Eb5qrvqUwxuAMW3eugwgM97ew+dLkmo7raESj6232ZePygc9RWsLhjAC+hIMBem8P7GaUmZ3pTvItWPLFkUlaRQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769555168; c=relaxed/simple; bh=GZx2go61irl/yrU3n13wEmtTxxomni09R+ySI530Rio=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=tlEw7toCcWFDyvU0G7EcdIVP5jXbX1DrYld7TwlLiapg2euD5w3Um55iW0wlgK+6EGAdvkor2r4iBcFsTh2+3GRGggFmFLWmf42OsVMwq7r73L/RUSUQ+TYRrQBFG0R0Atr5j6360CULtmLvfFt2Kcdh2zLse4IK9BBfLm5h/1M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lbORS222; 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="lbORS222" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6B3E1C116C6; Tue, 27 Jan 2026 23:06:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769555168; bh=GZx2go61irl/yrU3n13wEmtTxxomni09R+ySI530Rio=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=lbORS2221mW4UB7Lc78M075DHdbfBzuAOnIJOGnqtOVAb1UBVbld5xFTahgT2k+4y xyOEhvem8/S2x+iQxNzPgoRodqPGLzza1t781oLP2BVOdW8so6NHogSdOSZp4nOL9V aIzFDiQ8s0swPdHCwrDK9jiCJrAm7jeoXWKv42pOcvPGRACH1HX4BLqyro+ASH+LL8 mo9mDnsMMorr9I86BPO77e4aMCdK6YPxhZttnWgwTL8ETXBSzs5KCqFtVq9hFZp3XP d9+/vnbUvZWv91I7tfhhBFSKcihw4RepYQXh/3Aex++BEDr4q2uNSi5JLiMwybcI5n RzEMzYINQ/Fkw== Message-ID: <793fb531-1fda-4de4-b73f-fb46444ca613@kernel.org> Date: Wed, 28 Jan 2026 00:06:01 +0100 Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/8] mm/memory_hotplug: add APIs for explicit online type control To: Gregory Price , Jonathan Cameron Cc: linux-mm@kvack.org, linux-cxl@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, virtualization@lists.linux.dev, kernel-team@meta.com, dan.j.williams@intel.com, vishal.l.verma@intel.com, dave.jiang@intel.com, mst@redhat.com, jasowang@redhat.com, xuanzhuo@linux.alibaba.com, eperezma@redhat.com, osalvador@suse.de, akpm@linux-foundation.org References: <20260114085201.3222597-1-gourry@gourry.net> <20260114085201.3222597-4-gourry@gourry.net> <4520e7b0-8218-404d-8ede-e62d95c50825@kernel.org> <20260123182526.00005ee8@huawei.com> From: "David Hildenbrand (Red Hat)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/23/26 20:12, Gregory Price wrote: > On Fri, Jan 23, 2026 at 06:25:26PM +0000, Jonathan Cameron wrote: >> On Thu, 22 Jan 2026 19:34:10 -0500 >> Gregory Price wrote: >> >>> >>> Ah, this was lost on me. >>> >>> >>> unclear to me how to restrict a function to specific drivers, but i can >>> add add_and_online_memory_driver_managed() trivially so no big issue. >> >> Is EXPORT_SYMBOL_GPL_FOR_MODULE() enough? It's also fine for me to just limit add_memory_driver_managed() to in-tree driver by using EXPORT_SYMBOL_FOR_MODULES. But it might make nvidia unhappy :) So maybe just adding a __add_memory_driver_managed() that gives us more control and using EXPORT_SYMBOL_FOR_MODULES is being a bit nicer for OOT modules. (I guess __add_memory_driver_managed is a better name than add_and_online_memory_driver_managed, thinking about it) >> > > Is the issue just that add_memory_driver_manage is `extern`? Heh, the "extern" is simply not necessary and can be dropped from all such functions. Not related to this. It's all about EXPORT_SYMBOL_GPL allowing anything that claims to be a GPL module to use this functionality. > If so > yeah, i can just do the EXPORT_*_GPL path. > > If you prefer FOR_MODULE, then yes I can do this. I'd go for EXPORT_SYMBOL_FOR_MODULES(__add_memory_driver_managed, "dax") (or would it be the kmem module?) -- Cheers David