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 5C274392808; Thu, 22 Jan 2026 21:28:08 +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=1769117289; cv=none; b=M49jS+IqlnnizKHB4Yo2KrGovdbUuprdLB88imFv/0ZX5SUCvx/O0v0tnWGGLA/PGn4FsZon9Yub8zK6TBpXHg/oGJMDQX66Aw9B91wDB2RkgGKRLh7IcpmO85JoPFlcyv39A6zbcz5JU6XcrcRog+sLAwH3vYdMTfNDfT6w1yo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769117289; c=relaxed/simple; bh=knqv3YaYhXLjzVaLE6iKL0LxzIm/k75UNIsgiKoIlIU=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=QWmAb47HN/1LHQgvLKydxiTG+iuNdhWhRd/Vxxp7lqU6BA5vFY5KPxIX1m9Xy1HEBunuwKcdSDoQ7DsghdN1A/DYZm7WUEa69Mj3mjfzPsWh51DCuqOZEdlcRncERfhMnQVyYvQV5L44A2wjQC8Vj3xg3OprC8VofOKfNClSv8o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=13YXjGm8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="13YXjGm8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36606C116C6; Thu, 22 Jan 2026 21:28:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1769117288; bh=knqv3YaYhXLjzVaLE6iKL0LxzIm/k75UNIsgiKoIlIU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=13YXjGm8umxmJamt0Zl1nKi6FNc3yziP/vjSEGG91+vsNi4OogHLRxY7Os18riT6j xSB1wtQTgLsp2E+D4CjtXNYBRWoJb6FbDoLA75BqLwuEZ73BxJni5ECzExUPT4C57K NjFDS57rLQ2ZgcD+FsaZEXwed9MX9I3E9DrRSicA= Date: Thu, 22 Jan 2026 13:28:07 -0800 From: Andrew Morton To: Cui Chao Cc: dan.j.williams@intel.com, Jonathan Cameron , Mike Rapoport , Wang Yinfeng , linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2 1/1] mm: numa_memblks: Identify the accurate NUMA ID of CFMW Message-Id: <20260122132807.7204b83e97e33290f6eb7d82@linux-foundation.org> In-Reply-To: <2d1e23ad-7ec1-483b-88b3-70ce19b69106@phytium.com.cn> References: <20260106031042.1606729-1-cuichao1753@phytium.com.cn> <20260106031042.1606729-2-cuichao1753@phytium.com.cn> <20260108094812.8757ce3ad8370668eaafb29c@linux-foundation.org> <9132054c-3017-4af0-84e0-e4359b0794a6@phytium.com.cn> <20260115101858.85fd7b8e837c1c92a4fdc5f0@linux-foundation.org> <696944eca1837_34d2a10056@dwillia2-mobl4.notmuch> <2d1e23ad-7ec1-483b-88b3-70ce19b69106@phytium.com.cn> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 22 Jan 2026 16:03:49 +0800 Cui Chao wrote: > > >> So please, tell us how much our users are hurting from this and please > >> make a recommendation on the backporting decision. > >> > > To add on here, Cui, please describe which shipping hardware platforms > > in the wild create physical address maps like this. For example, if this > > is something that only occurs in QEMU configurations or similar, then > > the urgency is low and it is debatable if Linux should even worry about > > fixing it. > > > > I know that x86 platforms typically do not do this. It is also > > within the realm of possibility for platform firmware to fix. So in > > addition to platform impact please also clarify why folks can not just > > ask for a firmware update to get this fixed without updating their > > kernel. > > Andrew, Dan, thank you for your review. > > 1.Issue Impact and Backport Recommendation: > > ... > > Thus, I believe a kernel fix is necessary. Thanks, I posted all that into the changelog. > Therefore, I recommend backporting this patch to all stable kernel > series that support dynamic CXL region creation. It's helpful if we can tell -stable maintainers which kernel versions "support dynamic CXL region creation". We communicate that by providing a Fixes: tag in the changelog. Are you able to help identify a suitable commit for this?