From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D6AEC48BC2 for ; Fri, 25 Jun 2021 05:29:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82D0C6140C for ; Fri, 25 Jun 2021 05:29:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233125AbhFYFbs (ORCPT ); Fri, 25 Jun 2021 01:31:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48412 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229458AbhFYFbq (ORCPT ); Fri, 25 Jun 2021 01:31:46 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7248BC061574; Thu, 24 Jun 2021 22:29:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description; bh=cLC98jiTPo1gha2IvZDXk9+JdpFRGnaI/CVGtq7Uo10=; b=VIfRY38T8ObhjQYAl4bld7vSFW WiE8Bveu99uFFz5keRNKhvsD1IZ/0YAledCW4anb30got1YzBhmtrN8SXCp+f8rqgz+gDTePEBaX1 UQPy06n9v9shcCAEGQFTn/w24gNMd/n5vATugZEbKsgcUlA6bE+FGhFRpRGPktQOPx5bxA2Ew7B80 2DJVEeDqHwnMRR68ZoT59LxqgudH5SyUzCJRuncwidyiwQIbG2gFGvUIGlqjdMeUDg3UGkHXO6bVl sYlljlvb5GOWDJZWVbbYHSogdVFbLXdL4DQdOEk0tZbfobdZ6L5/ygTcVR8raivaF2EAWrOOtMm1T eopo0KRA==; Received: from [2601:1c0:6280:3f0::aefb] by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1lweP5-00HJQu-AJ; Fri, 25 Jun 2021 05:29:23 +0000 Subject: Re: [PATCH v4] Documentation, dt, numa: Add note to empty NUMA node To: Gavin Shan , devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, robh+dt@kernel.org, drjones@redhat.com, shan.gavin@gmail.com References: <20210625052338.4875-1-gshan@redhat.com> From: Randy Dunlap Message-ID: <7cdbafb8-4c38-1aac-5362-25e27e1d13e4@infradead.org> Date: Thu, 24 Jun 2021 22:29:22 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210625052338.4875-1-gshan@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/24/21 10:23 PM, Gavin Shan wrote: > The empty memory nodes, where no memory resides in, are allowed. > For these empty memory nodes, the 'len' of 'reg' property is zero. > The NUMA node IDs are still valid and parsed, but memory can be > added to them through hotplug afterwards. I finds difficulty to > get where it's properly documented. > > So lets add note to empty memory nodes in the NUMA binding doc. > > Signed-off-by: Gavin Shan Acked-by: Randy Dunlap Thanks. > --- > Documentation/devicetree/bindings/numa.txt | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/devicetree/bindings/numa.txt b/Documentation/devicetree/bindings/numa.txt > index 21b35053ca5a..0fc882e44270 100644 > --- a/Documentation/devicetree/bindings/numa.txt > +++ b/Documentation/devicetree/bindings/numa.txt > @@ -109,6 +109,10 @@ Example: > Dual socket system consists of 2 boards connected through ccn bus and > each board having one socket/soc of 8 cpus, memory and pci bus. > > +Note that empty memory nodes, which no memory resides in, are allowed. > +The NUMA node IDs in these empty memory nodes are still valid, but > +memory can be added into them through hotplug afterwards. > + > memory@c00000 { > device_type = "memory"; > reg = <0x0 0xc00000 0x0 0x80000000>; >