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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 373ECC48BC2 for ; Thu, 24 Jun 2021 01:36:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1AEDB6137D for ; Thu, 24 Jun 2021 01:36:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229774AbhFXBih (ORCPT ); Wed, 23 Jun 2021 21:38:37 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:59495 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229831AbhFXBih (ORCPT ); Wed, 23 Jun 2021 21:38:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624498578; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=MWyyy9NSRWYF/IIOd9RfJwjKp0KmO/I0ymT6gR07HiY=; b=VZYa00ddQ1OjZUlWIwpD5PNLITk5Z+I+BHTK9yS3kLFiA4hLiXb4RJ+A5V3gHFco+9lxid 33l8PQYXe9HKcH1y5XBEOO0HYfDT9ZSwVxcjlnhSGWQLANGaWCR+gpr3aad0OSwxrZJAMR FdI1s53un77Zv9cLY2d/8Mm+DhSCHEQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-46-O8Z27GltM5Wg0YAVBsHl6w-1; Wed, 23 Jun 2021 21:36:17 -0400 X-MC-Unique: O8Z27GltM5Wg0YAVBsHl6w-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2BA741084F53; Thu, 24 Jun 2021 01:36:16 +0000 (UTC) Received: from gshan.redhat.com (vpn2-54-70.bne.redhat.com [10.64.54.70]) by smtp.corp.redhat.com (Postfix) with ESMTP id B4EA85D9C6; Thu, 24 Jun 2021 01:36:14 +0000 (UTC) From: Gavin Shan To: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, robh+dt@kernel.org, drjones@redhat.com, shan.gavin@gmail.com Subject: [PATCH] Documentation, dt, numa: Add note to empty NUMA node Date: Thu, 24 Jun 2021 11:37:40 +0800 Message-Id: <20210624033740.20862-1-gshan@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The empty NUMA nodes, where no memory resides in, are allowed. For these empty NUMA nodes, the 'len' of 'reg' property is zero. These empty NUMA node IDs are still valid and parsed. I finds difficulty to get where it's properly documented. So lets add note to empty NUMA nodes in the NUMA binding doc. Signed-off-by: Gavin Shan --- 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..c564705c0eac 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 the empty NUMA nodes, which no memory resides in, are allowed +Their NUMA node IDs are still valid so that memory can be added into these +NUMA nodes through hotplug afterwards. + memory@c00000 { device_type = "memory"; reg = <0x0 0xc00000 0x0 0x80000000>; -- 2.23.0