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=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 624AFC49EA5 for ; Fri, 25 Jun 2021 02:29:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 41BCC61375 for ; Fri, 25 Jun 2021 02:29:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233024AbhFYCbq (ORCPT ); Thu, 24 Jun 2021 22:31:46 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:33871 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232942AbhFYCbo (ORCPT ); Thu, 24 Jun 2021 22:31:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624588164; 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=FL2VYICYfZ174jQ2nGIPRQennz6mpczdJxUYPljWvaU=; b=M74e1XXl3i00mcfEXgeCiyrl5bpASxLkvAeVf2kX4dR/LEZ9JcLOumiCJgdxeX+pN4c1oo 0yn2sn2uFBDmxzodYUkpJkzr0tZyYK3JvYygFBGYEp2snXhGRrTBAKGC33/T5dDR2c4fGf nrtWvzyYuRX9xQ5Dqxjce+eY6eU7nF4= 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-588-AmYwe0VSPpud6YGyVqoUdg-1; Thu, 24 Jun 2021 22:29:22 -0400 X-MC-Unique: AmYwe0VSPpud6YGyVqoUdg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 990CF362FD; Fri, 25 Jun 2021 02:29:21 +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 A87BB5D6AB; Fri, 25 Jun 2021 02:29:16 +0000 (UTC) From: Gavin Shan To: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, rdunlap@infradead.org, robh+dt@kernel.org, drjones@redhat.com, shan.gavin@gmail.com Subject: [PATCH v3] Documentation, dt, numa: Add note to empty NUMA node Date: Fri, 25 Jun 2021 12:30:25 +0800 Message-Id: <20210625043025.47469-1-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 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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..edf728cff155 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