From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936068Ab3DICFa (ORCPT ); Mon, 8 Apr 2013 22:05:30 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:3690 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751100Ab3DICF3 (ORCPT ); Mon, 8 Apr 2013 22:05:29 -0400 X-IronPort-AV: E=Sophos;i="4.87,435,1363104000"; d="scan'208";a="7018126" Message-ID: <516377CF.2080004@cn.fujitsu.com> Date: Tue, 09 Apr 2013 10:07:11 +0800 From: Lin Feng User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Will Deacon CC: "akpm@linux-foundation.org" , "cl@linux.com" , "tglx@linutronix.de" , "mingo@redhat.com" , "hpa@zytor.com" , "yinghai@kernel.org" , Catalin Marinas , "arnd@arndb.de" , "tony@atomide.com" , "ben@decadent.org.uk" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , "linux-mm@kvack.org" , "isimatu.yasuaki@jp.fujitsu.com" Subject: Re: [PATCH 2/2] mm: vmemmap: arm64: add vmemmap_verify check for hot-add node case References: <1365415000-10389-1-git-send-email-linfeng@cn.fujitsu.com> <1365415000-10389-3-git-send-email-linfeng@cn.fujitsu.com> <20130408105556.GB17476@mudshark.cambridge.arm.com> In-Reply-To: <20130408105556.GB17476@mudshark.cambridge.arm.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/04/09 10:04:15, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/04/09 10:04:19, Serialize complete at 2013/04/09 10:04:19 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi will, On 04/08/2013 06:55 PM, Will Deacon wrote: > Given that we don't have NUMA support or memory-hotplug on arm64 yet, I'm > not sure that this change makes much sense at the moment. early_pfn_to_nid > will always return 0 and we only ever have one node. > > To be honest, I'm not sure what that vmemmap_verify check is trying to > achieve anyway. ia64 does some funky node affinity initialisation early on > but, for the rest of us, it looks like we always just check the distance > from node 0. Sorry for my noise to arm people. Yes, not everyone cares about vmemmap_verify(), as you described it's not necessary to arm64 at all. thanks, linfeng