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=-5.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT 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 8707AC07E85 for ; Tue, 11 Dec 2018 09:44:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4812120849 for ; Tue, 11 Dec 2018 09:44:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544521480; bh=LBLIIWiO8XCynTxcti8UWM4RBZAAixTIuoRD0k67Ce0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=OWEyVZR3vaAkISr+MQpGCsPdlYW3+uTNB4/H4cBt8gbhMH/4zyT0TROOjvaX8T8rH lAUiKkX4uE3nq/KAlYGqykeJdqxWaAElt9tnw6aVSZlGR0vF38L7wPUNsa8QWDVwkt QSsT2ZNVInLg9vdL5R2TMem/UbbLy44+wHe9Xpqs= DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4812120849 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726200AbeLKJoj (ORCPT ); Tue, 11 Dec 2018 04:44:39 -0500 Received: from mx2.suse.de ([195.135.220.15]:45636 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726085AbeLKJoi (ORCPT ); Tue, 11 Dec 2018 04:44:38 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id EC671AE8A; Tue, 11 Dec 2018 09:44:36 +0000 (UTC) Date: Tue, 11 Dec 2018 10:44:36 +0100 From: Michal Hocko To: Pingfan Liu Cc: Vlastimil Babka , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Mike Rapoport , Bjorn Helgaas , Jonathan Cameron Subject: Re: [PATCH] mm/alloc: fallback to first node if the wanted node offline Message-ID: <20181211094436.GC1286@dhcp22.suse.cz> References: <20181207075322.GS1286@dhcp22.suse.cz> <20181207113044.GB1286@dhcp22.suse.cz> <20181207142240.GC1286@dhcp22.suse.cz> <20181207155627.GG1286@dhcp22.suse.cz> <20181210123738.GN1286@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 11-12-18 16:05:58, Pingfan Liu wrote: > On Mon, Dec 10, 2018 at 8:37 PM Michal Hocko wrote: > > > > On Fri 07-12-18 16:56:27, Michal Hocko wrote: > > > On Fri 07-12-18 22:27:13, Pingfan Liu wrote: > > > [...] > > > > diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c > > > > index 1308f54..4dc497d 100644 > > > > --- a/arch/x86/mm/numa.c > > > > +++ b/arch/x86/mm/numa.c > > > > @@ -754,18 +754,23 @@ void __init init_cpu_to_node(void) > > > > { > > > > int cpu; > > > > u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid); > > > > + int node, nr; > > > > > > > > BUG_ON(cpu_to_apicid == NULL); > > > > + nr = cpumask_weight(cpu_possible_mask); > > > > + > > > > + /* bring up all possible node, since dev->numa_node */ > > > > + //should check acpi works for node possible, > > > > + for_each_node(node) > > > > + if (!node_online(node)) > > > > + init_memory_less_node(node); > > > > > > I suspect there is no change if you replace for_each_node by > > > for_each_node_mask(nid, node_possible_map) > > > > > > here. If that is the case then we are probably calling > > > free_area_init_node too early. I do not see it yet though. > > > > OK, so it is not about calling it late or soon. It is just that > > node_possible_map is a misnomer and it has a different semantic than > > I've expected. numa_nodemask_from_meminfo simply considers only nodes > > with some memory. So my patch didn't really make any difference and the > > node stayed uninialized. > > > > In other words. Does the following work? I am sorry to wildguess this > > way but I am not able to recreate your setups to play with this myself. > > > No problem. Yeah, in order to debug the patch, you need a numa machine > with a memory-less node. And unlucky, the patch can not work either by > grub bootup or kexec -l boot. There is nothing, just silent. I will > dig into numa_register_memblks() to figure out the problem. I do not have such a machine handy. Anyway, can you post the full serial console log. Maybe I can infer something. It is quite weird that this patch would make an existing situation any worse. -- Michal Hocko SUSE Labs