Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73023C433EF for ; Tue, 7 Dec 2021 16:37:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233181AbhLGQkg (ORCPT ); Tue, 7 Dec 2021 11:40:36 -0500 Received: from smtp-out2.suse.de ([195.135.220.29]:50506 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229695AbhLGQke (ORCPT ); Tue, 7 Dec 2021 11:40:34 -0500 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 8C67B1FE00; Tue, 7 Dec 2021 16:37:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1638895023; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=t9RUC2PhV3f3vpLr11mqtR46jAj5ypI8WeQwEBxBuSg=; b=nFAtzgaui7XXCSyIUUC0UwS92t88o7kHrBhmYfbaShb0VuaqvjaVvqshjcMYZjZFAiekzn gAYJSC1u5tFGyVtcv44rg12z3kno9uDMQZ4JUqd5e7hAUJbK4tTcMcEfvfX8EiGclUcg/S e75pdfB0GAi2ctXqz6kXWUxR9/t0F9E= Received: from suse.cz (unknown [10.100.201.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 51811A3BA5; Tue, 7 Dec 2021 16:37:03 +0000 (UTC) Date: Tue, 7 Dec 2021 17:36:59 +0100 From: Michal Hocko To: David Hildenbrand Cc: Alexey Makhalov , Dennis Zhou , Eric Dumazet , "linux-mm@kvack.org" , Andrew Morton , Oscar Salvador , Tejun Heo , Christoph Lameter , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: Re: [PATCH v3] mm: fix panic in __alloc_pages Message-ID: References: <1043a1a4-b7f2-8730-d192-7cab9f15ee24@redhat.com> <77e785e6-cf34-0cff-26a5-852d3786a9b8@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 07-12-21 17:27:29, Michal Hocko wrote: [...] > So your proposal is to drop set_node_online from the patch and add it as > a separate one which handles > - sysfs part (i.e. do not register a node which doesn't span a > physical address space) > - hotplug side of (drop the pgd allocation, register node lazily > when a first memblocks are registered) In other words, the first stage diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c5952749ad40..f9024ba09c53 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6382,7 +6382,11 @@ static void __build_all_zonelists(void *data) if (self && !node_online(self->node_id)) { build_zonelists(self); } else { - for_each_online_node(nid) { + /* + * All possible nodes have pgdat preallocated + * free_area_init + */ + for_each_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); build_zonelists(pgdat); @@ -8032,8 +8036,24 @@ void __init free_area_init(unsigned long *max_zone_pfn) /* Initialise every node */ mminit_verify_pageflags_layout(); setup_nr_node_ids(); - for_each_online_node(nid) { - pg_data_t *pgdat = NODE_DATA(nid); + for_each_node(nid) { + pg_data_t *pgdat; + + if (!node_online(nid)) { + pr_warn("Node %d uninitialized by the platform. Please report with boot dmesg.\n", nid); + pgdat = arch_alloc_nodedata(nid); + pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); + arch_refresh_nodedata(nid, pgdat); + free_area_init_memoryless_node(nid); + /* + * not marking this node online because we do not want to + * confuse userspace by sysfs files/directories for node + * without any memory attached to it (see topology_init) + */ + continue; + } + + pgdat = NODE_DATA(nid); free_area_init_node(nid); /* Any memory on that node */ -- Michal Hocko SUSE Labs