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 3C0AEC433F5 for ; Mon, 13 Dec 2021 15:06:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239372AbhLMPGg (ORCPT ); Mon, 13 Dec 2021 10:06:36 -0500 Received: from smtp-out2.suse.de ([195.135.220.29]:55912 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231924AbhLMPGe (ORCPT ); Mon, 13 Dec 2021 10:06:34 -0500 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 985F01F3B9; Mon, 13 Dec 2021 15:06:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1639407992; 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=mo0LvTTdCAdYCELtja1WibnDYrDpY4UUg3gYnSLtKHs=; b=Zv5q+rsqvGBcvPNXTC0JYSr5b+BCn+RUcwsHqjHFcdPO8dKSiP1Ro/pxEtzq/mPItUxgXc xXYhrJoSvPPt52OonbLIzk8XN6t8WeGqg3+JhoraV3Hjbtepfq22fi968GfIQH2cxqiC9v gsqwy8wrjljI5ipLw+Xm4mwO/6oFeb0= 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 68C9DA3B8A; Mon, 13 Dec 2021 15:06:32 +0000 (UTC) Date: Mon, 13 Dec 2021 16:06:31 +0100 From: Michal Hocko To: Alexey Makhalov Cc: Dennis Zhou , Eric Dumazet , "linux-mm@kvack.org" , Andrew Morton , David Hildenbrand , Oscar Salvador , Tejun Heo , Christoph Lameter , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , Nico Pache Subject: Re: [PATCH v3] mm: fix panic in __alloc_pages Message-ID: References: <2e191db3-286f-90c6-bf96-3f89891e9926@gmail.com> <5239D699-523C-4F0C-923A-B068E476043E@vmware.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 Thu 09-12-21 11:48:42, Michal Hocko wrote: [...] > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 852041f6be41..2d38a431f62f 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1161,19 +1161,21 @@ static void reset_node_present_pages(pg_data_t *pgdat) > } > > /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ > -static pg_data_t __ref *hotadd_new_pgdat(int nid) > +static pg_data_t __ref *hotadd_init_pgdat(int nid) > { > struct pglist_data *pgdat; > > pgdat = NODE_DATA(nid); > - if (!pgdat) { > - pgdat = arch_alloc_nodedata(nid); > - if (!pgdat) > - return NULL; > > + /* > + * NODE_DATA is preallocated (free_area_init) but its internal > + * state is not allocated completely. Add missing pieces. > + * Completely offline nodes stay around and they just need > + * reintialization. > + */ > + if (!pgdat->per_cpu_nodestats) { > pgdat->per_cpu_nodestats = > alloc_percpu(struct per_cpu_nodestat); > - arch_refresh_nodedata(nid, pgdat); This should really be diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 42211485bcf3..2daa88ce8c80 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1173,7 +1173,7 @@ static pg_data_t __ref *hotadd_init_pgdat(int nid) * Completely offline nodes stay around and they just need * reintialization. */ - if (!pgdat->per_cpu_nodestats) { + if (pgdat->per_cpu_nodestats == &boot_nodestats) { pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); } else { -- Michal Hocko SUSE Labs