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=-4.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 4202DC04EB8 for ; Thu, 6 Dec 2018 07:24:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03BE020989 for ; Thu, 6 Dec 2018 07:24:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544081043; bh=aRHlMzdx8XH730nvmXkChwgIkpst1s2bSdJKmbZSKrg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=fYKatQHSDBJYTtRrlVy69bkb36lijal+0tD0pGru7D5wvaCuL9/qGwZ3dlyLxRYr7 7GEkZn3rsH375RaQXPIUl53Xk/KU2HOIZUYwjC9Ly4kKkSQ5kW+IvI6guJlKdyKWXs 8yikMh6/tc/Wz4ZCwwgbHovTkFqh2ik+ZjBJGKkI= DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 03BE020989 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 S1729136AbeLFHYB (ORCPT ); Thu, 6 Dec 2018 02:24:01 -0500 Received: from mx2.suse.de ([195.135.220.15]:33560 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728294AbeLFHYB (ORCPT ); Thu, 6 Dec 2018 02:24:01 -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 94044AE66; Thu, 6 Dec 2018 07:23:59 +0000 (UTC) Date: Thu, 6 Dec 2018 08:23:57 +0100 From: Michal Hocko To: Pingfan Liu Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Vlastimil Babka , Mike Rapoport , Bjorn Helgaas , Jonathan Cameron , "Rafael J. Wysocki" , Len Brown , linux-acpi@vger.kernel.org Subject: Re: [PATCH] mm/alloc: fallback to first node if the wanted node offline Message-ID: <20181206072357.GA1286@dhcp22.suse.cz> References: <1543892757-4323-1-git-send-email-kernelfans@gmail.com> <20181204072251.GT31738@dhcp22.suse.cz> <20181204085601.GC1286@dhcp22.suse.cz> <20181205092148.GA1286@dhcp22.suse.cz> <20181205094327.GD1286@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 Thu 06-12-18 11:34:30, Pingfan Liu wrote: [...] > > I suspect we are looking at two issues here. The first one, and a more > > important one is that there is a NUMA affinity configured for the device > > to a non-existing node. The second one is that nr_cpus affects > > initialization of possible nodes. > > The dev->numa_node info is extracted from acpi table, not depends on > the instance of numa-node, which may be limited by nr_cpus. Hence the > node is existing, just not instanced. Hmm, binding to memory less node is quite dubious. But OK. I am not sure how much sanitization can we do. We need to fallback anyway so we should better make sure that all possible nodes are initialized regardless of nr_cpus. I will look into that. -- Michal Hocko SUSE Labs