From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-f199.google.com (mail-pg1-f199.google.com [209.85.215.199]) by kanga.kvack.org (Postfix) with ESMTP id 7539B8E0097 for ; Thu, 24 Jan 2019 14:10:52 -0500 (EST) Received: by mail-pg1-f199.google.com with SMTP id s22so4565841pgv.8 for ; Thu, 24 Jan 2019 11:10:52 -0800 (PST) Received: from mga01.intel.com (mga01.intel.com. [192.55.52.88]) by mx.google.com with ESMTPS id z20si21527519pgv.159.2019.01.24.11.10.50 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Jan 2019 11:10:51 -0800 (PST) Subject: Re: [RFC PATCH] x86, numa: always initialize all possible nodes References: <20190114082416.30939-1-mhocko@kernel.org> <20190124141727.GN4087@dhcp22.suse.cz> From: Dave Hansen Message-ID: <3a7a3cf2-b7d9-719e-85b0-352be49a6d0f@intel.com> Date: Thu, 24 Jan 2019 11:10:50 -0800 MIME-Version: 1.0 In-Reply-To: <20190124141727.GN4087@dhcp22.suse.cz> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko , linux-mm@kvack.org Cc: Pingfan Liu , Peter Zijlstra , x86@kernel.org, Benjamin Herrenschmidt , Michael Ellerman , Tony Luck , linuxppc-dev@lists.ozlabs.org, linux-ia64@vger.kernel.org, LKML On 1/24/19 6:17 AM, Michal Hocko wrote: > and nr_cpus set to 4. The underlying reason is tha the device is bound > to node 2 which doesn't have any memory and init_cpu_to_node only > initializes memory-less nodes for possible cpus which nr_cpus restrics. > This in turn means that proper zonelists are not allocated and the page > allocator blows up. This looks OK to me. Could we add a few DEBUG_VM checks that *look* for these invalid zonelists? Or, would our existing list debugging have caught this? Basically, is this bug also a sign that we need better debugging around this?