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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 7F5E4C4741F for ; Thu, 5 Nov 2020 16:16:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19BDC206B7 for ; Thu, 5 Nov 2020 16:16:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="JBloRvyR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729263AbgKEQQQ (ORCPT ); Thu, 5 Nov 2020 11:16:16 -0500 Received: from mx2.suse.de ([195.135.220.15]:47782 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726371AbgKEQQP (ORCPT ); Thu, 5 Nov 2020 11:16:15 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604592974; h=from:from:reply-to:subject:subject: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=lKB3aZJEDbJcd0NY8J24kxMePym/I6vQZWeeO8AULYg=; b=JBloRvyRqCiMl5OOXJ5kCyn53/9fx39/QfWByfv3igJQ+B/f0PhKZCFDZW/NnyBP8dl7+S e+tKRjJ+vCfmjIIaVkWa7TyFtmQOHJfRlzm7v88Z0l0I/CqKfhiVqQn72n2jvgjS2NinRx 0ggbORWaoJKwdW9mCqFwQ7pYzNx0Pxs= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E3506AB4C; Thu, 5 Nov 2020 16:16:13 +0000 (UTC) Date: Thu, 5 Nov 2020 17:16:12 +0100 From: Michal Hocko To: Feng Tang Cc: Vlastimil Babka , Andrew Morton , Johannes Weiner , Matthew Wilcox , Mel Gorman , dave.hansen@intel.com, ying.huang@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 0/2] mm: fix OOMs for binding workloads to movable zone only node Message-ID: <20201105161612.GM21348@dhcp22.suse.cz> References: <20201104075819.GA10052@dhcp22.suse.cz> <20201104084021.GB15700@shbuild999.sh.intel.com> <20201104085343.GA18718@dhcp22.suse.cz> <20201105014028.GA86777@shbuild999.sh.intel.com> <20201105120818.GC21348@dhcp22.suse.cz> <4029c079-b1f3-f290-26b6-a819c52f5200@suse.cz> <20201105125828.GG21348@dhcp22.suse.cz> <20201105130710.GB16525@shbuild999.sh.intel.com> <20201105131245.GH21348@dhcp22.suse.cz> <20201105134305.GA16424@shbuild999.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201105134305.GA16424@shbuild999.sh.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 05-11-20 21:43:05, Feng Tang wrote: > On Thu, Nov 05, 2020 at 02:12:45PM +0100, Michal Hocko wrote: > > On Thu 05-11-20 21:07:10, Feng Tang wrote: > > [...] > > > My debug traces shows it is, and its gfp_mask is 'GFP_KERNEL' > > > > Can you provide the full information please? Which node has been > > requested. Which cpuset the calling process run in and which node has > > the allocation succeeded from? A bare dump_stack without any further > > context is not really helpful. > > I don't have the same platform as the original report, so I simulated > one similar setup (with fakenuma and movablecore), which has 2 memory > nodes: node 0 has DMA0/DMA32/Movable zones, while node 1 has only > Movable zone. With it, I can got the same error and same oom callstack > as the original report (as in the cover-letter). > > The test command is: > # docker run -it --rm --cpuset-mems 1 ubuntu:latest bash -c "grep Mems_allowed /proc/self/status" > > To debug I only added some trace in the __alloc_pages_nodemask(), and > for the callstack which get the page successfully: > > [ 567.510903] Call Trace: > [ 567.510909] dump_stack+0x74/0x9a > [ 567.510910] __alloc_pages_nodemask.cold+0x22/0xe5 > [ 567.510913] alloc_pages_current+0x87/0xe0 > [ 567.510914] __vmalloc_node_range+0x14c/0x240 > [ 567.510918] module_alloc+0x82/0xe0 > [ 567.510921] bpf_jit_alloc_exec+0xe/0x10 > [ 567.510922] bpf_jit_binary_alloc+0x7a/0x120 > [ 567.510925] bpf_int_jit_compile+0x145/0x424 > [ 567.510926] bpf_prog_select_runtime+0xac/0x130 As already said this doesn't really tell much without the additional information. > The incomming parameter nodemask is NULL, and the function will first try the > cpuset nodemask (1 here), and the zoneidx is only granted 2, which makes the > 'ac's preferred zone to be NULL. so it goes into __alloc_pages_slowpath(), > which will first set the nodemask to 'NULL', and this time it got a preferred > zone: zone DMA32 from node 0, following get_page_from_freelist will allocate > one page from that zone. I do not follow. Both hot and slow paths of the allocator set ALLOC_CPUSET or emulate it by mems_allowed when cpusets are nebaled IIRC. This is later enforced in get_page_from_free_list. There are some exceptions when the allocating process can run away from its cpusets - e.g. IRQs, OOM victims and few other cases but definitely not a random allocation. There might be some subtle details that have changed or I might have forgot but -- Michal Hocko SUSE Labs