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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 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 0D077C10F27 for ; Mon, 9 Mar 2020 13:28:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DB1D820727 for ; Mon, 9 Mar 2020 13:28:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726569AbgCIN2B (ORCPT ); Mon, 9 Mar 2020 09:28:01 -0400 Received: from out30-45.freemail.mail.aliyun.com ([115.124.30.45]:36207 "EHLO out30-45.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726659AbgCIN2B (ORCPT ); Mon, 9 Mar 2020 09:28:01 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R691e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04455;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0Ts81o5L_1583760421; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0Ts81o5L_1583760421) by smtp.aliyun-inc.com(127.0.0.1); Mon, 09 Mar 2020 21:27:01 +0800 Subject: Re: linux-next test error: BUG: using __this_cpu_read() in preemptible code in __mod_memcg_state From: Alex Shi To: "Kirill A. Shutemov" , syzbot Cc: akpm@linux-foundation.org, cgroups@vger.kernel.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@kernel.org, syzkaller-bugs@googlegroups.com, vdavydov.dev@gmail.com References: <00000000000022640205a04a20d8@google.com> <20200309092423.2ww3aw6yfyce7yty@box> <5b1196be-09ce-51f7-f5e7-63f2e597f91e@linux.alibaba.com> Message-ID: Date: Mon, 9 Mar 2020 21:26:59 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <5b1196be-09ce-51f7-f5e7-63f2e597f91e@linux.alibaba.com> Content-Type: text/plain; charset=gbk Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2020/3/9 下午5:56, Alex Shi 写道: > > > 在 2020/3/9 下午5:24, Kirill A. Shutemov 写道: >>> check_preemption_disabled: 3 callbacks suppressed >>> BUG: using __this_cpu_read() in preemptible [00000000] code: syz-fuzzer/9432 >>> caller is __mod_memcg_state+0x27/0x1a0 mm/memcontrol.c:689 >>> CPU: 1 PID: 9432 Comm: syz-fuzzer Not tainted 5.6.0-rc4-next-20200306-syzkaller #0 >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 >>> Call Trace: >>> __dump_stack lib/dump_stack.c:77 [inline] >>> dump_stack+0x188/0x20d lib/dump_stack.c:118 >>> check_preemption_disabled lib/smp_processor_id.c:47 [inline] >>> __this_cpu_preempt_check.cold+0x84/0x90 lib/smp_processor_id.c:64 >>> __mod_memcg_state+0x27/0x1a0 mm/memcontrol.c:689 >>> __split_huge_page mm/huge_memory.c:2575 [inline] >>> split_huge_page_to_list+0x124b/0x3380 mm/huge_memory.c:2862 >>> split_huge_page include/linux/huge_mm.h:167 [inline] >> It looks like a regression due to c8cba0cc2a80 ("mm/thp: narrow lru >> locking"). > > yes, I guess so. Yes, it is a stupid mistake to pull out lock for __mod_memcg_state which should be in a lock. revert this patch should be all fine, since ClearPageCompound and page_ref_inc later may related with lru_list valid issue in release_pges. Sorry for the disaster! Alex