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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 533CFC3DA7D for ; Thu, 5 Jan 2023 16:00:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234935AbjAEP7v (ORCPT ); Thu, 5 Jan 2023 10:59:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45946 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234692AbjAEP7Q (ORCPT ); Thu, 5 Jan 2023 10:59:16 -0500 Received: from out30-57.freemail.mail.aliyun.com (out30-57.freemail.mail.aliyun.com [115.124.30.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00340F66 for ; Thu, 5 Jan 2023 07:59:14 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R601e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046056;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0VYwMxZY_1672934349; Received: from 30.27.95.191(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0VYwMxZY_1672934349) by smtp.aliyun-inc.com; Thu, 05 Jan 2023 23:59:11 +0800 Message-ID: <03ada837-2504-9e69-5fec-0b7a7f186d90@linux.alibaba.com> Date: Thu, 5 Jan 2023 23:59:08 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.6.1 Subject: Re: [syzbot] [erofs?] WARNING: CPU: NUM PID: NUM at mm/page_alloc.c:LINE get_page_from_freeli To: Aleksandr Nogikh Cc: syzbot , akpm@linux-foundation.org, chao@kernel.org, linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, xiang@kernel.org References: <000000000000c0a08805f07291a0@google.com> From: Xiang Gao In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Aleksandr, On 2023/1/5 19:14, Aleksandr Nogikh wrote: > Hi, > > On Thu, Jan 5, 2023 at 11:54 AM Xiang Gao wrote: > >> I wasn't able to build the kernel with this kernel config, it shows: >> "... >> FATAL: modpost: vmlinux.o is truncated. sechdrs[i].sh_offset=1399394064 > sizeof(*hrd)=64 >> make[2]: *** [Module.symvers] Error 1 >> make[1]: *** [modpost] Error 2 >> make: *** [__sub-make] Error 2 >> " > > Could you please tell, what exact compiler/linker version did you use? Thanks for your help. GCC 9.2.1 on my developping server. > > >>> >>> Downloadable assets: >>> disk image: https://storage.googleapis.com/syzbot-assets/0c8a5f06ceb3/disk-f9ff5644.raw.xz >>> vmlinux: https://storage.googleapis.com/syzbot-assets/be222e852ae2/vmlinux-f9ff5644.xz >>> kernel image: https://storage.googleapis.com/syzbot-assets/d9f42a53b05e/bzImage-f9ff5644.xz >> >> Finally I tried the original kernel image, and it printed some other >> random bug when booting system and then reboot, like: >> >> [ 36.991123][ T1] ================================================================== >> [ 36.991800][ T1] BUG: KASAN: slab-out-of-bounds in copy_array+0x96/0x100 >> [ 36.992438][ T1] Write of size 32 at addr ffff888018c34640 by task systemd/1 > < .. > > > Interesting! > I've just tried to boot it with qemu and it was fine. > > qemu-system-x86_64 -smp 2,sockets=2,cores=1 -m 4G -drive > file=disk-f9ff5644.raw,format=raw -snapshot -nographic -enable-kvm > > So it looks like it's some difference between these VMMs that causes > that bug to fire. I think the problem is that the rootfs which I used has more complicated workload than the given one. > >> >> May I ask it can be reproducable on the latest -rc kernel? > > We can ask syzbot about v6.2-rc2: > > #syz test git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git > 88603b6dc419445847923fcb7fe5080067a30f98 I think I know the root cause: It seems that kvcalloc doesn't support GFP_NOFAIL, I will use kcalloc directly instead. Thanks, Gao Xiang > >> >> Thanks, >> Gao Xiang >> > > -- > Aleksandr