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=-5.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 C60ADCA9EA0 for ; Sun, 20 Oct 2019 23:33:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9CB9F21928 for ; Sun, 20 Oct 2019 23:33:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726687AbfJTXdO (ORCPT ); Sun, 20 Oct 2019 19:33:14 -0400 Received: from mail-io1-f69.google.com ([209.85.166.69]:38961 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726571AbfJTXdO (ORCPT ); Sun, 20 Oct 2019 19:33:14 -0400 Received: by mail-io1-f69.google.com with SMTP id f9so15819378ioh.6 for ; Sun, 20 Oct 2019 16:33:12 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:in-reply-to:message-id:subject :from:to; bh=LcnS/BPD4aOM4PxSo8Hv9J5ZaoK/k6pTFOh7ysR2NzA=; b=J3pWDkO6Nroh6IvHQEU7TbqcU9BXouP8FrsUJQNRz9W+bONMCLEnstv/ZiffnQdfIA +kWHqXGc9AFr5YaX3Z9mKRRavwHDjOcCJ5yq1obzB1/pXmFOQ3JNzlY9g5CPrqTbKrNF YeC2D1sneDPwOUOKI/jVuOOsteOGSGH8P4AXQXlwjX8uQkpsxqmGXUtg/aHNHxL8lwgp TVKrrIP8tcjuyRP5Hn9kH+QZy8QlFhBsfM1Jlp+ISkTQKBPv+7wGdqG9YCZkGpRLtDxA n7ff7px02WaEjZUBJ6vgHMy5QKmihPr76WTCjVl4psJw0KizWl4lGC4XMXGj7ENSkP1R rPdA== X-Gm-Message-State: APjAAAV0rlk98osHuhUJP6bPdg+z/+TMkiZNSPWgvaO3phCnpQVwmXBE zZLaPIHHRo1rXtgPxy4143a34Az6w4G/w7vh0BKQCpjDJfOd X-Google-Smtp-Source: APXvYqy69ZWKiOaduR7XD3ZyDqZK5jSo6DR/VXXqXiPU9YPMlYvsCItsg8muyIm41ImBvZ+3rVIakLvZj3kw5IN8BZGfV5lJQ8v3 MIME-Version: 1.0 X-Received: by 2002:a6b:7104:: with SMTP id q4mr2713358iog.129.1571614391673; Sun, 20 Oct 2019 16:33:11 -0700 (PDT) Date: Sun, 20 Oct 2019 16:33:11 -0700 In-Reply-To: <0000000000007523a60576e80a47@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000008a279405955ffd35@google.com> Subject: Re: BUG: MAX_LOCKDEP_CHAINS too low! From: syzbot To: dvyukov@google.com, linux-kernel@vger.kernel.org, mingo@kernel.org, peterz@infradead.org, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, will.deacon@arm.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzbot has found a reproducer for the following crash on: HEAD commit: 4fe34d61 Merge branch 'x86-urgent-for-linus' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1176cd40e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=e0ac4d9b35046343 dashboard link: https://syzkaller.appspot.com/bug?extid=aaa6fa4949cc5d9b7b25 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14150b40e00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12e122ff600000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+aaa6fa4949cc5d9b7b25@syzkaller.appspotmail.com BUG: MAX_LOCKDEP_CHAINS too low! turning off the locking correctness validator. CPU: 0 PID: 11772 Comm: kworker/u5:486 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci1600 hci_power_on Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 add_chain_cache kernel/locking/lockdep.c:2816 [inline] lookup_chain_cache_add kernel/locking/lockdep.c:2915 [inline] validate_chain kernel/locking/lockdep.c:2936 [inline] __lock_acquire.cold+0x325/0x385 kernel/locking/lockdep.c:3955 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 process_one_work+0x91c/0x1740 kernel/workqueue.c:2245 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352