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=-0.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 39636C3A59B for ; Fri, 30 Aug 2019 19:28:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1951621897 for ; Fri, 30 Aug 2019 19:28:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728241AbfH3T2P (ORCPT ); Fri, 30 Aug 2019 15:28:15 -0400 Received: from mail-io1-f69.google.com ([209.85.166.69]:43649 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728154AbfH3T2J (ORCPT ); Fri, 30 Aug 2019 15:28:09 -0400 Received: by mail-io1-f69.google.com with SMTP id q26so9679967ioi.10 for ; Fri, 30 Aug 2019 12:28:09 -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:message-id:subject:from:to; bh=aslq8WbI7sl258ogTqxoqYwMQreox4L8FhFx1BHXH+8=; b=oPAZvjxtByFR8l/4uiyYBPAR24mQT0glnLjAX+KiJ8XJ/nmt9BjgVnsT1nFT3iFl1I Ch12s1o/BiP9P+m/PnG80sNdUJaN38G1++dK8z1d/8UaBQ0soen3y56pW7cZgBYRVaU5 z9FnksRrghmfyonxRV/hXZej9zoNyOcccLo6keC8fsws+K/t6Ez2qBotBI0eLo8Xm1Qy UtHPtqzgJ969DyBl4kvJbqv86UOInotepaJCZImK60414yTxL7IqlBk8a26DGht4CfaI gjR3tuH9UfKRAnjIHoNqwv/0FUn4hjMODBoiz7O4VqNOuyxpcZGy5Ul77MUGwcTQbkGF 5gMw== X-Gm-Message-State: APjAAAUsXRY8ML5gMN8ECAPIvYB5/N/btjajvFh2nfzia9Df5/W4hmRL yFalXgDEgMhGqqhr7AlQHtllv1D3QKnweRPmqzZi0FIk82Y2 X-Google-Smtp-Source: APXvYqzN3n3JD6vBoBDCDagvbEYokl+smV3OkA9CBX+rF8MMuQmEQfrrxlNrCZwHz7QwotylScfq6aDW/cIf3W1Ym7nYHXRqKip5 MIME-Version: 1.0 X-Received: by 2002:a5d:8913:: with SMTP id b19mr14031111ion.83.1567193288766; Fri, 30 Aug 2019 12:28:08 -0700 (PDT) Date: Fri, 30 Aug 2019 12:28:08 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000457d1405915a9f19@google.com> Subject: WARNING: suspicious RCU usage in ext4_release_system_zone From: syzbot To: adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tytso@mit.edu Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: ed858b88 Add linux-next specific files for 20190826 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=121b506c600000 kernel config: https://syzkaller.appspot.com/x/.config?x=ee8373cd9733e305 dashboard link: https://syzkaller.appspot.com/bug?extid=5bda120b4032f831c57f compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+5bda120b4032f831c57f@syzkaller.appspotmail.com ============================= WARNING: suspicious RCU usage 5.3.0-rc6-next-20190826 #73 Not tainted ----------------------------- fs/ext4/block_validity.c:333 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syz-executor.4/8779: #0: ffff888091c4a518 (&type->s_umount_key#32){++++}, at: deactivate_super fs/super.c:363 [inline] #0: ffff888091c4a518 (&type->s_umount_key#32){++++}, at: deactivate_super+0x1aa/0x1d0 fs/super.c:360 stack backtrace: CPU: 0 PID: 8779 Comm: syz-executor.4 Not tainted 5.3.0-rc6-next-20190826 #73 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+0x172/0x1f0 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5438 ext4_release_system_zone+0x166/0x1a0 fs/ext4/block_validity.c:333 ext4_put_super+0x954/0xd70 fs/ext4/super.c:992 generic_shutdown_super+0x14c/0x370 fs/super.c:460 kill_block_super+0xa0/0x100 fs/super.c:1434 deactivate_locked_super+0x95/0x100 fs/super.c:333 deactivate_super fs/super.c:364 [inline] deactivate_super+0x1b2/0x1d0 fs/super.c:360 cleanup_mnt+0x351/0x4c0 fs/namespace.c:1102 __cleanup_mnt+0x16/0x20 fs/namespace.c:1109 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c2a7 Code: 64 89 04 25 d0 02 00 00 58 5f ff d0 48 89 c7 e8 2f be ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 9d 8d fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fffdccad768 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000045c2a7 RDX: 0000000000403520 RSI: 0000000000000002 RDI: 00007fffdccad810 RBP: 000000000000011b R08: 0000000000000000 R09: 000000000000000b R10: 0000000000000005 R11: 0000000000000202 R12: 00007fffdccae8a0 R13: 00005555565a4940 R14: 0000000000000000 R15: 00007fffdccae8a0 ------------[ cut here ]------------ ODEBUG: free active (active state 0) object type: percpu_counter hint: 0x0 WARNING: CPU: 1 PID: 8779 at lib/debugobjects.c:481 debug_print_object+0x168/0x250 lib/debugobjects.c:481 --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.