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 4C7BDC433F5 for ; Fri, 14 Jan 2022 09:09:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239694AbiANJJS (ORCPT ); Fri, 14 Jan 2022 04:09:18 -0500 Received: from mail-il1-f200.google.com ([209.85.166.200]:52133 "EHLO mail-il1-f200.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239644AbiANJJR (ORCPT ); Fri, 14 Jan 2022 04:09:17 -0500 Received: by mail-il1-f200.google.com with SMTP id d8-20020a056e02214800b002b766d01bf5so5746442ilv.18 for ; Fri, 14 Jan 2022 01:09:17 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=grHxCRd7/fDYY0i9cGDsjoRzJRJ5aOkbW3ALA1psZtI=; b=SnHJrHKhSp5Rk87gupTIB0ZuFMapdHte4mM3FRH8SGKNd9hZSZPPbZeKyQHbhWUfNw WQMjlKesp3IOwTM/R2W9MxExACf2rv+5QIYBfFDwuNvIKEdxWJ0dhbV1efd6s9cZy6e+ kuqTfGHxT2JP6hi3+UHB9zAhU+o04N41hlH2zW/HDathsL57Z9QdqRW2f5WXmFaogCzN /V3RD65U0PIwPcwA/1WwAygPUr6d+29j8IuJ97zDD5QxT0GMIfM/L2FwkjJstzC0QGz+ 0Gl4g60uOkwReTiVwr8O/RcAQ1RpH81jGALKywsDQaianN8jnkwqwuPTmohcKXZqOgjv OuUQ== X-Gm-Message-State: AOAM533tSK5RrNwoTnzABbHOwggk1+yDgi64ugxcNkOh5991yHhf9r1h 28+ud7cOtTm+8Qh6MQ8VCpHYLI32j654HNKktAeiOQSlWsZf X-Google-Smtp-Source: ABdhPJzrtzL3KtaKjcbS2baa8Qd4awayCo48Py4S2a3t1Oj2zYk/kDJec2Lpeaz7tQ2eeoftXXRshiw/OHvPgFXiLmNUMwVJAmyC MIME-Version: 1.0 X-Received: by 2002:a05:6602:3c6:: with SMTP id g6mr3954432iov.213.1642151356982; Fri, 14 Jan 2022 01:09:16 -0800 (PST) Date: Fri, 14 Jan 2022 01:09:16 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000004cede805d58728c3@google.com> Subject: [syzbot] possible deadlock in f2fs_write_checkpoint From: syzbot To: chao@kernel.org, jaegeuk@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: 57c149e506d5 Add linux-next specific files for 20220110 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=15cb8b77b00000 kernel config: https://syzkaller.appspot.com/x/.config?x=2f1cca5543ac6349 dashboard link: https://syzkaller.appspot.com/bug?extid=0b9cadf5fc45a98a5083 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0b9cadf5fc45a98a5083@syzkaller.appspotmail.com ============================================ WARNING: possible recursive locking detected 5.16.0-rc8-next-20220110-syzkaller #0 Not tainted -------------------------------------------- f2fs_ckpt-7:2/4139 is trying to acquire lock: ffff88807c598390 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2149 [inline] ffff88807c598390 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: f2fs_write_checkpoint+0x535/0x5d00 fs/f2fs/checkpoint.c:1615 but task is already holding lock: ffff88807c599338 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2149 [inline] ffff88807c599338 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: __write_checkpoint_sync fs/f2fs/checkpoint.c:1744 [inline] ffff88807c599338 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: __checkpoint_and_complete_reqs+0xdd/0x360 fs/f2fs/checkpoint.c:1764 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sem->internal_rwsem#2); lock(&sem->internal_rwsem#2); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by f2fs_ckpt-7:2/4139: #0: ffff88807c599338 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2149 [inline] #0: ffff88807c599338 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: __write_checkpoint_sync fs/f2fs/checkpoint.c:1744 [inline] #0: ffff88807c599338 (&sem->internal_rwsem#2){+.+.}-{3:3}, at: __checkpoint_and_complete_reqs+0xdd/0x360 fs/f2fs/checkpoint.c:1764 stack backtrace: CPU: 0 PID: 4139 Comm: f2fs_ckpt-7:2 Not tainted 5.16.0-rc8-next-20220110-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 down_write+0x90/0x150 kernel/locking/rwsem.c:1514 f2fs_down_write fs/f2fs/f2fs.h:2149 [inline] f2fs_write_checkpoint+0x535/0x5d00 fs/f2fs/checkpoint.c:1615 __write_checkpoint_sync fs/f2fs/checkpoint.c:1745 [inline] __checkpoint_and_complete_reqs+0xea/0x360 fs/f2fs/checkpoint.c:1764 issue_checkpoint_thread+0xdf/0x250 fs/f2fs/checkpoint.c:1795 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 --- This report 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 issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.