From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f200.google.com (mail-il1-f200.google.com [209.85.166.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 11FD51428D for ; Wed, 17 Jan 2024 10:03:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.200 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705485807; cv=none; b=OSXSo45ECAAAHL99vmeC6Gt1+ISHlWPbIpdAKcpkhGx2T6vIQtSwkQH7pept1poMgiRozH6TGIPUqiw9mzJgmhiPUaj+X2i4CsRUksDc5AgnVO7OWh0BCazvlju6POrJ1F7V5P9GODztb2LsGrkCOvMdpXwcFBtjNVfj3NrcB/8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705485807; c=relaxed/simple; bh=6Ba35sjl5j77N2GQR5J5Qza9P7y57/tDDptoGf9OcXI=; h=Received:X-Google-DKIM-Signature:X-Gm-Message-State: X-Google-Smtp-Source:MIME-Version:X-Received:Date: X-Google-Appengine-App-Id:X-Google-Appengine-App-Id-Alias: Message-ID:Subject:From:To:Content-Type; b=dOefEPLCj3xja5TByNGo0H4TLG13kr30ceJ7dQwYTh8SrvPJVhgWf4JTtE+BU2Sy8M8tayqscBJWUnDsMeL9uzBxunngzNhYknR/Ro4+UbhpfTxxT7Gg57V8k3d4fyDEiU/IG7OOXpebdQne59eiKFS8fYPwihYMIXhfRn1whzo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f200.google.com with SMTP id e9e14a558f8ab-35fc6976630so88200735ab.0 for ; Wed, 17 Jan 2024 02:03:25 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705485805; x=1706090605; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=XnlLyvOefL1ydIX1ocF93Tqp6b+HX/ZrHqzQLe9vBGQ=; b=FqtNNblxLtTa4Mxu8WTLcZMKyI8qgFMkAAnFsTqSUxkf43Em6tXAYAAQzta4KFkl7r Z4tpYcN7h5NRz1dRnD+EJiGxs8d3vbaN8ZmUdawPrTko+p7MLi7MV+Dh0NrcL3rp1NAn 4uNvCGzKBOwRi25uJQRmxduVTOJjlG5M2hSe1QWOiCpdOCRlz0vmff9JoNR4KpUJRQAs LGn0ji8egaKF7bKXtXaltjUVaEi782Vboy9ychCrbwRDIYRtgUVNgTFYQxIWS2npRaqg eAtwr3oRKL+Mq30Bb7XXPwFMqU9+4YxjLYdojDNzIFK4VGtyJCdXpj4NBugWtv6CXkHm Gwew== X-Gm-Message-State: AOJu0YzytHICNnb30HPPncVmn20gldY3kairK9JaTJ/WOFP2MWNf3nfa dSnuIhMbZK550WaNXCdf5E8x6Dj1BOnhJ+HW44G6Sr88Le2w X-Google-Smtp-Source: AGHT+IGvV1agZFiqt/a//m5HZbLHbz1/WZWfpE0D+BlA/d5KlOxjXPWsR2fYtwiSR0/K9fKYRy4Y+8tEhqSYGeXfTim+0tv4CjwG Precedence: bulk X-Mailing-List: linux-bluetooth@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a92:c565:0:b0:360:134:54b1 with SMTP id b5-20020a92c565000000b00360013454b1mr1232890ilj.0.1705485805272; Wed, 17 Jan 2024 02:03:25 -0800 (PST) Date: Wed, 17 Jan 2024 02:03:25 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000097c554060f215b50@google.com> Subject: [syzbot] [bluetooth?] possible deadlock in __flush_workqueue From: syzbot To: johan.hedberg@gmail.com, linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org, luiz.dentz@gmail.com, marcel@holtmann.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 943b9f0ab2cf Add linux-next specific files for 20240117 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=121de2fbe80000 kernel config: https://syzkaller.appspot.com/x/.config?x=12af1d067b6a6d19 dashboard link: https://syzkaller.appspot.com/bug?extid=da0a9c9721e36db712e8 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/9c032ce79e0f/disk-943b9f0a.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/93163e287878/vmlinux-943b9f0a.xz kernel image: https://storage.googleapis.com/syzbot-assets/512cc2e14a4b/bzImage-943b9f0a.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+da0a9c9721e36db712e8@syzkaller.appspotmail.com Bluetooth: hci2: Opcode 0x0c03 failed: -110 ============================================ WARNING: possible recursive locking detected 6.7.0-next-20240117-syzkaller #0 Not tainted -------------------------------------------- kworker/u5:1/21244 is trying to acquire lock: ffff88802e0a2538 ((wq_completion)hci2){+.+.}-{0:0}, at: __flush_workqueue+0x141/0x1340 kernel/workqueue.c:3147 but task is already holding lock: ffff88802e0a2538 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work+0x7ba/0x16e0 kernel/workqueue.c:2608 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock((wq_completion)hci2); lock((wq_completion)hci2); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by kworker/u5:1/21244: #0: ffff88802e0a2538 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work+0x7ba/0x16e0 kernel/workqueue.c:2608 #1: ffffc9000dc27d80 ((work_completion)(&hdev->error_reset)){+.+.}-{0:0}, at: process_one_work+0x824/0x16e0 kernel/workqueue.c:2609 stack backtrace: CPU: 1 PID: 21244 Comm: kworker/u5:1 Not tainted 6.7.0-next-20240117-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: hci2 hci_error_reset Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain kernel/locking/lockdep.c:3856 [inline] __lock_acquire+0x20e6/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __flush_workqueue+0x14b/0x1340 kernel/workqueue.c:3147 drain_workqueue+0x18f/0x3d0 kernel/workqueue.c:3312 destroy_workqueue+0xc3/0xb10 kernel/workqueue.c:4801 hci_release_dev+0x14e/0x620 net/bluetooth/hci_core.c:2808 bt_host_release+0x6a/0xb0 net/bluetooth/hci_sysfs.c:94 device_release+0xa1/0x240 drivers/base/core.c:2485 kobject_cleanup lib/kobject.c:682 [inline] kobject_release lib/kobject.c:716 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1d0/0x440 lib/kobject.c:733 put_device+0x1f/0x30 drivers/base/core.c:3733 process_one_work+0x8d5/0x16e0 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2707 [inline] worker_thread+0x8b6/0x1290 kernel/workqueue.c:2788 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242 --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup