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=-9.0 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 41C04C433E1 for ; Sat, 15 Aug 2020 21:56:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 284A6206B6 for ; Sat, 15 Aug 2020 21:56:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726587AbgHOV4c (ORCPT ); Sat, 15 Aug 2020 17:56:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729033AbgHOVwN (ORCPT ); Sat, 15 Aug 2020 17:52:13 -0400 Received: from mail-il1-x145.google.com (mail-il1-x145.google.com [IPv6:2607:f8b0:4864:20::145]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E3E0C0F26E9 for ; Sat, 15 Aug 2020 11:09:18 -0700 (PDT) Received: by mail-il1-x145.google.com with SMTP id k8so5081407ili.21 for ; Sat, 15 Aug 2020 11:09:18 -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=unqY6YUA6dN15yzdjEHwLUsw603J7sn/Dlnt+ztMhZk=; b=BzzAxLqK4aleMkYITIKN4JIDc+KRcqSqq0HVjUsZIZKtD1Az5GKa935zZNpg+vJibx Mi9EBIIqEYWdRTUnvlNTZVGkknwDfOLdWsBpIdzBwlG+aoroV+qEjWromfndphqR40wg auPFh7MYnVzUtZnSAMm7nOQKba0720lbNfjz5jx5knioyqWKObGgd+XtkZozqCoAXkfE cvXymtq9u9Rv0hgbWtYY/8NPBDXr6us5mbCvG1/0UllLqStalBlQzeuV3oN0N+69RB9R SPR7/7BOiWzOdAk0ujMKI1LmDdjmTHZUky22KklJSieClOgPol8Dq97rOW1Y0hZBU5Pa kFfw== X-Gm-Message-State: AOAM5315kwYGnmMN/GlOwcBosaPfWO2T6XttK7hJPwUKpnzdu0LwvCKs W24dzzmsuvb0ZzRdsaHwibS+SveV1tI8X0r9FKnKhHwzIki/ X-Google-Smtp-Source: ABdhPJyo0N5X3Rr63x6KSCF9oemLGrgNQNTncv3rJKuvDN2i4ehbpeDid+q3ScpJ7466Pv+uSxM9s3V5J1KUjpfsGtCJJtdgE45x MIME-Version: 1.0 X-Received: by 2002:a92:bf0c:: with SMTP id z12mr7149150ilh.151.1597514957600; Sat, 15 Aug 2020 11:09:17 -0700 (PDT) Date: Sat, 15 Aug 2020 11:09:17 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000923cee05acee6f61@google.com> Subject: possible deadlock in io_poll_double_wake From: syzbot To: axboe@kernel.dk, io-uring@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8" Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: c9c9735c Merge tag 'scsi-misc' of git://git.kernel.org/pub.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=127399f6900000 kernel config: https://syzkaller.appspot.com/x/.config?x=adea84f38e7bc8d dashboard link: https://syzkaller.appspot.com/bug?extid=0d56cfeec64f045baffc compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) 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+0d56cfeec64f045baffc@syzkaller.appspotmail.com ============================================ WARNING: possible recursive locking detected 5.8.0-syzkaller #0 Not tainted -------------------------------------------- syz-executor.1/9155 is trying to acquire lock: ffff8880a1fcc530 (&tty->write_wait){-.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] ffff8880a1fcc530 (&tty->write_wait){-.-.}-{2:2}, at: io_poll_double_wake+0x108/0x360 fs/io_uring.c:4599 but task is already holding lock: ffff8880a1fcc530 (&tty->write_wait){-.-.}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:122 [inline] ffff8880a1fcc530 (&tty->write_wait){-.-.}-{2:2}, at: __wake_up+0xb8/0x150 kernel/sched/wait.c:142 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&tty->write_wait); lock(&tty->write_wait); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by syz-executor.1/9155: #0: ffff8880a1fcc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:267 #1: ffff8880a1fcc2e8 (&tty->termios_rwsem){++++}-{3:3}, at: tty_set_termios+0xc5/0x1510 drivers/tty/tty_ioctl.c:328 #2: ffff8880a1fcc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x18/0x80 drivers/tty/tty_ldisc.c:288 #3: ffff8880a1fcc530 (&tty->write_wait){-.-.}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:122 [inline] #3: ffff8880a1fcc530 (&tty->write_wait){-.-.}-{2:2}, at: __wake_up+0xb8/0x150 kernel/sched/wait.c:142 stack backtrace: CPU: 0 PID: 9155 Comm: syz-executor.1 Not tainted 5.8.0-syzkaller #0 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+0x1f0/0x31e lib/dump_stack.c:118 print_deadlock_bug kernel/locking/lockdep.c:2391 [inline] check_deadlock kernel/locking/lockdep.c:2432 [inline] validate_chain+0x69a4/0x88a0 kernel/locking/lockdep.c:3202 __lock_acquire+0x1161/0x2ab0 kernel/locking/lockdep.c:4426 lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] io_poll_double_wake+0x108/0x360 fs/io_uring.c:4599 __wake_up_common+0x30a/0x4e0 kernel/sched/wait.c:93 __wake_up_common_lock kernel/sched/wait.c:123 [inline] __wake_up+0xd4/0x150 kernel/sched/wait.c:142 n_tty_set_termios+0xa60/0x1080 drivers/tty/n_tty.c:1874 tty_set_termios+0xcac/0x1510 drivers/tty/tty_ioctl.c:341 set_termios+0x4a1/0x580 drivers/tty/tty_ioctl.c:414 tty_mode_ioctl+0x7b2/0xa80 drivers/tty/tty_ioctl.c:770 tty_ioctl+0xf81/0x15c0 drivers/tty/tty_io.c:2665 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d239 Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f063db5fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000017cc0 RCX: 000000000045d239 RDX: 0000000020000000 RSI: 0000000000005404 RDI: 0000000000000003 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffc7ff6341f R14: 00007f063db609c0 R15: 000000000118cf4c --- 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.