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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04B20C433F5 for ; Sun, 14 Nov 2021 15:58:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D385F60FD8 for ; Sun, 14 Nov 2021 15:58:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235295AbhKNQBb (ORCPT ); Sun, 14 Nov 2021 11:01:31 -0500 Received: from mail-io1-f71.google.com ([209.85.166.71]:37598 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230490AbhKNQBY (ORCPT ); Sun, 14 Nov 2021 11:01:24 -0500 Received: by mail-io1-f71.google.com with SMTP id w8-20020a0566022c0800b005dc06acea8dso9676897iov.4 for ; Sun, 14 Nov 2021 07:58:30 -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=SbWVnq+nDvSmXuudTBjUq/oCHiJqjz9hQVixkgRbnxQ=; b=U0MxenwYFb7Lug8FIKz9CUGN+mERToDKjdM7Y5WfrFX8qRFa5BpUdDtsRYU4FGv/oN HlVhuDeWeYHI6rQoCOm1r9h7RCO2A81cZVy1Lv3V1omLnHtPS8R8Tvf91+f40qo6W2sz N1PfDHwygyesw6/s+f9s5AvNBSkK7IeZz+mrsQw0mC0vaRaGM39MkgULqm/uwGVH5C97 +7TZwSmdHzO6ub4O9N6H5PuvO2f4OESqandGomOLepWgnaBhmKEF9+cRp97kNPrFy5Dk NLxurIDTDee/pFWHwRJkIiD9yo1X34lPOH5tO+XDSyrsUGq5Djwwiki0Eo35i8ljwDC5 JcXw== X-Gm-Message-State: AOAM530FN/eHrhkcIGhOlJHk7aqTj8W6RU83ICIx9PC/+hRxpz4LfABf pHPj/7QuMpg+b+N003r2Q5XIwGuKMsUeSPTCfwU89+1uXtVq X-Google-Smtp-Source: ABdhPJxvPwO1HHNr/AXIppzJ5JfMMiQyDq67g0m3DGxzFB3Kbko9+vhUXqQaa6Njv3BCMCMJm8gJr8pWI3b5zZ5kMsZ2nSxh/WrB MIME-Version: 1.0 X-Received: by 2002:a05:6638:1134:: with SMTP id f20mr23936092jar.6.1636905510478; Sun, 14 Nov 2021 07:58:30 -0800 (PST) Date: Sun, 14 Nov 2021 07:58:30 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000007ba8cd05d0c1c3b0@google.com> Subject: [syzbot] possible deadlock in console_lock_spinning_enable (2) From: syzbot To: gregkh@linuxfoundation.org, jirislaby@kernel.org, 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: debe436e77c7 Merge tag 'ext4_for_linus' of git://git.kerne.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=162b3b8ab00000 kernel config: https://syzkaller.appspot.com/x/.config?x=2897a869f0607967 dashboard link: https://syzkaller.appspot.com/bug?extid=3cc1054e15babd5f4cd2 compiler: Debian clang version 11.0.1-2, 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+3cc1054e15babd5f4cd2@syzkaller.appspotmail.com FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 ====================================================== WARNING: possible circular locking dependency detected 5.15.0-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/6725 is trying to acquire lock: ffffffff8cb12260 (console_owner){-.-.}-{0:0}, at: console_lock_spinning_enable+0x2d/0x60 kernel/printk/printk.c:1778 but task is already holding lock: ffff8880893d4958 (&port->lock){-.-.}-{2:2}, at: pty_write+0xc5/0x170 drivers/tty/pty.c:120 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&port->lock){-.-.}-{2:2}: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 tty_port_tty_get+0x21/0xe0 drivers/tty/tty_port.c:289 tty_port_default_wakeup+0x11/0x40 drivers/tty/tty_port.c:48 serial8250_tx_chars+0x68e/0x8a0 drivers/tty/serial/8250/8250_port.c:1845 serial8250_handle_irq+0x2fd/0x3e0 drivers/tty/serial/8250/8250_port.c:1932 serial8250_default_handle_irq+0xaf/0x190 drivers/tty/serial/8250/8250_port.c:1949 serial8250_interrupt+0xa3/0x1e0 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x20d/0x730 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:198 [inline] handle_irq_event+0x10a/0x300 kernel/irq/handle.c:215 handle_edge_irq+0x245/0xbe0 kernel/irq/chip.c:822 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:231 [inline] __common_interrupt+0xce/0x1e0 arch/x86/kernel/irq.c:250 common_interrupt+0x9f/0xc0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:404 [inline] uart_write+0x6ad/0x920 drivers/tty/serial/serial_core.c:598 do_output_char+0x638/0x940 drivers/tty/n_tty.c:444 process_output drivers/tty/n_tty.c:511 [inline] n_tty_write+0xe95/0x1320 drivers/tty/n_tty.c:2300 do_tty_write drivers/tty/tty_io.c:1038 [inline] file_tty_write+0x5c5/0x9a0 drivers/tty/tty_io.c:1110 do_iter_readv_writev+0x54f/0x740 do_iter_write+0x21e/0x7b0 fs/read_write.c:851 vfs_writev fs/read_write.c:924 [inline] do_writev+0x279/0x470 fs/read_write.c:967 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #1 (&port_lock_key){-.-.}-{2:2}: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 serial8250_console_write+0x19c/0xf30 drivers/tty/serial/8250/8250_port.c:3358 console_unlock+0xb00/0xe90 kernel/printk/printk.c:2711 vprintk_emit+0xba/0x140 kernel/printk/printk.c:2245 _printk+0xcf/0x118 kernel/printk/printk.c:2266 register_console+0x6bd/0x9a0 kernel/printk/printk.c:3051 univ8250_console_init+0x41/0x43 drivers/tty/serial/8250/8250_core.c:680 console_init+0x52/0x97 kernel/printk/printk.c:3151 start_kernel+0x32d/0x56e init/main.c:1064 secondary_startup_64_no_verify+0xb1/0xbb -> #0 (console_owner){-.-.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3063 [inline] check_prevs_add kernel/locking/lockdep.c:3186 [inline] validate_chain+0x1dfb/0x8240 kernel/locking/lockdep.c:3801 __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5027 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637 console_lock_spinning_enable+0x52/0x60 kernel/printk/printk.c:1781 console_unlock+0x834/0xe90 kernel/printk/printk.c:2708 vprintk_emit+0xba/0x140 kernel/printk/printk.c:2245 _printk+0xcf/0x118 kernel/printk/printk.c:2266 fail_dump lib/fault-inject.c:45 [inline] should_fail+0x366/0x4b0 lib/fault-inject.c:146 should_failslab+0x5/0x20 mm/slab_common.c:1320 slab_pre_alloc_hook mm/slab.h:494 [inline] slab_alloc_node mm/slub.c:3148 [inline] slab_alloc mm/slub.c:3242 [inline] __kmalloc+0x94/0x380 mm/slub.c:4419 kmalloc include/linux/slab.h:595 [inline] tty_buffer_alloc drivers/tty/tty_buffer.c:177 [inline] __tty_buffer_request_room+0x1f0/0x540 drivers/tty/tty_buffer.c:275 tty_insert_flip_string_fixed_flag+0x92/0x2c0 drivers/tty/tty_buffer.c:321 tty_insert_flip_string include/linux/tty_flip.h:42 [inline] pty_write+0xe9/0x170 drivers/tty/pty.c:122 tty_put_char+0x115/0x180 drivers/tty/tty_io.c:3174 do_output_char+0x583/0x940 drivers/tty/n_tty.c:485 __process_echoes+0x2a3/0x930 drivers/tty/n_tty.c:736 flush_echoes drivers/tty/n_tty.c:826 [inline] __receive_buf drivers/tty/n_tty.c:1579 [inline] n_tty_receive_buf_common+0x7c2d/0x81d0 drivers/tty/n_tty.c:1674 tiocsti drivers/tty/tty_io.c:2310 [inline] tty_ioctl+0xe30/0x17d0 drivers/tty/tty_io.c:2719 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: console_owner --> &port_lock_key --> &port->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&port->lock); lock(&port_lock_key); lock(&port->lock); lock(console_owner); *** DEADLOCK *** 6 locks held by syz-executor.5/6725: #0: ffff888084da5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffff8880893d60b8 (&port->buf.lock/1){+.+.}-{3:3}, at: tiocsti drivers/tty/tty_io.c:2308 [inline] #1: ffff8880893d60b8 (&port->buf.lock/1){+.+.}-{3:3}, at: tty_ioctl+0xdba/0x17d0 drivers/tty/tty_io.c:2719 #2: ffff888084da52e8 (&o_tty->termios_rwsem/1){++++}-{3:3}, at: n_tty_receive_buf_common+0x8e/0x81d0 drivers/tty/n_tty.c:1637 #3: ffffc90017a63378 (&ldata->output_lock){+.+.}-{3:3}, at: flush_echoes drivers/tty/n_tty.c:824 [inline] #3: ffffc90017a63378 (&ldata->output_lock){+.+.}-{3:3}, at: __receive_buf drivers/tty/n_tty.c:1579 [inline] #3: ffffc90017a63378 (&ldata->output_lock){+.+.}-{3:3}, at: n_tty_receive_buf_common+0x7be1/0x81d0 drivers/tty/n_tty.c:1674 #4: ffff8880893d4958 (&port->lock){-.-.}-{2:2}, at: pty_write+0xc5/0x170 drivers/tty/pty.c:120 #5: ffffffff8c9f9f00 (console_lock){+.+.}-{0:0}, at: vprintk_emit+0xa1/0x140 kernel/printk/printk.c:2244 stack backtrace: CPU: 0 PID: 6725 Comm: syz-executor.5 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 check_noncircular+0x2f9/0x3b0 kernel/locking/lockdep.c:2143 check_prev_add kernel/locking/lockdep.c:3063 [inline] check_prevs_add kernel/locking/lockdep.c:3186 [inline] validate_chain+0x1dfb/0x8240 kernel/locking/lockdep.c:3801 __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5027 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637 console_lock_spinning_enable+0x52/0x60 kernel/printk/printk.c:1781 console_unlock+0x834/0xe90 kernel/printk/printk.c:2708 vprintk_emit+0xba/0x140 kernel/printk/printk.c:2245 _printk+0xcf/0x118 kernel/printk/printk.c:2266 fail_dump lib/fault-inject.c:45 [inline] should_fail+0x366/0x4b0 lib/fault-inject.c:146 should_failslab+0x5/0x20 mm/slab_common.c:1320 slab_pre_alloc_hook mm/slab.h:494 [inline] slab_alloc_node mm/slub.c:3148 [inline] slab_alloc mm/slub.c:3242 [inline] __kmalloc+0x94/0x380 mm/slub.c:4419 kmalloc include/linux/slab.h:595 [inline] tty_buffer_alloc drivers/tty/tty_buffer.c:177 [inline] __tty_buffer_request_room+0x1f0/0x540 drivers/tty/tty_buffer.c:275 tty_insert_flip_string_fixed_flag+0x92/0x2c0 drivers/tty/tty_buffer.c:321 tty_insert_flip_string include/linux/tty_flip.h:42 [inline] pty_write+0xe9/0x170 drivers/tty/pty.c:122 tty_put_char+0x115/0x180 drivers/tty/tty_io.c:3174 do_output_char+0x583/0x940 drivers/tty/n_tty.c:485 __process_echoes+0x2a3/0x930 drivers/tty/n_tty.c:736 flush_echoes drivers/tty/n_tty.c:826 [inline] __receive_buf drivers/tty/n_tty.c:1579 [inline] n_tty_receive_buf_common+0x7c2d/0x81d0 drivers/tty/n_tty.c:1674 tiocsti drivers/tty/tty_io.c:2310 [inline] tty_ioctl+0xe30/0x17d0 drivers/tty/tty_io.c:2719 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa76cdb3ae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa76a2e7188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa76cec70e0 RCX: 00007fa76cdb3ae9 RDX: 0000000020000100 RSI: 0000000000005412 RDI: 0000000000000004 RBP: 00007fa76a2e71d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff471d4ccf R14: 00007fa76a2e7300 R15: 0000000000022000 CPU: 0 PID: 6725 Comm: syz-executor.5 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 fail_dump lib/fault-inject.c:52 [inline] should_fail+0x384/0x4b0 lib/fault-inject.c:146 should_failslab+0x5/0x20 mm/slab_common.c:1320 slab_pre_alloc_hook mm/slab.h:494 [inline] slab_alloc_node mm/slub.c:3148 [inline] slab_alloc mm/slub.c:3242 [inline] __kmalloc+0x94/0x380 mm/slub.c:4419 kmalloc include/linux/slab.h:595 [inline] tty_buffer_alloc drivers/tty/tty_buffer.c:177 [inline] __tty_buffer_request_room+0x1f0/0x540 drivers/tty/tty_buffer.c:275 tty_insert_flip_string_fixed_flag+0x92/0x2c0 drivers/tty/tty_buffer.c:321 tty_insert_flip_string include/linux/tty_flip.h:42 [inline] pty_write+0xe9/0x170 drivers/tty/pty.c:122 tty_put_char+0x115/0x180 drivers/tty/tty_io.c:3174 do_output_char+0x583/0x940 drivers/tty/n_tty.c:485 __process_echoes+0x2a3/0x930 drivers/tty/n_tty.c:736 flush_echoes drivers/tty/n_tty.c:826 [inline] __receive_buf drivers/tty/n_tty.c:1579 [inline] n_tty_receive_buf_common+0x7c2d/0x81d0 drivers/tty/n_tty.c:1674 tiocsti drivers/tty/tty_io.c:2310 [inline] tty_ioctl+0xe30/0x17d0 drivers/tty/tty_io.c:2719 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa76cdb3ae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa76a2e7188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa76cec70e0 RCX: 00007fa76cdb3ae9 RDX: 0000000020000100 RSI: 0000000000005412 RDI: 0000000000000004 RBP: 00007fa76a2e71d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff471d4ccf R14: 00007fa76a2e7300 R15: 0000000000022000 --- This report is generated by a bot. 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