====================================================== WARNING: possible circular locking dependency detected 5.17.0-rc5-next-20220222-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/3712 is trying to acquire lock: ffff8880b9d395d8 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x366/0x1140 kernel/workqueue.c:1474 but task is already holding lock: ffffffff9061a530 (&port_lock_key){-.-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:379 [inline] ffffffff9061a530 (&port_lock_key){-.-.}-{2:2}, at: uart_carrier_raised+0xdc/0x290 drivers/tty/serial/serial_core.c:1711 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&port_lock_key){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 serial8250_console_write+0x91a/0xb70 drivers/tty/serial/8250/8250_port.c:3359 call_console_drivers kernel/printk/printk.c:1953 [inline] console_unlock+0x9bc/0xdd0 kernel/printk/printk.c:2775 vprintk_emit+0x1b4/0x5f0 kernel/printk/printk.c:2273 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2294 register_console kernel/printk/printk.c:3132 [inline] register_console+0x410/0x7c0 kernel/printk/printk.c:3013 univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:679 console_init+0x3c1/0x58d kernel/printk/printk.c:3232 start_kernel+0x30b/0x4a0 init/main.c:1068 secondary_startup_64_no_verify+0xc3/0xcb -> #1 (console_owner){....}-{0:0}: console_lock_spinning_enable kernel/printk/printk.c:1795 [inline] console_unlock+0x3b1/0xdd0 kernel/printk/printk.c:2772 vprintk_emit+0x1b4/0x5f0 kernel/printk/printk.c:2273 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2294 warn_flush_attempt kernel/workqueue.c:2613 [inline] check_flush_dependency.cold+0x18/0x4e kernel/workqueue.c:2635 start_flush_work kernel/workqueue.c:3049 [inline] __flush_work+0x25a/0xb10 kernel/workqueue.c:3091 flush_all_cpus_locked+0x148/0x1b0 mm/slub.c:2728 flush_all mm/slub.c:2737 [inline] __kmem_cache_shrink+0x11/0x20 mm/slub.c:4640 acpi_os_purge_cache+0x11/0x20 drivers/acpi/osl.c:1666 acpi_purge_cached_objects+0x37/0xd0 drivers/acpi/acpica/utxface.c:237 acpi_initialize_objects+0x2b/0x95 drivers/acpi/acpica/utxfinit.c:250 acpi_bus_init drivers/acpi/bus.c:1237 [inline] acpi_init+0x1d2/0x976 drivers/acpi/bus.c:1325 do_one_initcall+0x103/0x650 init/main.c:1302 do_initcall_level init/main.c:1375 [inline] do_initcalls init/main.c:1391 [inline] do_basic_setup init/main.c:1410 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1615 kernel_init+0x1a/0x1d0 init/main.c:1504 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 -> #0 (&pool->lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3096 [inline] check_prevs_add kernel/locking/lockdep.c:3219 [inline] validate_chain kernel/locking/lockdep.c:3834 [inline] __lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5060 lock_acquire kernel/locking/lockdep.c:5672 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5637 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 __queue_work+0x366/0x1140 kernel/workqueue.c:1474 queue_work_on+0xee/0x110 kernel/workqueue.c:1545 uart_handle_dcd_change+0x1e1/0x2b0 drivers/tty/serial/serial_core.c:3090 serial8250_modem_status+0x277/0x2c0 drivers/tty/serial/8250/8250_port.c:1880 serial8250_do_get_mctrl+0xac/0x320 drivers/tty/serial/8250/8250_port.c:2012 serial8250_get_mctrl+0x56/0x70 drivers/tty/serial/8250/8250_port.c:2027 uart_carrier_raised+0x17d/0x290 drivers/tty/serial/serial_core.c:1713 tty_port_carrier_raised drivers/tty/tty_port.c:430 [inline] tty_port_block_til_ready+0x443/0x980 drivers/tty/tty_port.c:549 tty_port_open+0x196/0x1f0 drivers/tty/tty_port.c:773 uart_open+0x3e/0x60 drivers/tty/serial/serial_core.c:1758 tty_open+0x407/0x1000 drivers/tty/tty_io.c:2150 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b9/0x1250 fs/open.c:957 do_open fs/namei.c:3476 [inline] path_openat+0x1c9e/0x2940 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1347 do_sys_open fs/open.c:1363 [inline] __do_sys_openat fs/open.c:1379 [inline] __se_sys_openat fs/open.c:1374 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1374 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: &pool->lock --> console_owner --> &port_lock_key Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&port_lock_key); lock(console_owner); lock(&port_lock_key); lock(&pool->lock); *** DEADLOCK *** 3 locks held by syz-executor.0/3712: #0: ffff88806d1361c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_lock_interruptible+0xca/0x170 drivers/tty/tty_mutex.c:31 #1: ffffffff9061a530 (&port_lock_key){-.-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:379 [inline] #1: ffffffff9061a530 (&port_lock_key){-.-.}-{2:2}, at: uart_carrier_raised+0xdc/0x290 drivers/tty/serial/serial_core.c:1711 #2: ffffffff8bb866a0 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xd0/0x1140 kernel/workqueue.c:1437 stack backtrace: CPU: 1 PID: 3712 Comm: syz-executor.0 Not tainted 5.17.0-rc5-next-20220222-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 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2176 check_prev_add kernel/locking/lockdep.c:3096 [inline] check_prevs_add kernel/locking/lockdep.c:3219 [inline] validate_chain kernel/locking/lockdep.c:3834 [inline] __lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5060 lock_acquire kernel/locking/lockdep.c:5672 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5637 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 __queue_work+0x366/0x1140 kernel/workqueue.c:1474 queue_work_on+0xee/0x110 kernel/workqueue.c:1545 uart_handle_dcd_change+0x1e1/0x2b0 drivers/tty/serial/serial_core.c:3090 serial8250_modem_status+0x277/0x2c0 drivers/tty/serial/8250/8250_port.c:1880 serial8250_do_get_mctrl+0xac/0x320 drivers/tty/serial/8250/8250_port.c:2012 serial8250_get_mctrl+0x56/0x70 drivers/tty/serial/8250/8250_port.c:2027 uart_carrier_raised+0x17d/0x290 drivers/tty/serial/serial_core.c:1713 tty_port_carrier_raised drivers/tty/tty_port.c:430 [inline] tty_port_block_til_ready+0x443/0x980 drivers/tty/tty_port.c:549 tty_port_open+0x196/0x1f0 drivers/tty/tty_port.c:773 uart_open+0x3e/0x60 drivers/tty/serial/serial_core.c:1758 tty_open+0x407/0x1000 drivers/tty/tty_io.c:2150 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b9/0x1250 fs/open.c:957 do_open fs/namei.c:3476 [inline] path_openat+0x1c9e/0x2940 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1347 do_sys_open fs/open.c:1363 [inline] __do_sys_openat fs/open.c:1379 [inline] __se_sys_openat fs/open.c:1374 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1374 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3b44a89049 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3b45c4e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f3b44b9bf60 RCX: 00007f3b44a89049 RDX: 0000000000000041 RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 00007f3b44ae308d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffefc48997f R14: 00007f3b45c4e300 R15: 0000000000022000