====================================================== WARNING: possible circular locking dependency detected 5.17.0-rc5-next-20220222-syzkaller #0 Not tainted ------------------------------------------------------ ksoftirqd/0/15 is trying to acquire lock: ffff8880b9c395d8 (&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: serial8250_handle_irq.part.0+0x21/0x3d0 drivers/tty/serial/8250/8250_port.c:1916 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_handle_irq.part.0+0xa1/0x3d0 drivers/tty/serial/8250/8250_port.c:1937 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1913 [inline] serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1957 serial8250_interrupt+0xfd/0x200 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x22b/0x880 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xa7/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:817 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:231 [inline] __common_interrupt+0x9d/0x210 arch/x86/kernel/irq.c:250 common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629 _raw_spin_lock_irqsave+0x2/0x50 kernel/locking/spinlock.c:161 debug_object_deactivate lib/debugobjects.c:735 [inline] debug_object_deactivate+0x101/0x300 lib/debugobjects.c:723 debug_rcu_head_unqueue kernel/rcu/rcu.h:197 [inline] rcu_do_batch kernel/rcu/tree.c:2554 [inline] rcu_core+0x769/0x1880 kernel/rcu/tree.c:2812 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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 ksoftirqd/0/15: #0: ffff88807a78f9b0 (&i->lock){-.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] #0: ffff88807a78f9b0 (&i->lock){-.-.}-{2:2}, at: serial8250_interrupt+0x3a/0x200 drivers/tty/serial/8250/8250_core.c:116 #1: ffffffff9061a530 (&port_lock_key){-.-.}-{2:2}, at: serial8250_handle_irq.part.0+0x21/0x3d0 drivers/tty/serial/8250/8250_port.c:1916 #2: ffffffff8bb866a0 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xd0/0x1140 kernel/workqueue.c:1437 stack backtrace: CPU: 0 PID: 15 Comm: ksoftirqd/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_handle_irq.part.0+0xa1/0x3d0 drivers/tty/serial/8250/8250_port.c:1937 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1913 [inline] serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1957 serial8250_interrupt+0xfd/0x200 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x22b/0x880 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xa7/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:817 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:231 [inline] __common_interrupt+0x9d/0x210 arch/x86/kernel/irq.c:250 common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629 RIP: 0010:_raw_spin_lock_irqsave+0x2/0x50 kernel/locking/spinlock.c:161 Code: 18 31 d2 31 f6 e8 6e d3 0b f8 48 89 ef 58 5d e9 74 47 0c f8 e8 9f 77 2d f8 eb c9 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 54 <55> 48 89 fd 9c 41 5c fa 41 f7 c4 00 02 00 00 75 36 bf 01 00 00 00 RSP: 0018:ffffc90000147c60 EFLAGS: 00000202 RAX: 0000000000002a68 RBX: 00000000000bed40 RCX: 0000000000000000 RDX: 61c8864680b583eb RSI: ffffffff89adcbe0 RDI: ffffffff90598048 RBP: ffffffff90598040 R08: ffffffff90598048 R09: 0000000000000001 R10: ffffffff817f77e8 R11: 0000000000000001 R12: dffffc0000000000 R13: ffffffff89adcbe0 R14: 1ffff92000028f90 R15: ffff88801c4aa450 debug_object_deactivate lib/debugobjects.c:735 [inline] debug_object_deactivate+0x101/0x300 lib/debugobjects.c:723 debug_rcu_head_unqueue kernel/rcu/rcu.h:197 [inline] rcu_do_batch kernel/rcu/tree.c:2554 [inline] rcu_core+0x769/0x1880 kernel/rcu/tree.c:2812 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 18 31 sbb %dh,(%rcx) 2: d2 31 shlb %cl,(%rcx) 4: f6 e8 imul %al 6: 6e outsb %ds:(%rsi),(%dx) 7: d3 0b rorl %cl,(%rbx) 9: f8 clc a: 48 89 ef mov %rbp,%rdi d: 58 pop %rax e: 5d pop %rbp f: e9 74 47 0c f8 jmpq 0xf80c4788 14: e8 9f 77 2d f8 callq 0xf82d77b8 19: eb c9 jmp 0xffffffe4 1b: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 22: 00 00 00 00 26: 66 90 xchg %ax,%ax 28: 41 54 push %r12 * 2a: 55 push %rbp <-- trapping instruction 2b: 48 89 fd mov %rdi,%rbp 2e: 9c pushfq 2f: 41 5c pop %r12 31: fa cli 32: 41 f7 c4 00 02 00 00 test $0x200,%r12d 39: 75 36 jne 0x71 3b: bf 01 00 00 00 mov $0x1,%edi