======================================================== WARNING: possible irq lock inversion dependency detected 6.5.0-rc5-syzkaller-00053-g13b937206866 #0 Not tainted -------------------------------------------------------- syz-executor.0/5659 just changed the state of lock: ffffffff8d9472f8 (disc_data_lock){.?..}-{2:2}, at: ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:136 but this lock was taken by another, HARDIRQ-safe lock in the past: (&port_lock_key){-.-.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(disc_data_lock); local_irq_disable(); lock(&port_lock_key); lock(disc_data_lock); lock(&port_lock_key); *** DEADLOCK *** 1 lock held by syz-executor.0/5659: #0: ffff8880938dd098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 the shortest dependencies between 2nd lock and 1st lock: -> (&port_lock_key){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 serial8250_handle_irq+0x91/0xbe0 drivers/tty/serial/8250/8250_port.c:1917 serial8250_default_handle_irq+0x94/0x210 drivers/tty/serial/8250/8250_port.c:1963 serial8250_interrupt+0xfc/0x200 drivers/tty/serial/8250/8250_core.c:127 __handle_irq_event_percpu+0x22a/0x740 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x261/0xcf0 kernel/irq/chip.c:834 generic_handle_irq_desc include/linux/irqdesc.h:161 [inline] handle_irq arch/x86/kernel/irq.c:238 [inline] __common_interrupt+0x9f/0x220 arch/x86/kernel/irq.c:257 common_interrupt+0xa9/0xd0 arch/x86/kernel/irq.c:247 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] acpi_safe_halt+0x1b/0x20 drivers/acpi/processor_idle.c:112 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x82/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x315/0x3f0 kernel/sched/idle.c:282 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379 rest_init+0x16f/0x2b0 init/main.c:726 arch_call_rest_init+0x13/0x30 init/main.c:823 start_kernel+0x39f/0x480 init/main.c:1068 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0x167/0x16b IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 serial8250_console_write+0x57e/0x1060 drivers/tty/serial/8250/8250_port.c:3403 console_emit_next_record kernel/printk/printk.c:2877 [inline] console_flush_all+0x4c8/0xf50 kernel/printk/printk.c:2933 console_unlock+0xc6/0x1f0 kernel/printk/printk.c:3007 vprintk_emit+0x1c5/0x640 kernel/printk/printk.c:2307 dev_vprintk_emit drivers/base/core.c:4840 [inline] dev_printk_emit+0xfb/0x140 drivers/base/core.c:4851 __dev_printk+0xf5/0x270 drivers/base/core.c:4863 _dev_warn+0xe5/0x120 drivers/base/core.c:4907 usb_rx_callback_intf0+0x11c/0x1a0 drivers/media/rc/imon.c:1771 __usb_hcd_giveback_urb+0x359/0x5c0 drivers/usb/core/hcd.c:1671 usb_hcd_giveback_urb+0x389/0x430 drivers/usb/core/hcd.c:1754 dummy_timer+0x1415/0x35f0 drivers/usb/gadget/udc/dummy_hcd.c:1987 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x764/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x218/0x965 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 _compound_head include/linux/page-flags.h:245 [inline] virt_to_head_page include/linux/mm.h:1204 [inline] virt_to_slab mm/kasan/../slab.h:213 [inline] kasan_addr_to_slab+0x3c/0x80 mm/kasan/common.c:36 __kasan_record_aux_stack+0xe/0xd0 mm/kasan/generic.c:477 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2649 dentry_free+0xc2/0x160 fs/dcache.c:377 __dentry_kill+0x4c1/0x640 fs/dcache.c:621 dentry_kill fs/dcache.c:745 [inline] dput+0x703/0xfd0 fs/dcache.c:913 lookup_fast+0x275/0x520 fs/namei.c:1656 walk_component+0x5b/0x5a0 fs/namei.c:1994 link_path_walk.part.0.constprop.0+0x71f/0xce0 fs/namei.c:2325 link_path_walk fs/namei.c:2250 [inline] path_openat+0x231/0x29c0 fs/namei.c:3789 do_filp_open+0x1de/0x430 fs/namei.c:3820 do_sys_openat2+0x176/0x1e0 fs/open.c:1407 do_sys_open fs/open.c:1422 [inline] __do_sys_openat fs/open.c:1438 [inline] __se_sys_openat fs/open.c:1433 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1433 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 serial8250_do_set_termios+0x334/0x1240 drivers/tty/serial/8250/8250_port.c:2794 serial8250_set_termios+0x6b/0x80 drivers/tty/serial/8250/8250_port.c:2913 uart_set_options+0x30e/0x5e0 drivers/tty/serial/serial_core.c:2284 serial8250_console_setup+0x18a/0x430 drivers/tty/serial/8250/8250_port.c:3507 univ8250_console_setup+0x168/0x210 drivers/tty/serial/8250/8250_core.c:631 try_enable_preferred_console+0x24d/0x470 kernel/printk/printk.c:3228 register_console+0x331/0x10d0 kernel/printk/printk.c:3401 univ8250_console_init+0x35/0x50 drivers/tty/serial/8250/8250_core.c:716 console_init+0xba/0x5c0 kernel/printk/printk.c:3601 start_kernel+0x25a/0x480 init/main.c:1004 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0x167/0x16b } ... key at: [] port_lock_key+0x0/0x40 ... acquired at: __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:136 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:360 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:525 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x542/0xf60 drivers/tty/serial/8250/8250_port.c:1839 __start_tx drivers/tty/serial/8250/8250_port.c:1547 [inline] serial8250_start_tx+0x7a8/0x980 drivers/tty/serial/8250/8250_port.c:1656 serial_port_runtime_resume+0x29e/0x330 drivers/tty/serial/serial_port.c:40 __rpm_callback+0xc5/0x4c0 drivers/base/power/runtime.c:392 rpm_callback+0x1da/0x220 drivers/base/power/runtime.c:446 rpm_resume+0xdb9/0x1980 drivers/base/power/runtime.c:912 pm_runtime_work+0x12e/0x180 drivers/base/power/runtime.c:977 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 -> (disc_data_lock){.?..}-{2:2} { IN-HARDIRQ-R at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x3a/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:136 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:360 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:525 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x542/0xf60 drivers/tty/serial/8250/8250_port.c:1839 serial8250_handle_irq+0x5fb/0xbe0 drivers/tty/serial/8250/8250_port.c:1943 serial8250_default_handle_irq+0x94/0x210 drivers/tty/serial/8250/8250_port.c:1963 serial8250_interrupt+0xfc/0x200 drivers/tty/serial/8250/8250_core.c:127 __handle_irq_event_percpu+0x22a/0x740 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x261/0xcf0 kernel/irq/chip.c:834 generic_handle_irq_desc include/linux/irqdesc.h:161 [inline] handle_irq arch/x86/kernel/irq.c:238 [inline] __common_interrupt+0x9f/0x220 arch/x86/kernel/irq.c:257 common_interrupt+0xa9/0xd0 arch/x86/kernel/irq.c:247 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636 check_kcov_mode kernel/kcov.c:175 [inline] write_comp_data+0x3c/0x90 kernel/kcov.c:236 in_aton+0xa0/0x150 net/core/utils.c:61 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:764 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x53b/0xc70 drivers/net/netdevsim/dev.c:850 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:136 ppp_asynctty_ioctl+0x23/0x2c0 drivers/net/ppp/ppp_async.c:286 tty_ioctl+0x706/0x1580 drivers/tty/tty_io.c:2795 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 ppp_asynctty_close+0x1c/0x1c0 drivers/net/ppp/ppp_async.c:219 tty_ldisc_close+0x111/0x190 drivers/tty/tty_ldisc.c:455 tty_ldisc_kill+0x94/0x150 drivers/tty/tty_ldisc.c:607 tty_ldisc_release+0x17b/0x2a0 drivers/tty/tty_ldisc.c:775 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1698 tty_release+0xe23/0x1410 drivers/tty/tty_io.c:1869 __fput+0x3f7/0xac0 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:136 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:360 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:525 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x542/0xf60 drivers/tty/serial/8250/8250_port.c:1839 __start_tx drivers/tty/serial/8250/8250_port.c:1547 [inline] serial8250_start_tx+0x7a8/0x980 drivers/tty/serial/8250/8250_port.c:1656 serial_port_runtime_resume+0x29e/0x330 drivers/tty/serial/serial_port.c:40 __rpm_callback+0xc5/0x4c0 drivers/base/power/runtime.c:392 rpm_callback+0x1da/0x220 drivers/base/power/runtime.c:446 rpm_resume+0xdb9/0x1980 drivers/base/power/runtime.c:912 pm_runtime_work+0x12e/0x180 drivers/base/power/runtime.c:977 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 } ... key at: [] disc_data_lock+0x18/0x60 ... acquired at: mark_usage kernel/locking/lockdep.c:4586 [inline] __lock_acquire+0x13a5/0x5de0 kernel/locking/lockdep.c:5098 lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:136 ppp_asynctty_ioctl+0x23/0x2c0 drivers/net/ppp/ppp_async.c:286 tty_ioctl+0x706/0x1580 drivers/tty/tty_io.c:2795 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd stack backtrace: CPU: 1 PID: 5659 Comm: syz-executor.0 Not tainted 6.5.0-rc5-syzkaller-00053-g13b937206866 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_irq_inversion_bug.part.0+0x3e1/0x590 kernel/locking/lockdep.c:4087 print_irq_inversion_bug kernel/locking/lockdep.c:4040 [inline] check_usage_forwards kernel/locking/lockdep.c:4118 [inline] mark_lock_irq kernel/locking/lockdep.c:4250 [inline] mark_lock+0x920/0x1950 kernel/locking/lockdep.c:4685 mark_usage kernel/locking/lockdep.c:4586 [inline] __lock_acquire+0x13a5/0x5de0 kernel/locking/lockdep.c:5098 lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:136 ppp_asynctty_ioctl+0x23/0x2c0 drivers/net/ppp/ppp_async.c:286 tty_ioctl+0x706/0x1580 drivers/tty/tty_io.c:2795 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f4b7d07cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4b7dcf10c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4b7d19bf80 RCX: 00007f4b7d07cae9 RDX: 0000000000000000 RSI: 000000000000540b RDI: 0000000000000006 RBP: 00007f4b7d0c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f4b7d19bf80 R15: 00007f4b7d2bfa48