Hello, syzbot found the following issue on: HEAD commit: 547ab8fc4cb0 Merge tag 'loongarch-fixes-6.8-2' of git://gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=152495b7e80000 kernel config: https://syzkaller.appspot.com/x/.config?x=3d64aaed894826fe dashboard link: https://syzkaller.appspot.com/bug?extid=393d0ef63475d9bb1f16 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/8c5365601400/disk-547ab8fc.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/ca4bf951cebe/vmlinux-547ab8fc.xz kernel image: https://storage.googleapis.com/syzbot-assets/8a0ae7827471/bzImage-547ab8fc.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+393d0ef63475d9bb1f16@xxxxxxxxxxxxxxxxxxxxxxxxx ======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-rc3-syzkaller-00041-g547ab8fc4cb0 #0 Not tainted -------------------------------------------------------- kworker/u4:7/1097 just changed the state of lock: ffffffff8ec04eb8 (disc_data_lock#2){.?..}-{2:2}, at: ap_get drivers/net/ppp/ppp_async.c:136 [inline] ffffffff8ec04eb8 (disc_data_lock#2){.?..}-{2:2}, at: ppp_asynctty_receive+0x40/0x2000 drivers/net/ppp/ppp_async.c:335 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#2); local_irq_disable(); lock(&port_lock_key); lock(disc_data_lock#2); <Interrupt> lock(&port_lock_key); *** DEADLOCK *** 4 locks held by kworker/u4:7/1097: #0: ffff888014c8d938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c8d938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90004e97d20 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90004e97d20 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffff88803d92b0b8 (&buf->lock){+.+.}-{3:3}, at: flush_to_ldisc+0x38/0x860 drivers/tty/tty_buffer.c:466 #3: ffff8880751ac0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x80 drivers/tty/tty_ldisc.c:263 the shortest dependencies between 2nd lock and 1st lock: -> (&port_lock_key){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:616 [inline] serial8250_handle_irq+0x81/0x710 drivers/tty/serial/8250/8250_port.c:1913 serial8250_default_handle_irq+0xd1/0x1f0 drivers/tty/serial/8250/8250_port.c:1962 serial8250_interrupt+0xa9/0x1f0 drivers/tty/serial/8250/8250_core.c:127 __handle_irq_event_percpu+0x289/0xa30 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x89/0x1f0 kernel/irq/handle.c:210 handle_edge_irq+0x25f/0xc20 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:161 [inline] handle_irq arch/x86/kernel/irq.c:238 [inline] __common_interrupt+0x138/0x230 arch/x86/kernel/irq.c:257 common_interrupt+0xa5/0xd0 arch/x86/kernel/irq.c:247 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:640 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] uart_port_unlock_irqrestore include/linux/serial_core.h:667 [inline] serial_port_runtime_resume+0x204/0x2b0 drivers/tty/serial/serial_port.c:41 __rpm_callback+0x2df/0x790 drivers/base/power/runtime.c:393 rpm_callback drivers/base/power/runtime.c:447 [inline] rpm_resume+0x10b1/0x1af0 drivers/base/power/runtime.c:913 pm_runtime_work+0x147/0x210 drivers/base/power/runtime.c:978 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 IN-SOFTIRQ-W at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:616 [inline] serial8250_console_write+0x1a8/0x1840 drivers/tty/serial/8250/8250_port.c:3403 console_emit_next_record kernel/printk/printk.c:2901 [inline] console_flush_all+0x808/0xec0 kernel/printk/printk.c:2967 console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3036 vprintk_emit+0x508/0x720 kernel/printk/printk.c:2303 dev_vprintk_emit+0x2ae/0x330 drivers/base/core.c:4850 dev_printk_emit+0xdd/0x120 drivers/base/core.c:4861 _dev_err+0x122/0x170 drivers/base/core.c:4916 __usb_hcd_giveback_urb+0x373/0x530 drivers/usb/core/hcd.c:1650 dummy_timer+0x8aa/0x3220 drivers/usb/gadget/udc/dummy_hcd.c:1987 call_timer_fn+0x17e/0x600 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x621/0x830 kernel/time/timer.c:2038 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2051 __do_softirq+0x2bb/0x942 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu+0xf1/0x1c0 kernel/softirq.c:632 irq_exit_rcu+0x9/0x30 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x97/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 xt_obj_to_user+0xeb/0x130 net/netfilter/x_tables.c:301 xt_compat_target_to_user+0x17e/0x3a0 net/netfilter/x_tables.c:1166 compat_copy_entry_to_user net/ipv6/netfilter/ip6_tables.c:1258 [inline] compat_copy_entries_to_user+0x34b/0x680 net/ipv6/netfilter/ip6_tables.c:1569 compat_get_entries net/ipv6/netfilter/ip6_tables.c:1605 [inline] do_ip6t_get_ctl+0xe46/0x1820 net/ipv6/netfilter/ip6_tables.c:1666 nf_getsockopt+0x299/0x2c0 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x263/0x380 net/ipv6/ipv6_sockglue.c:1488 tcp_getsockopt+0x163/0x1c0 net/ipv4/tcp.c:4372 do_sock_getsockopt+0x373/0x850 net/socket.c:2373 __sys_getsockopt+0x270/0x330 net/socket.c:2402 __do_compat_sys_socketcall net/compat.c:494 [inline] __se_compat_sys_socketcall+0x348/0x1430 net/compat.c:423 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbd/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 INITIAL USE at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:616 [inline] serial8250_do_set_termios+0x531/0x17e0 drivers/tty/serial/8250/8250_port.c:2793 uart_set_options+0x3eb/0x730 drivers/tty/serial/serial_core.c:2320 serial8250_console_setup+0x3db/0x670 drivers/tty/serial/8250/8250_port.c:3507 univ8250_console_setup+0x3ac/0x470 drivers/tty/serial/8250/8250_core.c:632 try_enable_preferred_console+0x40d/0x560 kernel/printk/printk.c:3302 register_console+0x261/0xcd0 kernel/printk/printk.c:3479 univ8250_console_init+0x49/0x50 drivers/tty/serial/8250/8250_core.c:717 console_init+0x198/0x680 kernel/printk/printk.c:3688 start_kernel+0x2d2/0x500 init/main.c:1008 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x99/0xa0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x171/0x17b } ... key at: [<ffffffff947ae860>] port_lock_key+0x0/0x20 ... acquired at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 ap_get drivers/net/ppp/ppp_async.c:136 [inline] ppp_asynctty_wakeup+0x20/0x210 drivers/net/ppp/ppp_async.c:352 tty_wakeup+0xbb/0x100 drivers/tty/tty_io.c:523 tty_port_default_wakeup+0xa6/0xf0 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x6ad/0x8a0 drivers/tty/serial/8250/8250_port.c:1835 __start_tx+0x32e/0x470 drivers/tty/serial/8250/8250_port.c:1544 serial_port_runtime_resume+0x1f0/0x2b0 drivers/tty/serial/serial_port.c:40 __rpm_callback+0x2df/0x790 drivers/base/power/runtime.c:393 rpm_callback drivers/base/power/runtime.c:447 [inline] rpm_resume+0x10b1/0x1af0 drivers/base/power/runtime.c:913 pm_runtime_work+0x147/0x210 drivers/base/power/runtime.c:978 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 -> (disc_data_lock#2){.?..}-{2:2} { IN-HARDIRQ-R at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 ap_get drivers/net/ppp/ppp_async.c:136 [inline] ppp_asynctty_wakeup+0x20/0x210 drivers/net/ppp/ppp_async.c:352 tty_wakeup+0xbb/0x100 drivers/tty/tty_io.c:523 tty_port_default_wakeup+0xa6/0xf0 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x6ad/0x8a0 drivers/tty/serial/8250/8250_port.c:1835 serial8250_handle_irq+0x558/0x710 drivers/tty/serial/8250/8250_port.c:1942 serial8250_default_handle_irq+0xd1/0x1f0 drivers/tty/serial/8250/8250_port.c:1962 serial8250_interrupt+0xa9/0x1f0 drivers/tty/serial/8250/8250_core.c:127 __handle_irq_event_percpu+0x289/0xa30 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x89/0x1f0 kernel/irq/handle.c:210 handle_edge_irq+0x25f/0xc20 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:161 [inline] handle_irq arch/x86/kernel/irq.c:238 [inline] __common_interrupt+0x138/0x230 arch/x86/kernel/irq.c:257 common_interrupt+0xa5/0xd0 arch/x86/kernel/irq.c:247 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:640 obj_cgroup_charge+0x34e/0x630 __memcg_slab_pre_alloc_hook+0x28d/0x2b0 mm/slub.c:1929 memcg_slab_pre_alloc_hook mm/slub.c:1950 [inline] slab_pre_alloc_hook mm/slub.c:3766 [inline] slab_alloc_node mm/slub.c:3842 [inline] kmem_cache_alloc+0x202/0x340 mm/slub.c:3867 vm_area_dup+0x27/0x290 kernel/fork.c:480 dup_mmap kernel/fork.c:695 [inline] dup_mm kernel/fork.c:1685 [inline] copy_mm+0xd94/0x21b0 kernel/fork.c:1734 copy_process+0x1d73/0x3fc0 kernel/fork.c:2497 kernel_clone+0x21d/0x8d0 kernel/fork.c:2902 __do_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:254 [inline] __se_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:240 [inline] __ia32_compat_sys_ia32_clone+0x255/0x2a0 arch/x86/kernel/sys_ia32.c:240 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbd/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 HARDIRQ-ON-R at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 ap_get drivers/net/ppp/ppp_async.c:136 [inline] ppp_asynctty_receive+0x40/0x2000 drivers/net/ppp/ppp_async.c:335 tty_ldisc_receive_buf+0x11f/0x170 drivers/tty/tty_buffer.c:390 tty_port_default_receive_buf+0x6d/0xa0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:444 [inline] flush_to_ldisc+0x328/0x860 drivers/tty/tty_buffer.c:494 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 INITIAL USE at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:326 ppp_asynctty_close+0x29/0x190 drivers/net/ppp/ppp_async.c:219 tty_ldisc_kill+0xa3/0x1a0 drivers/tty/tty_ldisc.c:607 tty_ldisc_release+0x1a1/0x200 drivers/tty/tty_ldisc.c:775 tty_release_struct+0x2b/0xe0 drivers/tty/tty_io.c:1696 tty_release+0xd0c/0x12c0 drivers/tty/tty_io.c:1867 __fput+0x429/0x8a0 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close fs/open.c:1539 [inline] __ia32_sys_close+0x7e/0x110 fs/open.c:1539 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbd/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 INITIAL READ USE at: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 ap_get drivers/net/ppp/ppp_async.c:136 [inline] ppp_asynctty_wakeup+0x20/0x210 drivers/net/ppp/ppp_async.c:352 tty_wakeup+0xbb/0x100 drivers/tty/tty_io.c:523 tty_port_default_wakeup+0xa6/0xf0 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x6ad/0x8a0 drivers/tty/serial/8250/8250_port.c:1835 __start_tx+0x32e/0x470 drivers/tty/serial/8250/8250_port.c:1544 serial_port_runtime_resume+0x1f0/0x2b0 drivers/tty/serial/serial_port.c:40 __rpm_callback+0x2df/0x790 drivers/base/power/runtime.c:393 rpm_callback drivers/base/power/runtime.c:447 [inline] rpm_resume+0x10b1/0x1af0 drivers/base/power/runtime.c:913 pm_runtime_work+0x147/0x210 drivers/base/power/runtime.c:978 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 } ... key at: [<ffffffff8ec04eb8>] disc_data_lock+0x18/0x60 ... acquired at: mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 mark_usage kernel/locking/lockdep.c:4579 [inline] __lock_acquire+0x10e0/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 ap_get drivers/net/ppp/ppp_async.c:136 [inline] ppp_asynctty_receive+0x40/0x2000 drivers/net/ppp/ppp_async.c:335 tty_ldisc_receive_buf+0x11f/0x170 drivers/tty/tty_buffer.c:390 tty_port_default_receive_buf+0x6d/0xa0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:444 [inline] flush_to_ldisc+0x328/0x860 drivers/tty/tty_buffer.c:494 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 stack backtrace: CPU: 1 PID: 1097 Comm: kworker/u4:7 Not tainted 6.8.0-rc3-syzkaller-00041-g547ab8fc4cb0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: events_unbound flush_to_ldisc Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 mark_lock_irq+0x867/0xc20 kernel/locking/lockdep.c:4236 mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 mark_usage kernel/locking/lockdep.c:4579 [inline] __lock_acquire+0x10e0/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 ap_get drivers/net/ppp/ppp_async.c:136 [inline] ppp_asynctty_receive+0x40/0x2000 drivers/net/ppp/ppp_async.c:335 tty_ldisc_receive_buf+0x11f/0x170 drivers/tty/tty_buffer.c:390 tty_port_default_receive_buf+0x6d/0xa0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:444 [inline] flush_to_ldisc+0x328/0x860 drivers/tty/tty_buffer.c:494 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 </TASK> --- 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@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
