INFO: task kworker/1:1:38 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00105-gab6dc9a6c721 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:1 state:D stack:21304 pid:38 tgid:38 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events kernfs_notify_workfn Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x132a/0x3b00 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x62f/0xb60 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0xef/0x480 kernel/locking/rwsem.c:1526 kernfs_notify_workfn+0xff/0xb20 fs/kernfs/file.c:914 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff890c2840 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:841 [inline] , at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 3 locks held by kworker/1:1/38: 3 locks held by kworker/1:2/1118: 1 lock held by udevd/2842: 2 locks held by getty/2904: #0: ffff888108b9f0a0 (&tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 ( &ldata->atomic_read_lock){+.+.}-{4:4} , at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/2951: 1 lock held by syz-executor/2952: #0: ffffffff890cdd78 ( rcu_state.exp_mutex){+.+.}-{4:4} , at: exp_funnel_lock+0x280/0x3c0 kernel/rcu/tree_exp.h:304 1 lock held by syz-executor/2955: 1 lock held by syz-executor/2957: 1 lock held by syz-executor/2959: 8 locks held by kworker/0:5/5290: 3 locks held by kworker/1:6/7890: 3 locks held by kworker/0:6/8283: 2 locks held by kworker/u8:0/8911: #0: ffff888100089148 ((wq_completion)events_unbound ){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900142f7d18 ((work_completion)(&pool->idle_cull_work) ){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 1 lock held by syz-executor/10064: 1 lock held by syz-executor/10065: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00105-gab6dc9a6c721 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: yealink 4-1:36.0: urb_ctl_callback - urb status -71 yealink 4-1:36.0: urb_irq_callback - urb status -71 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5290 Comm: kworker/0:5 Not tainted 6.15.0-rc6-syzkaller-00105-gab6dc9a6c721 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Workqueue: events_power_efficient gc_worker RIP: 0010:printk_get_next_message+0x257/0x6d0 kernel/printk/printk.c:3016 Code: 75 6b e8 5c 21 20 00 0f b6 74 24 20 31 ff e8 30 1c 20 00 80 7c 24 24 00 74 53 e8 44 21 20 00 41 0f b6 47 13 8b 15 59 bc ae 07 e8 05 89 d6 89 54 24 20 0f b6 c0 89 c7 89 04 24 e8 a3 1b 20 00 RSP: 0018:ffffc90000007498 EFLAGS: 00000046 RAX: 0000000000000062 RBX: 1ffff92000000e98 RCX: ffffffff815c49f0 RDX: 000000000000000f RSI: ffffffff815c49fc RDI: 0000000000000001 RBP: ffffc900000076c8 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 00000000003c3af8 R12: 0000000000000000 R13: 0000000000000001 R14: ffffc900000074e0 R15: ffffc90000007520 FS: 0000000000000000(0000) GS:ffff8882691c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5b39c60020 CR3: 0000000123a6e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: console_emit_next_record kernel/printk/printk.c:3092 [inline] console_flush_all+0x6ea/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 dev_vprintk_emit drivers/base/core.c:4917 [inline] dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928 __dev_printk+0xf5/0x270 drivers/base/core.c:4940 _dev_err+0xe4/0x120 drivers/base/core.c:4983 urb_irq_callback+0x454/0x700 drivers/input/misc/yealink.c:418 __usb_hcd_giveback_urb+0x38a/0x6e0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1734 dummy_timer+0x180e/0x3a20 drivers/usb/gadget/udc/dummy_hcd.c:1994 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x205/0x8d0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline] RIP: 0010:nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:333 [inline] RIP: 0010:gc_worker+0x2d5/0x16d0 net/netfilter/nf_conntrack_core.c:1534 Code: 00 00 48 c7 c7 08 07 79 8a e8 17 7b 20 fb 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 45 5b 43 fb 58 48 85 db 0f 85 d0 0f 00 00 c6 5f 43 fb 8b 1d 80 fb 3f 04 41 89 dc 31 ff 41 83 e4 01 44 89 RSP: 0018:ffffc90003ed7b60 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff863916b9 RDX: ffff8881220b0000 RSI: ffffffff863916c8 RDI: 0000000000000007 RBP: ffffffff93a2efec R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888112200000 R13: 0000000000040000 R14: dffffc0000000000 R15: 0000000000001770 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245