INFO: task kworker/0:6:11766 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:6 state:D stack:22256 pid:11766 tgid:11766 ppid:2 flags:0x00004000 Workqueue: events fqdir_free_fn Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2557 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3de/0x5f0 kernel/sched/completion.c:116 rcu_barrier+0x323/0x6c0 kernel/rcu/tree.c:4554 fqdir_free_fn+0x32/0x130 net/ipv4/inet_fragment.c:167 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 5 locks held by kworker/1:1/37: #0: ffff888105ebad48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc90000277d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff888109749190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff888109749190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff888101353190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff888101353190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2295 #4: ffff888100abc148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_remove+0x71/0xa0 fs/kernfs/dir.c:1527 5 locks held by kworker/1:2/805: 2 locks held by getty/2606: #0: ffff88811420a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 1 lock held by udevd/4901: #0: ffff888100abc148 (&root->kernfs_rwsem){++++}-{3:3} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 4 locks held by udevd/4911: #0: ffff888127387b08 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xde/0x12c0 fs/seq_file.c:182 #1: ffff88811393d088 (&of->mutex#2){+.+.}-{3:3} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88812a9d30f8 (kn->active#23){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811eeeb190 ( &dev->mutex ){....}-{3:3} , at: device_lock_interruptible include/linux/device.h:1014 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 1 lock held by udevd/4956: #0: ffff888100abc148 ( &root->kernfs_rwsem){++++}-{3:3} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 7 locks held by kworker/1:5/5054: 5 locks held by kworker/1:6/5415: 2 locks held by kworker/u8:0/7446: #0: ffff888100089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc90011437d80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 5 locks held by kworker/1:3/13626: 1 lock held by syz-executor/14073: #0: ffffffff88ec6df8 ( rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:328 1 lock held by syz.1.3051/17802: #0: ffffffff88ec6df8 ( rcu_state.exp_mutex){+.+.}-{3:3} , at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:328 1 lock held by syz.0.3053/17800: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{3:3} , at: kernfs_remove_by_name_ns+0x87/0x130 fs/kernfs/dir.c:1689 1 lock held by syz.4.3054/17786: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{3:3} , at: kernfs_remove_by_name_ns+0x87/0x130 fs/kernfs/dir.c:1689 1 lock held by modprobe/17798: #0: ffff888100abc148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 1 lock held by syz-executor/17804: #0: ffff888100abc148 (&root->kernfs_rwsem){++++}-{3:3} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 1 lock held by syz-executor/17806: #0: ffff888100abc148 ( &root->kernfs_rwsem ){++++}-{3:3}, at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 1 lock held by syz-executor/17807: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{3:3} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 1 lock held by syz-executor/17808: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{3:3} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 1 lock held by syz-executor/17809: #0: ffff888100abc148 ( &root->kernfs_rwsem ){++++}-{3:3} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: imon 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5054 Comm: kworker/1:5 Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: events_power_efficient gc_worker RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:413 Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 61 ed 0e ff eb a0 e8 ea ed 0e RSP: 0018:ffffc900001b8590 EFLAGS: 00000002 RAX: 0000000000000020 RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff829bdec5 RDI: ffffffff935cfbc0 RBP: ffffffff935cfb80 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000020 R14: ffffffff829bde60 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f5900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe1c8aae6c CR3: 0000000115a40000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_out drivers/tty/serial/8250/8250.h:142 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3322 [inline] serial8250_console_write+0xce7/0x1090 drivers/tty/serial/8250/8250_port.c:3393 console_emit_next_record kernel/printk/printk.c:2983 [inline] console_flush_all+0x53c/0xd70 kernel/printk/printk.c:3049 console_unlock+0xae/0x290 kernel/printk/printk.c:3118 vprintk_emit+0x409/0x600 kernel/printk/printk.c:2348 dev_vprintk_emit drivers/base/core.c:4912 [inline] dev_printk_emit+0xfb/0x140 drivers/base/core.c:4923 __dev_printk+0xf5/0x270 drivers/base/core.c:4935 _dev_warn+0xe5/0x120 drivers/base/core.c:4979 usb_rx_callback_intf0+0x11c/0x1a0 drivers/media/rc/imon.c:1768 __usb_hcd_giveback_urb+0x389/0x6e0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x396/0x450 drivers/usb/core/hcd.c:1734 dummy_timer+0x17c3/0x38d0 drivers/usb/gadget/udc/dummy_hcd.c:1988 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x20c/0xcc0 kernel/time/hrtimer.c:1753 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1770 handle_softirqs+0x209/0x8e0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0xac/0x110 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1043 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:345 [inline] RIP: 0010:gc_worker+0x2e1/0x1760 net/netfilter/nf_conntrack_core.c:1488 Code: 00 00 48 c7 c7 88 9f 53 8a e8 5b 4d 37 fb 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 89 1b 59 fb 48 85 db 58 0f 85 3d 10 00 00 0a 19 59 fb eb 07 e8 03 19 59 fb f3 90 44 8b 35 ea 24 58 04 31 RSP: 0018:ffffc9000ee97bc8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff85fb863a RDX: ffff88810f311d40 RSI: ffffffff85fb8649 RDI: 0000000000000007 RBP: ffff888111000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000001a85 R13: dffffc0000000000 R14: 0000000000003509 R15: 0000000000040000 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244