INFO: task kworker/u4:8:3931 blocked for more than 143 seconds. Not tainted 6.1.108-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:8 state:D stack:21792 pid:3931 ppid:2 flags:0x00004000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0xac/0x300 kernel/time/timer.c:1941 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x350/0x610 kernel/sched/completion.c:138 __synchronize_srcu+0x2b7/0x360 kernel/rcu/srcutree.c:1243 fsnotify_mark_destroy_workfn+0x142/0x340 fs/notify/mark.c:898 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task kworker/u4:12:4143 blocked for more than 143 seconds. Not tainted 6.1.108-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:12 state:D stack:22200 pid:4143 ppid:2 flags:0x00004000 Workqueue: events_unbound fsnotify_connector_destroy_workfn Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0xac/0x300 kernel/time/timer.c:1941 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x350/0x610 kernel/sched/completion.c:138 __synchronize_srcu+0x2b7/0x360 kernel/rcu/srcutree.c:1243 fsnotify_connector_destroy_workfn+0x40/0xa0 fs/notify/mark.c:208 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Showing all locks held in the system: 1 lock held by kthreadd/2: #0: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:1/11: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90000107d20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b190 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b990 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 3 locks held by kworker/u4:2/34: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90000ab7d20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:4/56: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90001577d20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 1 lock held by dhcpcd/3305: #0: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 2 locks held by getty/3392: #0: ffff88802f11e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 6 locks held by kworker/0:3/3680: 3 locks held by kworker/u4:5/3690: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004837d20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:6/3694: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004807d20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 2 locks held by kworker/u4:8/3931: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90005407d20 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 3 locks held by kworker/u4:9/3933: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000563fd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:10/3934: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000523fd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:11/4065: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90005eafd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 2 locks held by kworker/u4:12/4143: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000b40fd20 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 3 locks held by kworker/u4:13/4144: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000b41fd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:14/4164: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000b50fd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:15/4305: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000315fd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:0/8570: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000391fd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 3 locks held by kworker/u4:7/11234: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900035bfd20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x241c/0x4060 kernel/fork.c:2371 4 locks held by udevd/12958: #0: ffff888050ebde80 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182 #1: ffff88806955ac88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4f/0x3a0 fs/kernfs/file.c:154 #2: ffff88804e7a7748 (kn->active#33){.+.+}-{0:0}, at: kernfs_seq_start+0x6e/0x3a0 fs/kernfs/file.c:155 #3: ffff888078a63190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:842 [inline] #3: ffff888078a63190 (&dev->mutex){....}-{3:3}, at: serial_show+0x22/0x90 drivers/usb/core/sysfs.c:142 6 locks held by kworker/0:20/12984: 1 lock held by syz.2.1240/13640: 1 lock held by syz.1.1241/13645: 2 locks held by syz.4.1239/13648: 1 lock held by syz-executor/13650: #0: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x69f/0x26a0 kernel/exit.c:827 6 locks held by syz-executor/13651: 4 locks held by syz-executor/13991: #0: ffff88807fb00460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580 #1: ffff88803127c888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325 #2: ffff888027d5c748 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8de22608 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1ad/0x800 drivers/net/netdevsim/bus.c:160 4 locks held by syz-executor/13993: #0: ffff88807fb00460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580 #1: ffff888031206888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325 #2: ffff888027d5c830 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8de22608 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf8/0x480 drivers/net/netdevsim/bus.c:209 7 locks held by syz-executor/14001: #0: ffff88807fb00460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580 #1: ffff88803118d088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325 #2: ffff888027d5c830 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8de22608 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf8/0x480 drivers/net/netdevsim/bus.c:209 #4: ffff888024f2d0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #4: ffff888024f2d0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline] #4: ffff888024f2d0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb6/0x880 drivers/base/dd.c:1283 #5: ffff888024f2a2f8 (&devlink->lock_key#23){+.+.}-{3:3}, at: nsim_drv_remove+0x54/0x160 drivers/net/netdevsim/dev.c:1674 #6: ffffffff8d330480 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5f0 kernel/rcu/tree.c:4019 4 locks held by syz-executor/14002: #0: ffff88807fb00460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580 #1: ffff888031278c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325 #2: ffff888027d5c830 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8de22608 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf8/0x480 drivers/net/netdevsim/bus.c:209 1 lock held by kworker/u4:4/15272: #0: ffffffff8d3538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x69f/0x26a0 kernel/exit.c:827 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.108-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ae/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 13648 Comm: syz.4.1239 Not tainted 6.1.108-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:check_preemption_disabled+0x63/0x110 lib/smp_processor_id.c:19 Code: 44 24 08 0f 85 c7 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 <74> c9 49 89 f6 49 89 ff 65 4c 8b 25 1d cb 5b 75 41 f6 44 24 2f 04 RSP: 0018:ffffc90005fd7ba0 EFLAGS: 00000046 RAX: 0000000080000000 RBX: 0000000000000000 RCX: ffff888060a45940 RDX: 0000000000000000 RSI: ffffffff8b0c13e0 RDI: ffffffff8b5d69c0 RBP: 0000000000000000 R08: ffffffff81cdea6c R09: ffffc90005fd7dc0 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246 R13: ffff888060a45940 R14: 00000000ffffffff R15: ffffffff8d32af40 FS: 00007f5c866696c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c323726 CR3: 000000002a098000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] lock_is_held_type+0xfd/0x180 kernel/locking/lockdep.c:5706 lock_is_held include/linux/lockdep.h:283 [inline] __might_resched+0xf0/0x780 kernel/sched/core.c:9917 __might_fault+0x69/0x110 mm/memory.c:5831 _copy_from_user+0x26/0x170 lib/usercopy.c:14 copy_from_user include/linux/uaccess.h:161 [inline] restore_altstack+0x95/0x150 kernel/signal.c:4256 __do_sys_rt_sigreturn+0x19d/0x250 arch/x86/kernel/signal.c:678 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5c8577cef7 Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 RSP: 002b:00007f5c866690e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007f5c85935f88 RCX: 00007f5c8577cef9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5c85935f88 RBP: 00007f5c85935f80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5c85935f8c R13: 0000000000000000 R14: 00007ffcce5aeba0 R15: 00007ffcce5aec88