INFO: task kworker/u4:2:38 blocked for more than 143 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:2 D25392 38 2 0x80004000 Workqueue: events_unbound fsnotify_connector_destroy_workfn Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_timeout+0x43/0x250 kernel/time/timer.c:1874 mark_held_locks kernel/locking/lockdep.c:3628 [inline] __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x4a4/0x8a0 kernel/locking/lockdep.c:3702 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x1f/0x80 kernel/locking/spinlock.c:199 do_wait_for_common+0x232/0x370 kernel/sched/completion.c:85 console_conditional_schedule+0x30/0x30 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x43/0x50 kernel/sched/completion.c:138 __synchronize_srcu+0x1ba/0x240 kernel/rcu/srcutree.c:922 rcu_read_lock_any_held+0x1a0/0x1a0 arch/x86/include/asm/paravirt.h:754 fsnotify_connector_destroy_workfn+0x40/0xa0 fs/notify/mark.c:164 process_one_work+0x76e/0xfd0 kernel/workqueue.c:2268 worker_thread+0xa7f/0x1450 kernel/workqueue.c:2414 kthread+0x353/0x380 kernel/kthread.c:268 rcu_lock_release+0x20/0x20 include/linux/rcupdate.h:213 kthread_blkcg+0xd0/0xd0 kernel/kthread.c:1247 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/u4:15:2519 blocked for more than 143 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:15 D25984 2519 2 0x80004000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_timeout+0x43/0x250 kernel/time/timer.c:1874 mark_held_locks kernel/locking/lockdep.c:3628 [inline] __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x4a4/0x8a0 kernel/locking/lockdep.c:3702 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x1f/0x80 kernel/locking/spinlock.c:199 do_wait_for_common+0x232/0x370 kernel/sched/completion.c:85 console_conditional_schedule+0x30/0x30 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x43/0x50 kernel/sched/completion.c:138 __synchronize_srcu+0x1ba/0x240 kernel/rcu/srcutree.c:922 rcu_read_lock_any_held+0x1a0/0x1a0 arch/x86/include/asm/paravirt.h:754 fsnotify_mark_destroy_workfn+0xe7/0x2a0 fs/notify/mark.c:832 process_one_work+0x76e/0xfd0 kernel/workqueue.c:2268 worker_thread+0xa7f/0x1450 kernel/workqueue.c:2414 kthread+0x353/0x380 kernel/kthread.c:268 rcu_lock_release+0x20/0x20 include/linux/rcupdate.h:213 kthread_blkcg+0xd0/0xd0 kernel/kthread.c:1247 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task systemd-udevd:14846 blocked for more than 143 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D27776 14846 4110 0x80004102 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4222 __mutex_lock_common+0x129f/0x2fc0 kernel/locking/mutex.c:1033 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1118 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 eventpoll_release include/linux/eventpoll.h:61 [inline] __fput+0x5b7/0x750 fs/file_table.c:271 task_work_run+0x147/0x1d0 kernel/task_work.c:123 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x5ef/0x1f80 kernel/exit.c:795 syscall_trace_enter+0x614/0x8c0 arch/x86/entry/common.c:130 do_group_exit+0x15e/0x2c0 kernel/exit.c:893 __do_sys_exit_group+0x13/0x20 kernel/exit.c:904 __se_sys_exit_group+0x10/0x10 kernel/exit.c:902 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:902 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task systemd-udevd:14848 blocked for more than 143 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D27808 14848 4110 0x80004102 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4222 __mutex_lock_common+0x129f/0x2fc0 kernel/locking/mutex.c:1033 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1118 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 eventpoll_release include/linux/eventpoll.h:61 [inline] __fput+0x5b7/0x750 fs/file_table.c:271 task_work_run+0x147/0x1d0 kernel/task_work.c:123 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x5ef/0x1f80 kernel/exit.c:795 syscall_trace_enter+0x614/0x8c0 arch/x86/entry/common.c:130 do_group_exit+0x15e/0x2c0 kernel/exit.c:893 __do_sys_exit_group+0x13/0x20 kernel/exit.c:904 __se_sys_exit_group+0x10/0x10 kernel/exit.c:902 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:902 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task systemd-udevd:14878 blocked for more than 144 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D27408 14878 4110 0x80004102 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4222 __mutex_lock_common+0x129f/0x2fc0 kernel/locking/mutex.c:1033 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1118 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 eventpoll_release include/linux/eventpoll.h:61 [inline] __fput+0x5b7/0x750 fs/file_table.c:271 task_work_run+0x147/0x1d0 kernel/task_work.c:123 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x5ef/0x1f80 kernel/exit.c:795 syscall_trace_enter+0x614/0x8c0 arch/x86/entry/common.c:130 do_group_exit+0x15e/0x2c0 kernel/exit.c:893 __do_sys_exit_group+0x13/0x20 kernel/exit.c:904 __se_sys_exit_group+0x10/0x10 kernel/exit.c:902 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:902 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task systemd-udevd:14938 blocked for more than 144 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D27728 14938 4110 0x80004102 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4222 __mutex_lock_common+0x129f/0x2fc0 kernel/locking/mutex.c:1033 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1118 eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 eventpoll_release include/linux/eventpoll.h:61 [inline] __fput+0x5b7/0x750 fs/file_table.c:271 task_work_run+0x147/0x1d0 kernel/task_work.c:123 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x5ef/0x1f80 kernel/exit.c:795 syscall_trace_enter+0x614/0x8c0 arch/x86/entry/common.c:130 do_group_exit+0x15e/0x2c0 kernel/exit.c:893 __do_sys_exit_group+0x13/0x20 kernel/exit.c:904 __se_sys_exit_group+0x10/0x10 kernel/exit.c:902 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:902 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.0:15225 blocked for more than 144 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D26704 15225 7021 0x00004004 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_timeout+0x43/0x250 kernel/time/timer.c:1874 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:650 [inline] queued_spin_unlock arch/x86/include/asm/qspinlock.h:55 [inline] do_raw_spin_unlock+0x134/0x8d0 kernel/locking/spinlock_debug.c:139 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x1f/0x80 kernel/locking/spinlock.c:199 do_wait_for_common+0x232/0x370 kernel/sched/completion.c:85 console_conditional_schedule+0x30/0x30 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x43/0x50 kernel/sched/completion.c:138 __flush_work kernel/workqueue.c:3045 [inline] __cancel_work_timer+0x44d/0x5c0 kernel/workqueue.c:3132 start_flush_work+0x730/0x730 kernel/workqueue.c:3017 p9_conn_destroy net/9p/trans_fd.c:863 [inline] p9_fd_close+0x22e/0x3a0 net/9p/trans_fd.c:898 p9_client_create+0x97c/0xef0 net/9p/client.c:1069 lockdep_init_map_wait include/linux/lockdep.h:330 [inline] __raw_spin_lock_init+0x3f/0xf0 kernel/locking/spinlock_debug.c:24 v9fs_session_init+0x192/0x18f0 fs/9p/v9fs.c:406 __fs_reclaim_acquire+0x30/0x30 mm/page_alloc.c:4143 check_preemption_disabled+0x40/0x240 lib/smp_processor_id.c:16 lock_is_held include/linux/lockdep.h:406 [inline] rcu_read_lock_sched_held+0x106/0x170 kernel/rcu/update.c:121 trace_kmalloc+0xcb/0x120 include/trace/events/kmem.h:46 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] v9fs_mount+0x5c/0x810 fs/9p/vfs_super.c:120 kmem_cache_alloc_trace+0x24c/0x300 mm/slab.c:3552 v9fs_mount+0x7f/0x810 fs/9p/vfs_super.c:124 cap_capable+0x23f/0x280 security/commoncap.c:77 legacy_get_tree+0xea/0x180 fs/fs_context.c:622 xfs_fs_commit_blocks+0x630/0x630 vfs_get_tree+0x88/0x270 fs/super.c:1547 do_new_mount fs/namespace.c:2816 [inline] do_mount+0x17ec/0x2900 fs/namespace.c:3141 _copy_from_user+0x116/0x170 lib/usercopy.c:16 __do_sys_mount fs/namespace.c:3350 [inline] __se_sys_mount+0xd3/0x100 fs/namespace.c:3327 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.2:15253 blocked for more than 144 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28528 15253 7204 0x00004004 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4222 __mutex_lock_common+0x129f/0x2fc0 kernel/locking/mutex.c:1033 ep_free+0xb7/0x240 fs/eventpoll.c:824 ep_eventpoll_poll+0x150/0x150 fs/eventpoll.c:938 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1118 ep_free+0xb7/0x240 fs/eventpoll.c:824 ep_eventpoll_poll+0x150/0x150 fs/eventpoll.c:938 ep_eventpoll_release+0x44/0x50 fs/eventpoll.c:864 __fput+0x2ed/0x750 fs/file_table.c:280 task_work_run+0x147/0x1d0 kernel/task_work.c:123 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:165 [inline] prepare_exit_to_usermode+0x48e/0x600 arch/x86/entry/common.c:196 syscall_return_slowpath+0xf9/0x420 arch/x86/entry/common.c:278 entry_SYSCALL_64_after_hwframe+0x49/0xb3 __phys_addr+0xb/0x120 arch/x86/mm/physaddr.c:16 schedule_timeout+0x3e/0x250 kernel/time/timer.c:1874 INFO: task syz-executor.2:15254 blocked for more than 144 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28496 15254 7204 0x00004004 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_timeout+0x43/0x250 kernel/time/timer.c:1874 mark_held_locks kernel/locking/lockdep.c:3628 [inline] __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x4a4/0x8a0 kernel/locking/lockdep.c:3702 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x1f/0x80 kernel/locking/spinlock.c:199 do_wait_for_common+0x232/0x370 kernel/sched/completion.c:85 console_conditional_schedule+0x30/0x30 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x43/0x50 kernel/sched/completion.c:138 __synchronize_srcu+0x1ba/0x240 kernel/rcu/srcutree.c:922 rcu_read_lock_any_held+0x1a0/0x1a0 arch/x86/include/asm/paravirt.h:754 wakeup_source_remove drivers/base/power/wakeup.c:202 [inline] wakeup_source_unregister+0x107/0x180 drivers/base/power/wakeup.c:246 ep_remove+0x422/0x500 fs/eventpoll.c:792 ep_eventpoll_poll+0x150/0x150 fs/eventpoll.c:938 ep_free+0x14b/0x240 fs/eventpoll.c:847 ep_eventpoll_poll+0x150/0x150 fs/eventpoll.c:938 ep_eventpoll_release+0x44/0x50 fs/eventpoll.c:864 __fput+0x2ed/0x750 fs/file_table.c:280 task_work_run+0x147/0x1d0 kernel/task_work.c:123 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:165 [inline] prepare_exit_to_usermode+0x48e/0x600 arch/x86/entry/common.c:196 syscall_return_slowpath+0xf9/0x420 arch/x86/entry/common.c:278 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.3:15262 blocked for more than 144 seconds. Not tainted 5.7.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28528 15262 7426 0x00004004 Call Trace: context_switch kernel/sched/core.c:3372 [inline] __schedule+0x805/0xc90 kernel/sched/core.c:4088 schedule+0x188/0x220 kernel/sched/core.c:4163 schedule_timeout+0x43/0x250 kernel/time/timer.c:1874 mark_held_locks kernel/locking/lockdep.c:3628 [inline] __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x4a4/0x8a0 kernel/locking/lockdep.c:3702 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x1f/0x80 kernel/locking/spinlock.c:199 do_wait_for_common+0x232/0x370 kernel/sched/completion.c:85 console_conditional_schedule+0x30/0x30 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x43/0x50 kernel/sched/completion.c:138 __synchronize_srcu+0x1ba/0x240 kernel/rcu/srcutree.c:922 rcu_read_lock_any_held+0x1a0/0x1a0 arch/x86/include/asm/paravirt.h:754 tracepoint_synchronize_unregister include/linux/tracepoint.h:82 [inline] perf_trace_event_unreg+0xbd/0x1d0 kernel/trace/trace_event_perf.c:168 perf_trace_destroy+0x93/0xb0 kernel/trace/trace_event_perf.c:243 perf_swevent_read+0x10/0x10 kernel/events/core.c:9005 _free_event+0x8ca/0xeb0 kernel/events/core.c:4792 put_event kernel/events/core.c:4886 [inline] perf_event_release_kernel+0xb8c/0xc50 kernel/events/core.c:5001 perf_mmap+0x1750/0x1750 include/linux/atomic-fallback.h:1089 perf_release+0x37/0x40 kernel/events/core.c:5011 __fput+0x2ed/0x750 fs/file_table.c:280 task_work_run+0x147/0x1d0 kernel/task_work.c:123 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:165 [inline] prepare_exit_to_usermode+0x48e/0x600 arch/x86/entry/common.c:196 syscall_return_slowpath+0xf9/0x420 arch/x86/entry/common.c:278 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Showing all locks held in the system: 2 locks held by kworker/u4:2/38: #0: ffff8880aa434138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: spin_unlock_irq include/linux/spinlock.h:403 [inline] #0: ffff8880aa434138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x6df/0xfd0 kernel/workqueue.c:2241 #1: ffffc90000eb7d80 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x71e/0xfd0 kernel/workqueue.c:2243 1 lock held by khungtaskd/1138: #0: ffffffff892e8590 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 net/mptcp/pm_netlink.c:858 3 locks held by kworker/1:3/2705: 1 lock held by in:imklog/6676: #0: ffff8880a36a35f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x25d/0x2f0 fs/file.c:826 2 locks held by agetty/6682: #0: ffff88809456f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900010f42e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x260/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by kworker/u4:15/2519: #0: ffff8880aa434138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: spin_unlock_irq include/linux/spinlock.h:403 [inline] #0: ffff8880aa434138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x6df/0xfd0 kernel/workqueue.c:2241 #1: ffffc90006bdfd80 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x71e/0xfd0 kernel/workqueue.c:2243 1 lock held by systemd-udevd/14846: #0: ffffffff89326638 (epmutex){+.+.}-{3:3}, at: eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 1 lock held by systemd-udevd/14848: #0: ffffffff89326638 (epmutex){+.+.}-{3:3}, at: eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 1 lock held by systemd-udevd/14878: #0: ffffffff89326638 (epmutex){+.+.}-{3:3}, at: eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 1 lock held by systemd-udevd/14938: #0: ffffffff89326638 (epmutex){+.+.}-{3:3}, at: eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 1 lock held by syz-executor.2/15253: #0: ffffffff89326638 (epmutex){+.+.}-{3:3}, at: ep_free+0xb7/0x240 fs/eventpoll.c:824 2 locks held by syz-executor.2/15254: #0: ffffffff89326638 (epmutex){+.+.}-{3:3}, at: ep_free+0xb7/0x240 fs/eventpoll.c:824 #1: ffff888094f85468 (&ep->mtx){+.+.}-{3:3}, at: ep_free+0x128/0x240 fs/eventpoll.c:844 1 lock held by syz-executor.3/15262: #0: ffffffff892fc5d8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x27/0xb0 kernel/trace/trace_event_perf.c:241 1 lock held by systemd-udevd/15269: #0: ffffffff89326638 (epmutex){+.+.}-{3:3}, at: eventpoll_release_file+0x29/0xe0 fs/eventpoll.c:998 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1138 Comm: khungtaskd Not tainted 5.7.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1e9/0x30e lib/dump_stack.c:118 nmi_cpu_backtrace+0x9f/0x180 lib/nmi_backtrace.c:101 arch_trigger_cpumask_backtrace+0x10/0x10 arch/x86/kernel/apic/hw_nmi.c:38 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xd2a/0xd40 kernel/hung_task.c:289 kthread+0x353/0x380 kernel/kthread.c:268 hungtask_pm_notify+0x50/0x50 kernel/hung_task.c:265 kthread_blkcg+0xd0/0xd0 kernel/kthread.c:1247 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2507 Comm: kworker/u4:12 Not tainted 5.7.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:write_comp_data kernel/kcov.c:207 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x90 kernel/kcov.c:274 Code: c1 e0 03 48 83 c8 18 49 89 14 02 4d 89 44 f2 18 49 ff c1 4d 89 0a c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 4c 8b 04 24 <65> 48 8b 04 25 40 1e 02 00 65 8b 0d c8 b7 8e 7e f7 c1 00 01 1f 00 RSP: 0018:ffffc90007fa7c20 EFLAGS: 00000246 RAX: ffffffff839ca226 RBX: 0000000000000001 RCX: ffff888015dda380 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000080000001 R08: ffffffff839ca243 R09: fffffbfff1628e9f R10: fffffbfff1628e9f R11: 0000000000000000 R12: ffff888052730c00 R13: dffffc0000000000 R14: ffffffff89024167 R15: ffffffff88e81cac FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7e8cf89000 CR3: 0000000092d2b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_preemption_disabled+0x33/0x240 lib/smp_processor_id.c:16 debug_smp_processor_id+0x5/0x20 lib/smp_processor_id.c:56 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:300 [inline] rcu_is_watching+0x1c/0xa0 kernel/rcu/tree.c:929 rcu_read_lock include/linux/rcupdate.h:602 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x105/0x5e0 net/batman-adv/network-coding.c:718 lock_is_held include/linux/lockdep.h:406 [inline] rcu_read_lock_sched_held+0x106/0x170 kernel/rcu/update.c:121 process_one_work+0x76e/0xfd0 kernel/workqueue.c:2268 worker_thread+0xa7f/0x1450 kernel/workqueue.c:2414 kthread+0x353/0x380 kernel/kthread.c:268 rcu_lock_release+0x20/0x20 include/linux/rcupdate.h:213 kthread_blkcg+0xd0/0xd0 kernel/kthread.c:1247 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352