INFO: task syz-executor.3:20656 can't die for more than 143 seconds.
task:syz-executor.3  state:R  running task     stack:25288 pid:20656 ppid:  8520 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4325 [inline]
 __schedule+0x8eb/0x21b0 kernel/sched/core.c:5076
 synchronize_net+0x29/0x50 net/core/dev.c:10632

Showing all locks held in the system:
1 lock held by khungtaskd/1662:
 #0: ffffffff8b78db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x28c kernel/locking/lockdep.c:6254
1 lock held by in:imklog/8181:
 #0: ffff888011867270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:923
2 locks held by agetty/8415:
 #0: ffff888015465098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266
 #1: ffffc90000f882e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x21d/0x1ac0 drivers/tty/n_tty.c:2158
4 locks held by kworker/u4:11/15046:
 #0: ffff8880116ab138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8880116ab138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff8880116ab138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff8880116ab138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff8880116ab138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff8880116ab138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x1630 kernel/workqueue.c:2246
 #1: ffffc9000982fda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1630 kernel/workqueue.c:2250
 #2: ffffffff8d0bc590 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:566
 #3: ffffffff8b798070 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x44/0x420 kernel/rcu/tree.c:3899
2 locks held by syz-executor.3/20656:
 #0: ffffffff8d0bc590 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x352/0x7b0 net/core/net_namespace.c:479
 #1: ffffffff8b798168 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8b798168 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4ff/0x620 kernel/rcu/tree_exp.h:836
1 lock held by syz-executor.1/20696:

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