INFO: task syz-executor.0:11556 can't die for more than 143 seconds.
task:syz-executor.0  state:D stack:26088 pid:11556 ppid:  8504 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4325 [inline]
 __schedule+0x8cd/0x2150 kernel/sched/core.c:5076
 schedule+0xcf/0x270 kernel/sched/core.c:5155
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:5214
 __mutex_lock_common kernel/locking/mutex.c:1033 [inline]
 __mutex_lock+0x81a/0x1110 kernel/locking/mutex.c:1103
 ip_fib_net_exit+0x1b/0x2b0 net/ipv4/fib_frontend.c:1544
 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:187
 setup_net+0x508/0x850 net/core/net_namespace.c:365
 copy_net_ns+0x31e/0x760 net/core/net_namespace.c:483
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:231
 ksys_unshare+0x445/0x8e0 kernel/fork.c:2956
 __do_sys_unshare kernel/fork.c:3024 [inline]
 __se_sys_unshare kernel/fork.c:3022 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3022
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e0f9
RSP: 002b:00007fc6dd410c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000045e0f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 000000000119bfb0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007fffd2198d5f R14: 00007fc6dd4119c0 R15: 000000000119bf8c

Showing all locks held in the system:
5 locks held by kworker/u4:0/9:
 #0: ffff888010e5f138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010e5f138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888010e5f138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888010e5f138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888010e5f138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888010e5f138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2243
 #1: ffffc90000ce7da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2247
 #2: ffffffff8c92ed90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:566
 #3: ffffffff8c940f88 (rtnl_mutex){+.+.}-{3:3}, at: sit_exit_batch_net+0x88/0x700 net/ipv6/sit.c:1938
 #4: ffffffff8b342f68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #4: ffffffff8b342f68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x27e/0x610 kernel/rcu/tree_exp.h:836
1 lock held by khungtaskd/1661:
 #0: ffffffff8b33a7a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254
2 locks held by kworker/1:2/3084:
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2243
 #1: ffffc90002107da8 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2247
1 lock held by in:imklog/8185:
2 locks held by kworker/1:3/9344:
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2243
 #1: ffffc900037efda8 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2247
1 lock held by syz-executor.5/11540:
 #0: ffffffff8c940f88 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:676 [inline]
 #0: ffffffff8c940f88 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3354
2 locks held by syz-executor.0/11556:
 #0: ffffffff8c92ed90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:479
 #1: ffffffff8c940f88 (rtnl_mutex){+.+.}-{3:3}, at: ip_fib_net_exit+0x1b/0x2b0 net/ipv4/fib_frontend.c:1544
3 locks held by syz-executor.2/11559:
 #0: ffff888070d1cf40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x111/0x1110 net/bluetooth/hci_core.c:1720
 #1: ffff888070d1c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26f/0x1110 net/bluetooth/hci_core.c:1757
 #2: ffffffff8b342f68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #2: ffffffff8b342f68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f2/0x610 kernel/rcu/tree_exp.h:836
2 locks held by kworker/1:6/11682:
 #0: ffff88801007c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff88801007c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff88801007c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff88801007c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff88801007c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff88801007c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2243
 #1: ffffc90009c07da8 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2247

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