INFO: task syz-executor.3:10553 can't die for more than 143 seconds.
task:syz-executor.3  state:D stack:25944 pid:10553 ppid:  8448 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4329 [inline]
 __schedule+0x911/0x2160 kernel/sched/core.c:5079
 schedule+0xcf/0x270 kernel/sched/core.c:5158
 schedule_timeout+0x14a/0x250 kernel/time/timer.c:1878
 schedule_timeout_uninterruptible kernel/time/timer.c:1912 [inline]
 msleep+0xa4/0xf0 kernel/time/timer.c:2032
 netdev_wait_allrefs net/core/dev.c:10457 [inline]
 netdev_run_todo+0x9e8/0xe10 net/core/dev.c:10538
 register_netdev+0x35/0x50 net/core/dev.c:10381
 sit_init_net+0x3a4/0xac0 net/ipv6/sit.c:1917
 ops_init+0xaf/0x470 net/core/net_namespace.c:140
 setup_net+0x40f/0xa30 net/core/net_namespace.c:333
 copy_net_ns+0x31e/0x760 net/core/net_namespace.c:474
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x8e0 kernel/fork.c:2994
 __do_sys_unshare kernel/fork.c:3062 [inline]
 __se_sys_unshare kernel/fork.c:3060 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3060
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x466459
RSP: 002b:00007f6a265e7188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000060000000
RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fff1eade13f R14: 00007f6a265e7300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1644:
 #0: ffffffff8bf75360 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333
1 lock held by in:imklog/8135:
1 lock held by syz-executor.3/10553:
 #0: ffffffff8d674910 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470

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