INFO: task syz-executor.0:17663 can't die for more than 143 seconds.
task:syz-executor.0  state:D stack:27064 pid:17663 ppid: 13971 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4984 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6265
 schedule+0xd2/0x260 kernel/sched/core.c:6338
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6397
 __mutex_lock_common kernel/locking/mutex.c:680 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740
 rcu_barrier+0x44/0x440 kernel/rcu/tree.c:3985
 setup_net+0x731/0xa30 net/core/net_namespace.c:355
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:470
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3126
 __do_sys_unshare kernel/fork.c:3197 [inline]
 __se_sys_unshare kernel/fork.c:3195 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3195
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f26d0ae3ae9
RSP: 002b:00007f26ce059188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f26d0bf6f60 RCX: 00007f26d0ae3ae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f26d0b3df25 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd87fa91df R14: 00007f26ce059300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.3:17665 can't die for more than 143 seconds.
task:syz-executor.3  state:D stack:27080 pid:17665 ppid:  6531 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4984 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6265
 schedule+0xd2/0x260 kernel/sched/core.c:6338
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6397
 __mutex_lock_common kernel/locking/mutex.c:680 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740
 rcu_barrier+0x44/0x440 kernel/rcu/tree.c:3985
 setup_net+0x731/0xa30 net/core/net_namespace.c:355
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:470
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3126
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f439946aae9
RSP: 002b:00007f43969e0188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: fffffffffffffffc RBX: 00007f439957df60 RCX: 00007f439946aae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f43994c4f25 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc5494cdbf R14: 00007f43969e0300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb83a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
3 locks held by kworker/u4:2/45:
1 lock held by in:imklog/6221:
3 locks held by syz-executor.0/17663:

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