INFO: task syz.0.785:9256 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.785 state:D stack:23840 pid:9256 tgid:9254 ppid:5835 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591 rdma_dev_exit_net+0x8c/0x340 drivers/infiniband/core/device.c:1159 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x49a/0x990 net/core/net_namespace.c:252 setup_net+0x2d6/0x320 net/core/net_namespace.c:461 copy_net_ns+0x34e/0x4e0 net/core/net_namespace.c:580 create_new_namespaces+0x3f3/0x720 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:218 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc978f8eec9 RSP: 002b:00007fc979da1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fc9791e6090 RCX: 00007fc978f8eec9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062040200 RBP: 00007fc979011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc9791e6128 R14: 00007fc9791e6090 R15: 00007fff0caf3568 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8dd3a860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8dd3a860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8dd3a860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:2/36: #0: ffff88801aef6948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801aef6948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90000ac7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90000ac7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:669 #3: ffffffff8ee199d0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x8c/0x340 drivers/infiniband/core/device.c:1159 2 locks held by getty/5598: #0: ffff88814ddf50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by ipvs-e:2:0/7510: #0: ffff8880b8839fd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:638 7 locks held by syz.1.766/9188: 2 locks held by syz.0.785/9256: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8ee199d0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x8c/0x340 drivers/infiniband/core/device.c:1159 2 locks held by syz-executor/9309: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8ee199d0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x8c/0x340 drivers/infiniband/core/device.c:1159 2 locks held by syz-executor/9317: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8ee199d0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x8c/0x340 drivers/infiniband/core/device.c:1159 2 locks held by syz.4.805/9336: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8ee199d0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x8c/0x340 drivers/infiniband/core/device.c:1159 3 locks held by syz-executor/9351: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8ee19810 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x19a/0x270 drivers/infiniband/core/device.c:1215 #2: ffff88801aef7988 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_add_one+0x41/0x520 fs/kernfs/dir.c:791 2 locks held by syz-executor/9354: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8f0c4a88 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160 2 locks held by syz.3.812/9361: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8f0c4a88 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160 2 locks held by syz-executor/9366: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576 #1: ffffffff8f0c4a88 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160 2 locks held by syz-executor/9368: #0: ffffffff8f0b7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576