INFO: task syz.2.981:6327 blocked for more than 430 seconds.
      Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.981       state:D stack:0     pid:6327  tgid:6326  ppid:4132   flags:0x0000000d
Call trace:
 __switch_to+0x204/0x4bc arch/arm64/kernel/process.c:701 (T)
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0xafc/0x2eb8 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xd0/0x304 kernel/sched/core.c:6848
 schedule_timeout+0x1dc/0x214 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common+0x1d4/0x4b0 kernel/sched/completion.c:116
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x20/0x2c kernel/sched/completion.c:148
 disable_device+0x14c/0x228 drivers/infiniband/core/device.c:1296
 __ib_unregister_device+0x22c/0x3a8 drivers/infiniband/core/device.c:1519
 ib_unregister_device_and_put+0x50/0x78 drivers/infiniband/core/device.c:1584
 nldev_dellink+0x190/0x264 drivers/infiniband/core/nldev.c:1825
 rdma_nl_rcv_msg+0x274/0x56c drivers/infiniband/core/netlink.c:195
 rdma_nl_rcv_skb.constprop.0.isra.0+0x204/0x340 drivers/infiniband/core/netlink.c:239
 rdma_nl_rcv+0x10/0x1c drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x3c4/0x674 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0x654/0xa4c net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0xc8/0x168 net/socket.c:726
 ____sys_sendmsg+0x54c/0x6dc net/socket.c:2583
 ___sys_sendmsg+0x11c/0x19c net/socket.c:2637
 __sys_sendmsg+0x114/0x198 net/socket.c:2669
 __do_sys_sendmsg net/socket.c:2674 [inline]
 __se_sys_sendmsg net/socket.c:2672 [inline]
 __arm64_sys_sendmsg+0x70/0xa0 net/socket.c:2672
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x50/0x180 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x10c/0x138 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffff800086f896e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x44/0x2d0 kernel/locking/lockdep.c:6738
2 locks held by getty/3219:
 #0: ffff00001647e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80008d05b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x93c/0xe9c drivers/tty/n_tty.c:2211
1 lock held by syz-executor/3273:
2 locks held by syz.2.981/6327:
 #0: ffff80008cecf318 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg+0x130/0x56c drivers/infiniband/core/netlink.c:164
 #1: ffff000016c346b8 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x1c8/0x3a8 drivers/infiniband/core/device.c:1515
4 locks held by kworker/u8:9/6375:
 #0: ffff00000d962148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x6e0/0x189c kernel/workqueue.c:3204
 #1: ffff8000a0227ce0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x704/0x189c kernel/workqueue.c:3204
 #2: ffff80008832f4b0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xcc/0x928 net/core/net_namespace.c:602
 #3: ffff000016c346b8 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x38/0x21c drivers/infiniband/core/device.c:1667
2 locks held by kworker/u8:11/6559:
1 lock held by syz.0.1225/7135:

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