INFO: task syz.4.5912:18872 blocked for more than 144 seconds.
      Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.5912      state:D
 stack:25808 pid:18872 tgid:18871 ppid:6022   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6764
 __schedule_loop kernel/sched/core.c:6841 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6856
 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
 disable_device+0x170/0x280 drivers/infiniband/core/device.c:1279
 __ib_unregister_device+0x2b4/0x480 drivers/infiniband/core/device.c:1502
 ib_unregister_device_and_put+0x5a/0x80 drivers/infiniband/core/device.c:1567
 nldev_dellink+0x211/0x300 drivers/infiniband/core/nldev.c:1825
 rdma_nl_rcv_msg+0x388/0x6e0 drivers/infiniband/core/netlink.c:195
 rdma_nl_rcv_skb.constprop.0.isra.0+0x2e6/0x450 drivers/infiniband/core/netlink.c:239
 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]
 netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1348
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1892
 sock_sendmsg_nosec net/socket.c:713 [inline]
 __sock_sendmsg net/socket.c:728 [inline]
 ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2568
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2622
 __sys_sendmsg+0x16e/0x220 net/socket.c:2654
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff40738cda9
RSP: 002b:00007ff4081d5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff4075a5fa0 RCX: 00007ff40738cda9
RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 0000000000000003
RBP: 00007ff40740e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff4075a5fa0 R15: 00007ffcd438fdd8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746
5 locks held by kworker/u8:4/65:
3 locks held by kworker/0:2/970:
4 locks held by kworker/u8:7/3911:
 #0: ffff88801beeb148 ((wq_completion)netns
){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211
 #1: ffffc9000e457d18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212
 #2: ffffffff8fededd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xca/0xbf0 net/core/net_namespace.c:606
 #3: ffff888032a746c0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1650
2 locks held by getty/5569:
 #0: ffff8880377520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
2 locks held by syz.4.5912/18872:
 #0: ffffffff9ac050f8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}
, at: rdma_nl_rcv_msg+0x16a/0x6e0 drivers/infiniband/core/netlink.c:164
 #1: ffff888032a746c0 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x23b/0x480 drivers/infiniband/core/device.c:1498
1 lock held by syz-executor/19702:
 #0: ffffffff8e1c80f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:302
2 locks held by syz.3.8451/26090:
4 locks held by syz.2.8466/26168:
1 lock held by syz.1.8469/26179:
 #0: ffffffff8e1c80f8
 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:334

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc1-syzkaller-00020-g0de63bb7d919 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
 watchdog+0xf62/0x12b0 kernel/hung_task.c:399
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored