INFO: task syz.3.2165:14800 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.2165 state:D stack:24392 pid:14800 tgid:14799 ppid:5860 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2ff/0x4e0 kernel/sched/completion.c:121 disable_device+0x16f/0x280 drivers/infiniband/core/device.c:1325 __ib_unregister_device+0x2b4/0x480 drivers/infiniband/core/device.c:1555 ib_unregister_device_and_put+0x5a/0x80 drivers/infiniband/core/device.c:1620 nldev_dellink+0x21f/0x320 drivers/infiniband/core/nldev.c:1827 rdma_nl_rcv_msg+0x38a/0x6e0 drivers/infiniband/core/netlink.c:195 rdma_nl_rcv_skb.constprop.0.isra.0+0x2d0/0x430 drivers/infiniband/core/netlink.c:239 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f70b458eec9 RSP: 002b:00007f70b53da038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f70b47e5fa0 RCX: 00007f70b458eec9 RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000007 RBP: 00007f70b4611f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f70b47e6038 R14: 00007f70b47e5fa0 R15: 00007fff1fd021d8 Showing all locks held in the system: 1 lock held by rcu_tasks_trace/29: 1 lock held by khungtaskd/31: #0: ffffffff8e5c16a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c16a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c16a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:4/59: 4 locks held by kworker/u8:9/3018: #0: ffff88801c6f4148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000c887d10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff9036f310 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x890 net/core/net_namespace.c:658 #3: ffff888034bd8700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1703 2 locks held by getty/5614: #0: ffff88814d83a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 2 locks held by syz.3.2165/14800: #0: ffffffff9b1a4ad8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg+0x169/0x6e0 drivers/infiniband/core/netlink.c:164 #1: ffff888034bd8700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x23b/0x480 drivers/infiniband/core/device.c:1551 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: __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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6112 Comm: ipvs-e:5:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__pick_eevdf+0x3d4/0x670 kernel/sched/fair.c:956 Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 96 02 00 00 48 3b 5d 28 0f 88 f9 fe ff ff 49 89 ec e9 f1 fe ff ff 31 ed <4d> 85 ff 74 f1 48 b8 00 00 00 00 00 fc ff df 49 8d 7f 50 48 89 fa RSP: 0018:ffffc90003277950 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff88801e2e0090 RCX: 1ffff110170a7483 RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8880b853a418 RBP: ffff88801e2e0080 R08: 0000000000000000 R09: fffffbfff2156ed2 R10: ffffffff90ab7697 R11: 0000000000000001 R12: ffff88801e2e0090 R13: ffff8880b853a3c0 R14: 0000000000000001 R15: ffff8880272a4900 FS: 0000000000000000(0000) GS:ffff8881247b2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a2a59ecda8 CR3: 0000000074265000 CR4: 00000000003526f0 Call Trace: pick_eevdf kernel/sched/fair.c:1007 [inline] pick_next_entity kernel/sched/fair.c:5524 [inline] pick_task_fair+0xc1/0x330 kernel/sched/fair.c:8758 pick_task kernel/sched/core.c:6061 [inline] pick_next_task kernel/sched/core.c:6161 [inline] __schedule+0x2656/0x5de0 kernel/sched/core.c:6902 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 ip_vs_estimation_kthread+0x888/0x3310 net/netfilter/ipvs/ip_vs_est.c:209 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245