INFO: task syz.3.398:7422 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.398 state:D stack:23328 pid:7422 tgid:7420 ppid:5825 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
disable_device+0x1c6/0x320 drivers/infiniband/core/device.c:1325
__ib_unregister_device+0x2cb/0x3f0 drivers/infiniband/core/device.c:1555
ib_unregister_device_and_put+0xb8/0xf0 drivers/infiniband/core/device.c:1620
nldev_dellink+0x2d1/0x320 drivers/infiniband/core/nldev.c:1827
rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
rdma_nl_rcv+0x6ae/0x980 drivers/infiniband/core/netlink.c:259
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
____sys_sendmsg+0x505/0x820 net/socket.c:2592
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2681
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d1658f749
RSP: 002b:00007f1d1749f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1d167e5fa0 RCX: 00007f1d1658f749
RDX: 0000000000008000 RSI: 0000200000000600 RDI: 0000000000000004
RBP: 00007f1d16613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d167e6038 R14: 00007f1d167e5fa0 R15: 00007fff3bb602d8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:9/1116:
#0: ffff88801aa9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801aa9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90003c0fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90003c0fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8f304cd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670
#3: ffff8880793fc700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1703
2 locks held by getty/5586:
#0: ffff88814e0f00a0 (&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+0x449/0x1460 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5826:
3 locks held by kworker/0:7/5976:
#0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639
#1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
#2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085
3 locks held by kworker/0:9/5990:
#0: ffff88813ff15948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff15948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000b987bc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000b987bc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:956
2 locks held by syz.3.398/7422:
#0: ffffffff99c80df8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:164 [inline]
#0: ffffffff99c80df8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
#0: ffffffff99c80df8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980 drivers/infiniband/core/netlink.c:259
#1: ffff8880793fc700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0 drivers/infiniband/core/device.c:1551
1 lock held by syz-executor/8240:
#0: ffffffff8f311d88 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f311d88 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: bat_events batadv_mcast_mla_update
RIP: 0010:lock_acquire+0xb/0x340 kernel/locking/lockdep.c:5828
Code: 95 c0 c3 cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 <41> 54 53 48 83 ec 60 4d 89 ce 45 89 c7 41 89 cc 89 54 24 04 89 f3
RSP: 0018:ffffc90000117750 EFLAGS: 00000046
RAX: 1ffff1100385de14 RBX: 0000000000000296 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff99b38da8
RBP: 0000000000212008 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: ffff88809535cce0
R13: ffff88809535ccc0 R14: ffffffff99b38d90 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125e21000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d5dbb40f40 CR3: 000000000dd3a000 CR4: 00000000003526f0
Call Trace:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
__debug_check_no_obj_freed lib/debugobjects.c:1088 [inline]
debug_check_no_obj_freed+0x145/0x550 lib/debugobjects.c:1129
slab_free_hook mm/slub.c:2471 [inline]
slab_free mm/slub.c:6670 [inline]
kfree+0x13b/0x660 mm/slub.c:6878
batadv_mcast_mla_list_free net/batman-adv/multicast.c:667 [inline]
__batadv_mcast_mla_update net/batman-adv/multicast.c:924 [inline]
batadv_mcast_mla_update+0x3293/0x3640 net/batman-adv/multicast.c:946
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
IPVS: sh: UDP 224.0.0.2:0 - no destination available