INFO: task kworker/u8:16:5971 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:16 state:D stack:23544 pid:5971 tgid:5971 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc69/0x1ca0 kernel/locking/mutex.c:776
rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1703
rdma_dev_exit_net+0x2dd/0x590 drivers/infiniband/core/device.c:1181
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252
cleanup_net+0x41b/0x830 net/core/net_namespace.c:696
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task syz.5.2950:16236 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2950 state:D stack:24456 pid:16236 tgid:16235 ppid:15897 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/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:1318 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592
___sys_sendmsg+0x134/0x1d0 net/socket.c:2646
__sys_sendmsg+0x16d/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f28ba98f749
RSP: 002b:00007f28bb907038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f28babe5fa0 RCX: 00007f28ba98f749
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000004
RBP: 00007f28baa13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f28babe6038 R14: 00007f28babe5fa0 R15: 00007ffedc2c0458
INFO: task syz.3.2969:16320 blocked for more than 145 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.2969 state:D stack:26184 pid:16320 tgid:16312 ppid:5809 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc69/0x1ca0 kernel/locking/mutex.c:776
rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1703
rdma_dev_exit_net+0x2dd/0x590 drivers/infiniband/core/device.c:1181
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252
setup_net+0x1ff/0x3a0 net/core/net_namespace.c:462
copy_net_ns+0x351/0x7c0 net/core/net_namespace.c:581
create_new_namespaces+0x3ea/0xab0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:226
ksys_unshare+0x45b/0xa40 kernel/fork.c:3171
__do_sys_unshare kernel/fork.c:3242 [inline]
__se_sys_unshare kernel/fork.c:3240 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3240
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f67c6d8f749
RSP: 002b:00007f67c7c3d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f67c6fe6270 RCX: 00007f67c6d8f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042000000
RBP: 00007f67c6e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f67c6fe6308 R14: 00007f67c6fe6270 R15: 00007ffc2d962858
Showing all locks held in the system:
4 locks held by kworker/1:0/24:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c96a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c96a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c96a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:3/50:
#0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
#1: ffff8880b8524608 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8524608 (psi_seq){-.-.}-{0:0}, at: __schedule+0x19b1/0x6150 kernel/sched/core.c:6857
#2: ffff8880b8434778 (krc.lock){..-.}-{2:2}, at: kvfree_rcu_bulk+0xd3/0x1e0 mm/slab_common.c:1535
3 locks held by kworker/u8:14/4529:
#0: ffff88813ff69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000eed7c90 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:303
2 locks held by getty/5576:
#0: ffff88803735d0a0 (&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/0x1510 drivers/tty/n_tty.c:2211
4 locks held by kworker/u8:16/5971:
#0: ffff88801badc948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc900048ffc90 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff9012b3d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x830 net/core/net_namespace.c:670
#3: ffff888079980700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1703
2 locks held by syz.5.2950/16236:
#0: ffffffff9af7abd8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg+0x169/0x6e0 drivers/infiniband/core/netlink.c:164
#1: ffff888079980700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x23b/0x480 drivers/infiniband/core/device.c:1551
2 locks held by syz.3.2969/16320:
#0: ffffffff9012b3d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
#1: ffff888079980700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1703
1 lock held by syz-executor/16443:
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
1 lock held by syz-executor/16555:
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
1 lock held by syz.4.3427/18075:
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
9 locks held by syz-executor/18367:
#0: ffff888032ff6420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#1: ffff888021be7888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x570 fs/kernfs/file.c:343
#2: ffff88814273fb48 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88814273fb48 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2ff/0x570 fs/kernfs/file.c:344
#3: ffffffff8f6b7808 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234
#4: ffff8881432b70e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#4: ffff8881432b70e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1104 [inline]
#4: ffff8881432b70e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1302
#5: ffff88803afea250 (&devlink->lock_key#15){+.+.}-{4:4}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1777
#6: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x108/0x830 drivers/net/netdevsim/netdev.c:1175
#7: ffff88807a7a8d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2781 [inline]
#7: ffff88807a7a8d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x1a23/0x2590 net/core/dev.c:12341
#8: ffffffff8e3d4df8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz.1.3505/18376:
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90141ba8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x133/0x180 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xe66/0x1180 kernel/hung_task.c:515
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: c6 5f 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 49 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197de8 EFLAGS: 000002c6
RAX: 00000000041ad0a7 RBX: 0000000000000001 RCX: ffffffff8b7816d9
RDX: 0000000000000000 RSI: ffffffff8dacdf23 RDI: ffffffff8bf2b400
RBP: ffffed1003b56498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dab2ff0 R12: 0000000000000001
R13: ffff88801dab24c0 R14: ffffffff9088b4d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881249f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb6e19f6990 CR3: 000000000e184000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148