INFO: task syz.0.17:4514 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:26688 pid:4514 ppid:4380 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747
comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
chrdev_open+0x597/0x670 fs/char_dev.c:414
do_dentry_open+0x7e9/0x10d0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x25c6/0x2e70 fs/namei.c:3791
do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
do_sys_openat2+0x142/0x490 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb93478f749
RSP: 002b:00007ffd35eceec8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb9349e5fa0 RCX: 00007fb93478f749
RDX: 0000000000000400 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fb934813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb9349e5fa0 R14: 00007fb9349e5fa0 R15: 0000000000000004
INFO: task syz.1.18:4517 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18 state:D stack:26688 pid:4517 ppid:4384 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747
comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
chrdev_open+0x597/0x670 fs/char_dev.c:414
do_dentry_open+0x7e9/0x10d0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x25c6/0x2e70 fs/namei.c:3791
do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
do_sys_openat2+0x142/0x490 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa7ed58f749
RSP: 002b:00007ffc359dd968 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa7ed7e5fa0 RCX: 00007fa7ed58f749
RDX: 0000000000000400 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fa7ed613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa7ed7e5fa0 R14: 00007fa7ed7e5fa0 R15: 0000000000000004
INFO: task syz.4.21:4518 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21 state:D stack:26688 pid:4518 ppid:4391 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747
comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
chrdev_open+0x597/0x670 fs/char_dev.c:414
do_dentry_open+0x7e9/0x10d0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x25c6/0x2e70 fs/namei.c:3791
do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
do_sys_openat2+0x142/0x490 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f980538f749
RSP: 002b:00007ffda1558e98 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f98055e5fa0 RCX: 00007f980538f749
RDX: 0000000000000400 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007f9805413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f98055e5fa0 R14: 00007f98055e5fa0 R15: 0000000000000004
Showing all locks held in the system:
2 locks held by kworker/u4:1/11:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8c92bab0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8c92c2d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
3 locks held by kworker/0:1/14:
#0: ffff88814d53f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90000137d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x14d0 net/ipv6/addrconf.c:4131
1 lock held by khungtaskd/28:
#0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by kworker/u4:2/32:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90000a8fd00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
2 locks held by getty/4025:
#0: ffff88802fc3f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
3 locks held by kworker/u4:7/4452:
2 locks held by kworker/1:11/4464:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90003787d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
2 locks held by syz.3.20/4512:
1 lock held by syz.0.17/4514:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.1.18/4517:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.4.21/4518:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.2.19/4520:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.5.22/4653:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.7.24/4654:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.6.23/4655:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.8.25/4656:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.9.26/4657:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.3.27/4720:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.0.28/4747:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.1.29/4753:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.2.31/4759:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.4.30/4763:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.5.32/4810:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.7.33/4853:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.6.34/4906:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.8.36/4907:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.9.35/4908:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.3.37/4931:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz.0.38/4941:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
1 lock held by syz-executor/4952:
#0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147
1 lock held by syz-executor/4953:
#0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147
7 locks held by syz-executor/4976:
#0: ffff88807e84e460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580
#1: ffff888049809488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343
#2: ffff888026e9d008 (kn->active#59){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888026e9d008 (kn->active#59){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x236/0x520 fs/kernfs/file.c:344
#3: ffffffff8d44d168 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xce/0x360 drivers/net/netdevsim/bus.c:209
#4: ffff88805d5130e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#4: ffff88805d5130e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline]
#4: ffff88805d5130e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb2/0x850 drivers/base/dd.c:1283
#5: ffff88805d5172f8 (&devlink->lock_key#17){+.+.}-{3:3}, at: nsim_drv_remove+0x54/0x160 drivers/net/netdevsim/dev.c:1677
#6: ffffffff8c930cc0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4023
2 locks held by syz-executor/5000:
#0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147
#1: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#1: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
1 lock held by syz.1.39/5019:
#0: ffff88814d0970f8 (&dev->mutex#3){+.+.}-{3:3}, at: comedi_open+0xbc/0x580 drivers/comedi/comedi_fops.c:2811
3 locks held by kworker/u4:10/5023:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000576fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
2 locks held by dhcpcd/5029:
#0: ffff8880478de130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
#0: ffff8880478de130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
#1: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#1: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4339 Comm: kworker/0:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events nsim_fib_event_work
RIP: 0010:trace_hardirqs_off+0xe/0x40 kernel/trace/trace_preemptirq.c:78
Code: 80 c1 03 38 c1 0f 8c 6a ff ff ff 48 c7 c7 30 10 ff 8d e8 35 d2 49 00 e9 59 ff ff ff 53 48 8b 5c 24 08 48 89 df e8 02 2f 89 08 <65> 8b 05 43 f7 7b 7e 85 c0 75 19 65 c7 05 34 f7 7b 7e 01 00 00 00
RSP: 0018:ffffc90003da7678 EFLAGS: 00000086
RAX: fcaaa749b8a56000 RBX: ffffffff81d09687 RCX: fcaaa749b8a56000
RDX: 0000000000000001 RSI: ffffffff8a6c0600 RDI: ffffffff8abef920
RBP: 0000000000000286 R08: ffff888052858000 R09: 0000000080040003
R10: fffffbfff2119067 R11: 1ffffffff2119066 R12: ffff888017442140
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffea00014a1600
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555caa95c8 CR3: 000000007a524000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
put_cpu_partial+0x47/0x250 mm/slub.c:2639
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
__kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398
kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026
kmalloc include/linux/slab.h:563 [inline]
kzalloc include/linux/slab.h:699 [inline]
nsim_fib6_rt_create drivers/net/netdevsim/fib.c:547 [inline]
nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:752 [inline]
nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline]
nsim_fib_event drivers/net/netdevsim/fib.c:889 [inline]
nsim_fib_event_work+0x10f2/0x32b0 drivers/net/netdevsim/fib.c:1494
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
process_scheduled_works kernel/workqueue.c:2355 [inline]
worker_thread+0xd62/0x1250 kernel/workqueue.c:2441
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295