INFO: task syz.3.392:6359 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.392 state:D stack:27360 pid:6359 ppid:4264 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
d_wait_lookup fs/dcache.c:2634 [inline]
d_alloc_parallel+0xb95/0x1530 fs/dcache.c:2716
__lookup_slow+0x113/0x3a0 fs/namei.c:1683
lookup_slow+0x53/0x70 fs/namei.c:1715
walk_component fs/namei.c:2006 [inline]
link_path_walk+0x928/0xe50 fs/namei.c:2333
path_lookupat+0x9d/0x440 fs/namei.c:2486
do_o_path+0x94/0x1f0 fs/namei.c:3762
path_openat+0x2897/0x2e70 fs/namei.c:3784
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: 0033:0x7f04ed38f749
RSP: 002b:00007f04ee24c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f04ed5e6090 RCX: 00007f04ed38f749
RDX: 0000000000200002 RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007f04ed413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f04ed5e6128 R14: 00007f04ed5e6090 R15: 00007ffd0553c0d8
Showing all locks held in the system:
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
1 lock held by khungtaskd/27:
#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
3 locks held by kworker/u4:3/46:
4 locks held by udevd/3637:
#0: ffff888056fd3668 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
#1: ffff888029503888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x58/0x410 fs/kernfs/file.c:172
#2: ffff88806677de88 (kn->active#5){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88806677de88 (kn->active#5){.+.+}-{0:0}, at: kernfs_seq_start+0xae/0x410 fs/kernfs/file.c:173
#3: ffff88807b2400e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#3: ffff88807b2400e8 (&dev->mutex){....}-{3:3}, at: uevent_show+0x16c/0x320 drivers/base/core.c:2669
1 lock held by dhcpcd/3932:
#0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x288/0x1af0 net/ipv4/devinet.c:1080
2 locks held by getty/4026:
#0: ffff888030166098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
3 locks held by kworker/u4:8/4362:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004aa7d00 ((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
5 locks held by kworker/u4:9/4408:
#0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004cffd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db2e6d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:594
#3: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe5/0xa50 net/core/dev.c:11489
#4: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#4: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
3 locks held by kworker/0:9/4451:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004cefd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104
5 locks held by kworker/u4:13/4983:
3 locks held by kworker/1:17/5064:
#0: ffff88814d2f2d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000cd3fd00 ((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 syz.3.392/6354:
1 lock held by syz.3.392/6359:
#0: ffff8880719611a0 (&type->i_mutex_dir_key#20){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
#0: ffff8880719611a0 (&type->i_mutex_dir_key#20){.+.+}-{3:3}, at: lookup_slow+0x46/0x70 fs/namei.c:1714
2 locks held by kworker/0:17/6566:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000f1afd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
1 lock held by syz-executor/7467:
#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
4 locks held by syz-executor/7469:
#0: ffff88807f09e460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580
#1: ffff8880525abc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343
#2: ffff888144769bd0 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888144769bd0 (kn->active#53){.+.+}-{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
7 locks held by syz-executor/7470:
#0: ffff88807f09e460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580
#1: ffff88804b6b6c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343
#2: ffff888144769ae8 (kn->active#54){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888144769ae8 (kn->active#54){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x236/0x520 fs/kernfs/file.c:344
#3: ffffffff8d44d168 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x129/0x670 drivers/net/netdevsim/bus.c:160
#4: ffff88807b2400e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#4: ffff88807b2400e8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x460 drivers/base/dd.c:990
#5:
ffff88807b2412f8 (&devlink->lock_key#8){+.+.}-{3:3}, at: nsim_drv_probe+0xc0/0xaf0 drivers/net/netdevsim/dev.c:1542
#6: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:310 [inline]
#6: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_create+0x31d/0x410 drivers/net/netdevsim/netdev.c:365
1 lock held by syz-executor/7473:
#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/7476:
#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
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4669 Comm: kworker/1:15 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_long defense_work_handler
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:104 [inline]
RIP: 0010:do_raw_spin_unlock+0xc3/0x230 kernel/locking/spinlock_debug.c:140
Code: 48 c1 ed 03 42 0f b6 44 25 00 84 c0 0f 85 3d 01 00 00 41 8b 07 65 8b 0d db cf 9d 7e 39 c8 0f 85 cf 00 00 00 43 80 7c 25 00 00 <74> 08 4c 89 f7 e8 c3 c7 6c 00 49 c7 06 ff ff ff ff 42 0f b6 44 25
RSP: 0018:ffffc90005527968 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffffffff96bff728 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff96bff728
RBP: 1ffffffff2d7fee6 R08: dffffc0000000000 R09: fffffbfff2d7fee6
R10: fffffbfff2d7fee6 R11: 1ffffffff2d7fee5 R12: dffffc0000000000
R13: 1ffffffff2d7fee7 R14: ffffffff96bff738 R15: ffffffff96bff730
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005576bcd2c000 CR3: 0000000030ed4000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline]
_raw_spin_unlock_irqrestore+0x75/0x100 kernel/locking/spinlock.c:194
debug_object_assert_init+0x1ed/0x2f0 lib/debugobjects.c:889
debug_timer_assert_init kernel/time/timer.c:792 [inline]
debug_assert_init kernel/time/timer.c:837 [inline]
__mod_timer+0x54/0xd00 kernel/time/timer.c:1020
queue_delayed_work_on+0x126/0x1e0 kernel/workqueue.c:1704
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295