INFO: task syz.5.1158:15318 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1158 state:D stack:25240 pid:15318 tgid:15317 ppid:9645 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
percpu_rwsem_wait+0x2e6/0x330 kernel/locking/percpu-rwsem.c:164
__percpu_down_read+0xfc/0x140 kernel/locking/percpu-rwsem.c:180
percpu_down_read_internal include/linux/percpu-rwsem.h:67 [inline]
percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
__sb_start_write include/linux/fs/super.h:19 [inline]
sb_start_write+0x18e/0x1c0 include/linux/fs/super.h:125
mnt_want_write+0x41/0x90 fs/namespace.c:499
filename_create+0x14f/0x360 fs/namei.c:4872
do_mkdirat+0xca/0x4b0 fs/namei.c:5156
__do_sys_mkdirat fs/namei.c:5186 [inline]
__se_sys_mkdirat fs/namei.c:5184 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5184
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: 0033:0x7f1fd179f749
RSP: 002b:00007f1fcf9fe038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f1fd19f5fa0 RCX: 00007f1fd179f749
RDX: 0000000000000000 RSI: 0000200000000440 RDI: ffffffffffffff9c
RBP: 00007f1fd1823f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1fd19f6038 R14: 00007f1fd19f5fa0 R15: 00007ffc2e4f2158
Showing all locks held in the system:
4 locks held by pr/legacy/17:
1 lock held by kauditd/37:
#0: ffffffff8d5fd418 (kauditd_wait.lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#0: ffffffff8d5fd418 (kauditd_wait.lock){+.+.}-{3:3}, at: finish_wait+0xbf/0x1f0 kernel/sched/wait.c:394
1 lock held by khungtaskd/38:
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
6 locks held by kworker/u8:5/82:
5 locks held by kworker/u8:12/2197:
2 locks held by getty/5557:
#0: ffff88803585d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211
3 locks held by kworker/u8:17/10343:
#0: ffff88814cf06938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88814cf06938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000c8bfbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000c8bfbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e8a5938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8e8a5938 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
1 lock held by syz.5.1158/15318:
#0: ffff88803baca480 (sb_writers#24){++++}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
7 locks held by syz-executor/16180:
#0: ffff888036014480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
#0: ffff888036014480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
#1: ffff888037f67078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
#2: ffff8880269aa3c8 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880269aa3c8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
#3: ffffffff8e12c638 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:184
#4: ffff888031dca0d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#4: ffff888031dca0d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006
#5: ffff88805b452300 (&devlink->lock_key#68){+.+.}-{4:4}, at: nsim_drv_probe+0xc3/0xbd0 drivers/net/netdevsim/dev.c:1637
#6: ffffffff8e8a5938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#6: ffffffff8e8a5938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2143
2 locks held by syz-executor/16448:
#0: ffffffff8edb4e40 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8edb4e40 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8edb4e40 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8e8a5938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e8a5938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8e8a5938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
3 locks held by syz.9.1379/16512:
5 locks held by sed/16515:
#0: ffff8880766b9e48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1a7/0x4a0 mm/mmap_lock.c:259
#1: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#1: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#1: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: ___pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288
#2: ffff88802f412a18 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#2: ffff88802f412a18 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x13e/0x210 mm/pgtable-generic.c:403
#3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1c1/0x3e0 kernel/locking/spinlock_rt.c:57
#4: ffff8880b8833cd0 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#4: ffff8880b8833cd0 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x284/0xa90 mm/swap.c:-1
8 locks held by syz.2.1380/16517:
1 lock held by syz.2.1380/16518:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(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: 82 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound linkwatch_event
RIP: 0010:__bfs kernel/locking/lockdep.c:1753 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1822/0x2cf0 kernel/locking/lockdep.c:5237
Code: 00 0f 83 8a 01 00 00 4e 8b 24 fd 60 38 bb 94 ff c0 25 ff 0f 00 00 89 05 bc 1e 1f 13 4d 85 e4 0f 84 b2 01 00 00 49 8b 44 24 10 <48> 85 c0 0f 84 1c 0d 00 00 8b 0d a7 1e 1f 13 39 48 5c 0f 84 67 ff
RSP: 0000:ffffc900015ae468 EFLAGS: 00000086
RAX: ffffffff9261f070 RBX: 00000000000003cd RCX: ffffffff95768888
RDX: ffffffff9548ff58 RSI: ffff88801b38aac0 RDI: 00000000000003cd
RBP: 023f4ea8824e3c8c R08: ffffc900015ae430 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff819cebf0 R12: ffffffff95768888
R13: ffff88801b38aac0 R14: ffff88801b389e40 R15: 0000000000000092
FS: 0000000000000000(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d2de9a01c8 CR3: 000000005866a000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
_raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:378
raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639
raw_spin_rq_lock kernel/sched/sched.h:1558 [inline]
task_rq_lock+0xbc/0x470 kernel/sched/core.c:739
class_task_rq_lock_constructor kernel/sched/sched.h:1858 [inline]
migrate_disable_switch kernel/sched/core.c:2350 [inline]
__schedule+0x164a/0x5070 kernel/sched/core.c:6749
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__list_add_valid_or_report+0x44/0x130 lib/list_debug.c:29
Code: 48 85 d2 0f 84 93 00 00 00 49 89 f6 49 89 ff 49 bd 00 00 00 00 00 fc ff df 4c 8d 63 08 4c 89 e5 48 c1 ed 03 42 80 7c 2d 00 00 <74> 08 4c 89 e7 e8 e2 7b 9a fd 4d 39 34 24 75 71 4d 89 f4 49 c1 ec
RSP: 0000:ffffc900015aea28 EFLAGS: 00000246
RAX: bff6ff2c8486ed00 RBX: ffff888027ef0500 RCX: 0000000000000000
RDX: ffff888027ef0500 RSI: ffff88806bdd2728 RDI: ffff888027ef06c0
RBP: 1ffff11004fde0a1 R08: ffffffff8ad40021 R09: ffffffff8d5ae940
R10: dffffc0000000000 R11: fffffbfff1db66af R12: ffff888027ef0508
R13: dffffc0000000000 R14: ffff88806bdd2728 R15: ffff888027ef06c0
__list_add_valid include/linux/list.h:96 [inline]
__list_add include/linux/list.h:158 [inline]
list_add include/linux/list.h:177 [inline]
ref_tracker_alloc+0x1f9/0x450 lib/ref_tracker.c:281
__netdev_tracker_alloc include/linux/netdevice.h:4400 [inline]
netdev_tracker_alloc include/linux/netdevice.h:4412 [inline]
netdev_get_by_index+0x79/0xb0 net/core/dev.c:1008
fib6_nh_init+0x1cd/0x1ff0 net/ipv6/route.c:3601
ip6_route_info_create_nh+0x16a/0xab0 net/ipv6/route.c:3901
addrconf_f6i_alloc+0x203/0x450 net/ipv6/route.c:4693
ipv6_add_addr+0x56e/0x10e0 net/ipv6/addrconf.c:1126
addrconf_add_linklocal+0x28f/0x600 net/ipv6/addrconf.c:3311
addrconf_addr_gen+0x490/0x580 net/ipv6/addrconf.c:3442
addrconf_init_auto_addrs+0x5c2/0xa00 net/ipv6/addrconf.c:-1
addrconf_notify+0xb1e/0x1050 net/ipv6/addrconf.c:3740
notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
netif_state_change+0x26f/0x380 net/core/dev.c:1584
linkwatch_do_dev+0x117/0x170 net/core/link_watch.c:186
__linkwatch_run_queue+0x56d/0x7e0 net/core/link_watch.c:244
linkwatch_event+0x4c/0x60 net/core/link_watch.c:304
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