INFO: task syz.4.603:13680 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.603 state:D stack:28984 pid:13680 tgid:13676 ppid:12433 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1539
__super_lock fs/super.c:60 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:122
__iterate_supers+0x126/0x290 fs/super.c:926
ksys_sync+0xa0/0x170 fs/sync.c:102
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd68453bf79
RSP: 002b:00007fd68278e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fd6847b5fa0 RCX: 00007fd68453bf79
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd6847b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd6847b6038 R14: 00007fd6847b5fa0 R15: 00007ffef182e508
INFO: task syz.4.603:13683 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.603 state:D stack:25496 pid:13683 tgid:13676 ppid:12433 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1539
__super_lock fs/super.c:60 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:122
__iterate_supers+0x126/0x290 fs/super.c:926
ksys_sync+0xa0/0x170 fs/sync.c:102
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd68453bf79
RSP: 002b:00007fd68276d028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fd6847b6090 RCX: 00007fd68453bf79
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd6847b6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd6847b6128 R14: 00007fd6847b6090 R15: 00007ffef182e508
Showing all locks held in the system:
1 lock held by khungtaskd/37:
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:10/2239:
#0: ffff8880316b2938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff8880316b2938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc900067dfc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc900067dfc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
#2: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4194
2 locks held by getty/5555:
#0: ffff888036e6f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/0:5/5876:
#0: ffff88813fe3bd38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88813fe3bd38 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc900051b7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc900051b7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
#2: ffff88805ad74260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490
2 locks held by syz-executor/9091:
2 locks held by kworker/0:9/12796:
1 lock held by syz.4.603/13680:
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.4.603/13683:
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.5.636/13883:
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by udevd/14257:
1 lock held by syz.2.688/14309:
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.0.703/14499:
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888024b220d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
3 locks held by syz-executor/14740:
2 locks held by syz.9.742/14997:
3 locks held by syz.7.741/14994:
2 locks held by syz.1.743/14999:
1 lock held by rm/15000:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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:161 [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+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14192 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:lockdep_hardirqs_on_prepare+0x97/0x260 kernel/locking/lockdep.c:4407
Code: 0d 00 0f 85 62 01 00 00 85 c0 75 0f 65 8b 05 6c fa 89 10 85 c0 0f 85 a1 01 00 00 65 48 8b 1d 28 b8 89 10 48 8b 83 58 0b 00 00 <48> 89 83 40 0b 00 00 48 c7 c7 83 05 36 8d e8 d6 75 73 09 65 ff 05
RSP: 0018:ffffc900045efb80 EFLAGS: 00000046
RAX: cad4c17b9ae5c20b RBX: ffff888037099e00 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8b861560 RDI: ffffffff8b861520
RBP: 0000000000000001 R08: ffffffff8f492877 R09: 1ffffffff1e9250e
R10: dffffc0000000000 R11: fffffbfff1e9250f R12: dffffc0000000000
R13: ffff8880b8940358 R14: ffff8880b8940318 R15: ffff888037099e00
FS: 000055555fac1500(0000) GS:ffff888126695000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f22eee08000 CR3: 00000000371fc000 CR4: 00000000003526f0
Call Trace:
trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:78
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline]
_raw_spin_unlock_irqrestore+0x30/0x80 kernel/locking/spinlock.c:194
rt_mutex_slowtrylock kernel/locking/rtmutex.c:1395 [inline]
__rt_spin_trylock kernel/locking/spinlock_rt.c:106 [inline]
rt_spin_trylock+0xd2/0x2b0 kernel/locking/spinlock_rt.c:118
alloc_from_pcs mm/slub.c:4633 [inline]
slab_alloc_node mm/slub.c:4773 [inline]
__kmalloc_cache_noprof+0x1a0/0x690 mm/slub.c:5292
kmalloc_noprof include/linux/slab.h:962 [inline]
slab_free_hook mm/slub.c:2622 [inline]
slab_free mm/slub.c:6082 [inline]
kmem_cache_free+0x154/0x690 mm/slub.c:6212
sk_prot_free net/core/sock.c:2282 [inline]
__sk_destruct+0x617/0x880 net/core/sock.c:2384
inet_release+0x143/0x190 net/ipv4/af_inet.c:437
__sock_release net/socket.c:662 [inline]
sock_close+0xc3/0x240 net/socket.c:1455
__fput+0x45e/0xa80 fs/file_table.c:469
fput_close_sync+0x11f/0x240 fs/file_table.c:574
__do_sys_close fs/open.c:1509 [inline]
__se_sys_close fs/open.c:1494 [inline]
__x64_sys_close+0x7e/0x110 fs/open.c:1494
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdf2054c84e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffdb11f49d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 000055555fac1500 RCX: 00007fdf2054c84e
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffdb11f4a7c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000e
R13: 000055555fad49f0 R14: 0000000000158855 R15: 00007ffdb11f4ad0