INFO: task syz.0.2107:14092 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2107 state:D stack:25960 pid:14092 tgid:14092 ppid:5856 task_flags:0x400040 flags:0x00080002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
svc_disconnect+0x22a/0x400 net/atm/svc.c:64
svc_release+0x63/0xb0 net/atm/svc.c:94
__sock_release net/socket.c:662 [inline]
sock_close+0xc0/0x240 net/socket.c:1455
__fput+0x449/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6e36f8eec9
RSP: 002b:00007fff33f88d38 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f6e371e7da0 RCX: 00007f6e36f8eec9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f6e371e7da0 R08: 000000000000e4e4 R09: 0000001333f8902f
R10: 00000000005ee914 R11: 0000000000000246 R12: 000000000006b559
R13: 00007f6e371e5fa0 R14: ffffffffffffffff R15: 00007fff33f88e50
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5589:
#0: ffff88814de550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz.0.2107/14092:
#0: ffff88805d5b4708 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
#0: ffff88805d5b4708 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff88805d5b4708 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
1 lock held by syz.5.2887/16893:
3 locks held by syz.6.2911/16964:
#0: ffff88807fb02488 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
#0: ffff88807fb02488 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff88807fb02488 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
#1: ffff888039780258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1679 [inline]
#1: ffff888039780258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: isotp_release+0x43c/0xaf0 net/can/isotp.c:1203
#2: ffffffff8e142db8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e142db8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 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]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16893 Comm: syz.5.2887 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:match_held_lock+0x2/0xc0 kernel/locking/lockdep.c:5305
Code: 41 5f e9 91 dc 02 00 cc e8 fb f8 ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 56 <53> bb 01 00 00 00 48 39 77 10 74 6a 81 7f 20 00 00 20 00 72 5f 48
RSP: 0018:ffffc90000a08c50 EFLAGS: 00000083
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 5fc4e2347aa96900
RDX: 0000000000000001 RSI: ffff8880b873a058 RDI: ffff888034a7e618
RBP: ffff888034a7dac0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014117c R12: 0000000000000001
R13: 0000000000000046 R14: ffff8880b873a058 R15: ffff888034a7e618
FS: 00007fb2077cd6c0(0000) GS:ffff888125e0f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000cb1030 CR3: 0000000030090000 CR4: 00000000003526f0
Call Trace:
<IRQ>
__lock_pin_lock kernel/locking/lockdep.c:5624 [inline]
lock_pin_lock+0xac/0x190 kernel/locking/lockdep.c:5961
rq_pin_lock kernel/sched/sched.h:1794 [inline]
rq_lock kernel/sched/sched.h:1869 [inline]
ttwu_queue kernel/sched/core.c:3967 [inline]
try_to_wake_up+0x694/0x12b0 kernel/sched/core.c:4293
hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:2013
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
__sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1058
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 ab 6c 79 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> c3 aa 41 f6 65 8b 05 bc 38 43 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc9000de976a0 EFLAGS: 00000206
RAX: 5fc4e2347aa96900 RBX: 0000000000000a06 RCX: 5fc4e2347aa96900
RDX: 0000000000000006 RSI: ffffffff8d7e8753 RDI: 0000000000000001
RBP: ffffc9000de97728 R08: ffffffff8f9e0f77 R09: 1ffffffff1f3c1ee
R10: dffffc0000000000 R11: fffffbfff1f3c1ef R12: dffffc0000000000
R13: ffff88804364ac80 R14: ffff88803608f000 R15: 1ffff92001bd2ed4
sctp_recvmsg+0x825/0xd30 net/sctp/socket.c:2171
inet_recvmsg+0x24a/0x250 net/ipv4/af_inet.c:885
sock_recvmsg_nosec+0x11d/0x1c0 net/socket.c:1078
____sys_recvmsg+0x3aa/0x460 net/socket.c:2848
___sys_recvmsg+0x1b5/0x510 net/socket.c:2892
do_recvmmsg+0x307/0x770 net/socket.c:2987
__sys_recvmmsg net/socket.c:3061 [inline]
__do_sys_recvmmsg net/socket.c:3084 [inline]
__se_sys_recvmmsg net/socket.c:3077 [inline]
__x64_sys_recvmmsg+0x190/0x240 net/socket.c:3077
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb20698eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb2077cd038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fb206be5fa0 RCX: 00007fb20698eec9
RDX: 0000000004000169 RSI: 0000200000005000 RDI: 0000000000000003
RBP: 00007fb206a11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000060 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb206be6038 R14: 00007fb206be5fa0 R15: 00007ffdca127fc8
</TASK>