INFO: task syz.2.3444:23507 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.3444 state:D stack:26880 pid:23507 tgid:23503 ppid:21101 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7020
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
seq_read_iter+0xb7/0xe20 fs/seq_file.c:183
seq_read+0x369/0x480 fs/seq_file.c:163
do_loop_readv_writev fs/read_write.c:847 [inline]
vfs_readv+0x5aa/0x850 fs/read_write.c:1020
do_preadv fs/read_write.c:1132 [inline]
__do_sys_preadv fs/read_write.c:1179 [inline]
__se_sys_preadv fs/read_write.c:1174 [inline]
__x64_sys_preadv+0x197/0x2a0 fs/read_write.c:1174
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b5658f749
RSP: 002b:00007f7b5749c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00007f7b567e6180 RCX: 00007f7b5658f749
RDX: 0000000000000001 RSI: 00002000000005c0 RDI: 0000000000000004
RBP: 00007f7b56613f91 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7b567e6218 R14: 00007f7b567e6180 R15: 00007fffde6a2678
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e13f2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5586:
#0: ffff88814ea2c0a0 (&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+0x449/0x1460 drivers/tty/n_tty.c:2211
6 locks held by kworker/0:5/5899:
#0: ffff888020ac9948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc9000451fb80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffff888143fe3198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#2: ffff888143fe3198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899
#3: ffff888088127198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff888088127198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006
#4: ffff888088126160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#4: ffff888088126160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006
#5: ffff888143f42468 (hcd->bandwidth_mutex){+.+.}-{4:4}, at: usb_set_interface+0x353/0x1460 drivers/usb/core/message.c:1564
5 locks held by kworker/u8:15/5972:
5 locks held by kworker/u8:19/6565:
#0: ffff8880b863ab18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647
#1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
#2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085
#3: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
#3: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x4b3/0xf30 kernel/time/timer.c:1051
#4: ffffffff99db1290 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x87/0x540 lib/debugobjects.c:818
2 locks held by syz.2.3444/23504:
1 lock held by syz.2.3444/23507:
#0: ffff8880323011c8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:183
1 lock held by syz.3.3746/25070:
#0: ffffffff8e144d00 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3816
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
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]
__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:363 [inline]
watchdog+0xe40/0xe90 kernel/hung_task.c:557
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 23504 Comm: syz.2.3444 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x31/0x90 kernel/kcov.c:300
Code: 24 65 48 8b 14 25 08 b0 9f 92 65 8b 0d b8 f4 dd 10 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 6c 16 00 00 00 74 52 <8b> 8a 48 16 00 00 83 f9 03 75 47 48 8b 8a 50 16 00 00 44 8b 8a 4c
RSP: 0018:ffffc9000b137608 EFLAGS: 00000246
RAX: ffffffff8b59aa8d RBX: 0000000000000008 RCX: 0000000000000000
RDX: ffff8880303d1e80 RSI: 0000000000000008 RDI: 0000000000000000
RBP: ffffffff8bdfa0b7 R08: ffff8880303d1e80 R09: 0000000000000002
R10: 0000000000000025 R11: 0000000000000000 R12: ffffc9000b1376b9
R13: ffffffff8cb7be30 R14: 000000000000006c R15: 00000000000001b0
FS: 00007f7b574de6c0(0000) GS:ffff888125d25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9cd1fb6ad8 CR3: 000000009d59a000 CR4: 00000000003526f0
Call Trace:
format_decode+0x44d/0xe10 lib/vsprintf.c:2779
vsnprintf+0x102/0xee0 lib/vsprintf.c:2890
seq_vprintf fs/seq_file.c:392 [inline]
seq_printf+0x178/0x270 fs/seq_file.c:407
__io_uring_show_fdinfo io_uring/fdinfo.c:162 [inline]
io_uring_show_fdinfo+0xa8c/0x18a0 io_uring/fdinfo.c:261
seq_show+0x5ac/0x710 fs/proc/fd.c:68
traverse+0x1ee/0x580 fs/seq_file.c:112
seq_read_iter+0xd08/0xe20 fs/seq_file.c:196
seq_read+0x369/0x480 fs/seq_file.c:163
do_loop_readv_writev fs/read_write.c:847 [inline]
vfs_readv+0x5aa/0x850 fs/read_write.c:1020
do_preadv fs/read_write.c:1132 [inline]
__do_sys_preadv fs/read_write.c:1179 [inline]
__se_sys_preadv fs/read_write.c:1174 [inline]
__x64_sys_preadv+0x197/0x2a0 fs/read_write.c:1174
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b5658f749
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:00007f7b574de038 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00007f7b567e5fa0 RCX: 00007f7b5658f749
RDX: 0000000000000001 RSI: 00002000000005c0 RDI: 0000000000000004
RBP: 00007f7b56613f91 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7b567e6038 R14: 00007f7b567e5fa0 R15: 00007fffde6a2678