INFO: task syz.2.863:8255 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.863 state:D stack:25640 pid:8255 tgid:8255 ppid:5635 task_flags:0x400040 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
request_wait_answer fs/fuse/dev.c:743 [inline]
__fuse_request_send fs/fuse/dev.c:757 [inline]
fuse_chan_send+0x1065/0x1ac0 fs/fuse/dev.c:833
fuse_simple_request fs/fuse/fuse_i.h:1012 [inline]
fuse_flush+0x66e/0x8b0 fs/fuse/file.c:504
filp_flush+0xbd/0x190 fs/open.c:1471
filp_close+0x1d/0x40 fs/open.c:1484
__range_close fs/file.c:793 [inline]
__do_sys_close_range fs/file.c:854 [inline]
__se_sys_close_range+0x3d3/0x900 fs/file.c:818
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f117079e0d9
RSP: 002b:00007f1170b4fba8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007f1170a27da0 RCX: 00007f117079e0d9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f1170a27da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007f1170a27cb0 R11: 0000000000000246 R12: 0000000000043e01
R13: 00007f1170a2609c R14: 0000000000043c78 R15: 00007f1170a26090
INFO: task syz.2.863:8256 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.863 state:D stack:24968 pid:8256 tgid:8255 ppid:5635 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2ca/0x5e0 kernel/sched/completion.c:153
fuse_direct_IO+0xa94/0x12d0 fs/fuse/file.c:2814
generic_file_direct_write+0x1d0/0x3f0 mm/filemap.c:4298
fuse_cache_write_iter fs/fuse/file.c:1531 [inline]
fuse_file_write_iter+0xa88/0x11a0 fs/fuse/file.c:1876
do_iter_readv_writev+0x612/0x8c0 fs/read_write.c:-1
vfs_writev+0x343/0x990 fs/read_write.c:1058
do_writev+0x154/0x2e0 fs/read_write.c:1104
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f117079e0d9
RSP: 002b:00007f1171611028 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f1170a25fa0 RCX: 00007f117079e0d9
RDX: 0000000000000020 RSI: 0000200000000400 RDI: 0000000000000009
RBP: 00007f1170835024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1170a26038 R14: 00007f1170a25fa0 R15: 00007f1170b4fa48
Showing all locks held in the system:
3 locks held by kworker/1:1/29:
#0: ffff888022af2940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff888022af2940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90000a47c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90000a47c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffff88802a38d1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#2: ffff88802a38d1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30 drivers/usb/core/hub.c:5907
1 lock held by khungtaskd/31:
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5371:
#0: ffff888036cee0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
2 locks held by syz.2.863/8256:
#0: ffff88807d2fe450 (sb_writers#14){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#0: ffff88807d2fe450 (sb_writers#14){.+.+}-{0:0}, at: vfs_writev+0x2af/0x990 fs/read_write.c:1056
#1: ffff8880560fc4c0 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#1: ffff8880560fc4c0 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: fuse_cache_write_iter fs/fuse/file.c:1518 [inline]
#1: ffff8880560fc4c0 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: fuse_file_write_iter+0x344/0x11a0 fs/fuse/file.c:1876
1 lock held by syz.3.1441/9992:
#0: ffff888029f30260 (sk_lock-AF_SMC){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#0: ffff888029f30260 (sk_lock-AF_SMC){+.+.}-{0:0}, at: smc_connect+0xbd/0xdb0 net/smc/af_smc.c:1671
1 lock held by syz.1.1446/10009:
#0: ffffffff8f457e00 (tty_mutex){+.+.}-{4:4}, at: tty_release_struct+0xae/0xd0 drivers/tty/tty_io.c:1691
1 lock held by syz.1.1448/10016:
#0: ffffffff8eb5fe38 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3857
1 lock held by syz.0.1450/10022:
#0: ffffffff8eb5fe38 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3857
=============================================
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 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:preempt_count_add+0x61/0x190 kernel/sched/core.c:5985
Code: 65 41 d8 11 65 01 3d 5e 41 d8 11 48 c7 c0 80 05 78 9a 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 e5 00 00 00 83 3d 8f 96 e3 18 00 <75> 11 65 8b 05 36 41 d8 11 0f b6 c0 3d f5 00 00 00 73 5d 65 8b 05
RSP: 0018:ffffc90000a08da8 EFLAGS: 00000046
RAX: 0000000000000004 RBX: ffff8880b87281c0 RCX: ffffffff9a780503
RDX: 0000000000010000 RSI: ffffffff8c4bbf60 RDI: 0000000000000001
RBP: ffff88807ba4a300 R08: ffffffff90574837 R09: 1ffffffff20ae906
R10: dffffc0000000000 R11: fffffbfff20ae907 R12: ffff8880b87281c0
R13: 0000000000000001 R14: ffff8880b8728360 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125055000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33a0cff8 CR3: 000000000e946000 CR4: 00000000003526f0
Call Trace:
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:141 [inline]
_raw_spin_lock_irq+0x21/0x50 kernel/locking/spinlock.c:174
__run_hrtimer kernel/time/hrtimer.c:2036 [inline]
__hrtimer_run_queues+0x466/0xa10 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: cb 7e 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 be 18 00 fb f4 4c 07 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e40 EFLAGS: 00000242
RAX: 000000000092ebc1 RBX: ffffffff819b4450 RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8e228edb RDI: ffffffff8c4bbf80
RBP: ffffc90000197f10 R08: ffff8880b87338db R09: 1ffff110170e671b
R10: dffffc0000000000 R11: ffffed10170e671c R12: 0000000000000000
R13: 1ffff11003c53000 R14: 1ffff92000032fd0 R15: dffffc0000000000
arch_safe_halt arch/x86/kernel/process.c:767 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:768
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x2e0/0x540 kernel/sched/idle.c:355
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x157