INFO: task syz.0.589:8311 blocked for more than 144 seconds.
Not tainted 6.16.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.589 state:D stack:25080 pid:8311 tgid:8311 ppid:5848 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
request_wait_answer fs/fuse/dev.c:565 [inline]
__fuse_request_send fs/fuse/dev.c:579 [inline]
__fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:673
fuse_simple_request fs/fuse/fuse_i.h:1237 [inline]
fuse_flush+0x5d4/0x800 fs/fuse/file.c:475
filp_flush+0xba/0x190 fs/open.c:1549
filp_close+0x1d/0x40 fs/open.c:1562
__range_close fs/file.c:752 [inline]
__do_sys_close_range fs/file.c:811 [inline]
__se_sys_close_range+0x359/0x650 fs/file.c:775
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7406f8ebe9
RSP: 002b:00007ffc47c685e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007f74071b7da0 RCX: 00007f7406f8ebe9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f74071b7da0 R08: 00000000000164ec R09: 0000001a47c688df
R10: 00007f74071b7cb0 R11: 0000000000000246 R12: 0000000000057722
R13: 00007f74071b6180 R14: ffffffffffffffff R15: 00007ffc47c68700
Showing all locks held in the system:
2 locks held by kworker/u8:2/30:
1 lock held by khungtaskd/32:
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5598:
#0: ffff8880304390a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz.3.964/9820:
2 locks held by syz.3.964/9823:
1 lock held by syz.4.972/9851:
#0: ffffffff8e144ac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
3 locks held by dhcpcd-run-hook/9866:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 978 Comm: kworker/0:2 Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events free_obj_work
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4857 [inline]
RIP: 0010:__lock_acquire+0x332/0xd20 kernel/locking/lockdep.c:5190
Code: e5 15 09 d5 09 cd 44 09 f5 41 89 6c c7 20 45 89 44 c7 24 4c 89 7c 24 10 4d 8d 34 c7 81 e5 ff 1f 00 00 48 0f a3 2d 0e 03 06 12 <73> 10 48 69 c5 c8 00 00 00 48 8d 80 f0 42 45 93 eb 40 83 3d 55 92
RSP: 0018:ffffc9000386f348 EFLAGS: 00000003
RAX: 000000000000000a RBX: ffffffff8e13f0e0 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802548da00
RBP: 0000000000000007 R08: 0000000000000000 R09: ffffffff8172aae5
R10: ffffc9000386f5f8 R11: fffff5200070dec1 R12: 0000000000020000
R13: 0000000000000000 R14: ffff88802548e540 R15: ffff88802548e4f0
FS: 0000000000000000(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2b3cd84198 CR3: 0000000075846000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4745
free_object_list lib/debugobjects.c:326 [inline]
free_obj_work+0x342/0x480 lib/debugobjects.c:513
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245