INFO: task syz.9.685:10162 blocked for mo[ 705.276474][ T39] INFO: task syz.9.685:10162 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.685 state:D stack:27408 pid:10162 tgid:10150 ppid:10055 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x1681/0x54c0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1659 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1776
__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:1496 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1570
__super_lock fs/super.c:60 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:122
__iterate_supers+0x126/0x250 fs/super.c:926
ksys_sync fs/sync.c:102 [inline]
__ia32_sys_sync+0xa0/0x120 fs/sync.c:111
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f601f60c819
RSP: 002b:00007f601d845028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f601f886090 RCX: 00007f601f60c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f601f886090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f601f886128 R14: 00007f601f886090 R15: 00007ffd94bff9d8
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:10/1181:
#0: ffff888066cd6138 ((wq_completion)loop7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline]
#0: ffff888066cd6138 ((wq_completion)loop7){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385
#1: ffffc90005b27c40 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline]
#1: ffffc90005b27c40 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385
#2: ffff8880264a1160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#2: ffff8880264a1160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0x125/0x11b0 drivers/block/loop.c:1953
2 locks held by getty/5556:
#0: ffff8880333550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cb62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
4 locks held by syz-executor/5785:
2 locks held by syz-executor/5800:
1 lock held by udevd/6032:
#0: ffff88802637f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:953
1 lock held by syz-executor/10062:
4 locks held by syz-executor/10068:
1 lock held by syz-executor/10089:
#0: ffffffff8dc0a0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline]
#0: ffffffff8dc0a0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1677
5 locks held by syz-executor/10108:
1 lock held by syz.9.685/10162:
#0: ffff888035ac20d0 (&type->s_umount_key#93){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888035ac20d0 (&type->s_umount_key#93){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
2 locks held by syz-executor/10291:
4 locks held by syz.3.920/11784:
2 locks held by syz.6.922/11799:
1 lock held by rm/11805:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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: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+0xfd3/0x1030 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: 10108 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__bfs kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1968/0x2cf0 kernel/locking/lockdep.c:5237
Code: 89 c1 81 e1 ff 0f 00 00 89 0d 88 af d9 13 2b 05 7e af d9 13 25 ff 0f 00 00 39 05 3f af d8 11 73 06 89 05 37 af d8 11 48 8b 02 <48> 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 4c 39 e8
RSP: 0018:ffffc9000460f220 EFLAGS: 00000006
RAX: ffffffff96122818 RBX: 00000000000003cd RCX: 00000000000001a8
RDX: ffffffff96121858 RSI: ffff88802768ca90 RDI: 00000000000003cd
RBP: b7261c4a5a4c1f12 R08: ffffc9000460f1e8 R09: 0000000000000020
R10: 0000000000000100 R11: ffffffff81a0d9a0 R12: ffffffff96121b68
R13: ffffffff9321bd10 R14: ffff88802768bd80 R15: 00000000000001a7
FS: 0000555585c04500(0000) GS:ffff888126209000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556ba06a28 CR3: 000000003b3a4000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73
ktime_get+0x45/0x220 kernel/time/timekeeping.c:965
clockevents_program_event+0x290/0x5f0 kernel/time/clockevents.c:360
__hrtimer_reprogram kernel/time/hrtimer.c:735 [inline]
hrtimer_force_reprogram kernel/time/hrtimer.c:746 [inline]
__hrtimer_start_range_ns kernel/time/hrtimer.c:1458 [inline]
hrtimer_start_range_ns+0xb28/0xef0 kernel/time/hrtimer.c:1491
hrtimer_start include/linux/hrtimer.h:220 [inline]
hrtick_cond_restart kernel/sched/core.c:924 [inline]
hrtick_schedule_exit kernel/sched/core.c:986 [inline]
finish_lock_switch kernel/sched/core.c:5123 [inline]
finish_task_switch+0x3cd/0xbe0 kernel/sched/core.c:5242
context_switch kernel/sched/core.c:5390 [inline]
__schedule+0x1689/0x54c0 kernel/sched/core.c:7188
preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7462
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:753
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5879
rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80
bdi_split_work_to_wbs+0x5ab/0x960 fs/fs-writeback.c:1083
sync_inodes_sb+0x218/0xc30 fs/fs-writeback.c:2941
sync_filesystem+0x179/0x250 fs/sync.c:64
generic_shutdown_super+0x77/0x2d0 fs/super.c:625
kill_block_super+0x44/0x90 fs/super.c:1725
ntfs3_kill_sb+0x44/0x1c0 fs/ntfs3/super.c:1875
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9c46bada57
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffec4e656c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f9c46c42048 RCX: 00007f9c46bada57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffec4e65780
RBP: 00007ffec4e65780 R08: 00007ffec4e66780 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffec4e66810
R13: 00007f9c46c42048 R14: 00000000000abfdd R15: 00007ffec4e66850