INFO: task syz-executor:5604 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21752 pid:5604 tgid:5604 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x16d8/0x55e0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7564
rwbase_write_lock+0x3cf/0x720 kernel/locking/rwbase_rt.c:273
__super_lock fs/super.c:58 [inline]
__super_lock_excl fs/super.c:73 [inline]
deactivate_super+0xa9/0xe0 fs/super.c:508
cleanup_mnt+0x3d3/0x460 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+0x193/0x6b0 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:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2f52cfe097
RSP: 002b:00007ffd200bdd38 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f2f52d921ca RCX: 00007f2f52cfe097
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd200bddf0
RBP: 00007ffd200bddf0 R08: 00007ffd200bedf0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd200bee80
R13: 00007f2f52d921ca R14: 00000000000260eb R15: 00007ffd200beec0
INFO: task syz.3.114:6506 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.114 state:D stack:25576 pid:6506 tgid:6505 ppid:5613 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x16d8/0x55e0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
jfs_flush_journal+0x719/0xf50 fs/jfs/jfs_logmgr.c:1561
jfs_sync_fs+0x7d/0xa0 fs/jfs/super.c:649
dquot_quota_sync+0xd1/0x490 fs/quota/dquot.c:782
__iterate_supers+0x137/0x240 fs/super.c:927
quota_sync_all fs/quota/quota.c:69 [inline]
__do_sys_quotactl fs/quota/quota.c:938 [inline]
__se_sys_quotactl+0x3a0/0x9d0 fs/quota/quota.c:917
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: 0033:0x7fb1113bce59
RSP: 002b:00007fb10f60e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fb111635fa0 RCX: 00007fb1113bce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007fb111452d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb111636038 R14: 00007fb111635fa0 R15: 00007ffe46263988
Showing all locks held in the system:
6 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/38:
#0: ffffffff8ddc7b60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8ddc7b60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8ddc7b60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by udevd/4970:
#0: ffff8880262874c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:953
2 locks held by getty/5354:
#0: ffff888032c410a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1390 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5604:
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
1 lock held by udevd/5726:
#0: ffff88803788a480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
1 lock held by udevd/5838:
#0: ffff8880262874c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:953
2 locks held by udevd/5919:
1 lock held by syz.3.114/6506:
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.0.157/6824:
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.4.168/6944:
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.2.211/7260:
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88803a9ca0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz-executor/7395:
#0: ffff88807e442480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
5 locks held by syz.5.334/8023:
3 locks held by syz.8.333/8025:
1 lock held by syz.7.335/8044:
4 locks held by syz.6.336/8028:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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+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: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: btrfs-cache btrfs_work_helper
RIP: 0010:__bfs kernel/locking/lockdep.c:1753 [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+0x17a5/0x2cc0 kernel/locking/lockdep.c:5237
Code: 00 00 0f 83 84 01 00 00 4e 8b 3c e5 00 38 50 95 ff c0 25 ff 0f 00 00 89 05 58 b6 b0 13 4d 85 ff 0f 84 ac 01 00 00 49 8b 47 10 <48> 85 c0 0f 84 18 0d 00 00 8b 0d 44 b6 b0 13 39 48 5c 0f 84 6a ff
RSP: 0018:ffffc90000127078 EFLAGS: 00000082
RAX: ffffffff92f82bb0 RBX: 00000000000003cd RCX: ffffffff92f6f298
RDX: ffffffff92fbb878 RSI: ffff88801ca9e928 RDI: 00000000000003cd
RBP: c8c82d1cba21f950 R08: ffffc90000127040 R09: 0000000000000020
R10: 0000000000000000 R11: ffffffff81a054b0 R12: 0000000000000413
R13: ffff88801ca9e928 R14: ffff88801ca9dc40 R15: ffffffff95e86598
FS: 0000000000000000(0000) GS:ffff8881264a1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff12de2e000 CR3: 0000000078a22000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
lock_hrtimer_base kernel/time/hrtimer.c:191 [inline]
hrtimer_start_range_ns+0xc3/0xee0 kernel/time/hrtimer.c:1489
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:5124 [inline]
finish_task_switch+0x3c7/0xbc0 kernel/sched/core.c:5243
context_switch kernel/sched/core.c:5391 [inline]
__schedule+0x16e0/0x55e0 kernel/sched/core.c:7189
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
class_preempt_destructor include/linux/preempt.h:468 [inline]
raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:102 [inline]
rtlock_slowlock kernel/locking/rtmutex.c:1918 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x316/0x400 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:45 [inline]
caching_thread+0x1696/0x1e20 fs/btrfs/block-group.c:909
btrfs_work_helper+0x338/0xc30 fs/btrfs/async-thread.c:312
process_one_work kernel/workqueue.c:3314 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478
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