INFO: task syz-executor:4270 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:22032 pid:4270 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
wb_wait_for_completion+0x16f/0x290 fs/fs-writeback.c:191
__writeback_inodes_sb_nr+0x226/0x280 fs/fs-writeback.c:2670
sync_filesystem+0x9f/0x220 fs/sync.c:54
generic_shutdown_super+0x6b/0x340 fs/super.c:474
kill_block_super+0x7c/0xe0 fs/super.c:1470
deactivate_locked_super+0x93/0xf0 fs/super.c:332
cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191
task_work_run+0x1d0/0x260 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4c32f9d1d7
RSP: 002b:00007fff631458a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f4c33031c3b RCX: 00007f4c32f9d1d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff63145960
RBP: 00007fff63145960 R08: 00007fff63146960 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff631469f0
R13: 00007f4c33031c3b R14: 0000000000023d98 R15: 00007fff63146a30
Showing all locks held in the system:
2 locks held by kworker/u4:0/9:
#0: ffff8880b8e3ab18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:538
#1: ffff8880b8e27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x398/0x6d0 kernel/sched/psi.c:999
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2dfb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2e7d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by pvrusb2-context/2310:
#0: ffff888047224188 (&hdw->big_lock_mutex){+.+.}-{3:3}, at: pvr2_hdw_initialize+0xe1/0x3c10 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2326
#1: ffffffff8c9da110 (umhelper_sem){++++}-{3:3}, at: usermodehelper_read_trylock+0xf9/0x2b0 kernel/umh.c:218
3 locks held by kworker/u4:5/2957:
2 locks held by getty/4033:
#0: ffff88814cc7a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198
1 lock held by syz-executor/4270:
#0: ffff8880589940e0 (&type->s_umount_key#92){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
6 locks held by kworker/1:3/4271:
#0: ffff888144ea8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc90003e07d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#2: ffff888027eb9190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#2: ffff888027eb9190 (&dev->mutex){....}-{3:3}, at: hub_event+0x19f/0x5560 drivers/usb/core/hub.c:5845
#3: ffff888057ac4190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#3: ffff888057ac4190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x107/0x8a0 drivers/usb/core/hub.c:2305
#4: ffff888057ac1118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#4: ffff888057ac1118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline]
#4: ffff888057ac1118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb2/0x850 drivers/base/dd.c:1283
#5: ffff888047224188 (&hdw->big_lock_mutex){+.+.}-{3:3}, at: pvr2_hdw_disconnect+0x69/0x500 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2710
2 locks held by syz-executor/4279:
#0: ffff88807d58e0e0 (&type->s_umount_key#53){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#1: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
2 locks held by kworker/0:5/4333:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc900044efd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
2 locks held by kworker/u4:7/4365:
#0: ffff8880b8e3ab18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:538
#1: ffff8880b8e27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x398/0x6d0 kernel/sched/psi.c:999
4 locks held by udevd/4866:
#0: ffff888059cd49e0 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
#1: ffff888055c75088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x58/0x410 fs/kernfs/file.c:172
#2: ffff8880267aba00 (kn->active#24){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880267aba00 (kn->active#24){.+.+}-{0:0}, at: kernfs_seq_start+0xae/0x410 fs/kernfs/file.c:173
#3: ffff888057ac4190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:845 [inline]
#3: ffff888057ac4190 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x22/0x90 drivers/usb/core/sysfs.c:141
1 lock held by syz.7.1788/9022:
#0: ffff8880589940e0 (&type->s_umount_key#92){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755
1 lock held by sed/9144:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3622 Comm: syslogd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:__bfs kernel/locking/lockdep.c:1797 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1842 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2782 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3094 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3209 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3825 [inline]
RIP: 0010:__lock_acquire+0x3404/0x7d10 kernel/locking/lockdep.c:5049
Code: 4c 89 ff e8 0e e7 6e 00 48 ba 00 00 00 00 00 fc ff df 4d 8b 3f 4c 89 ac 24 80 00 00 00 4d 39 f7 75 0d e9 71 fb ff ff 4d 8b 3f <4d> 39 f7 74 45 49 8d 7f 30 48 89 f8 48 c1 e8 03 80 3c 10 00 74 0f
RSP: 0018:ffffc90003277280 EFLAGS: 00000046
RAX: 1ffffffff2692325 RBX: ffffffff933c0cd8 RCX: 0000000000000277
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff93491958
RBP: ffffc900032774d0 R08: ffffc90003277457 R09: ffffc90003277420
R10: dffffc0000000000 R11: fffff5200064ee8b R12: ffffffff92b3fbf0
R13: 00000000000003dd R14: ffffffff9047ed70 R15: ffffffff93495208
FS: 00007f16e80ddc80(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff588043c8 CR3: 000000002e93b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
do_write_seqcount_begin_nested include/linux/seqlock.h:515 [inline]
do_write_seqcount_begin include/linux/seqlock.h:541 [inline]
psi_group_change+0x1c2/0x1370 kernel/sched/psi.c:801
psi_task_change+0xdc/0x240 kernel/sched/psi.c:924
psi_enqueue kernel/sched/stats.h:143 [inline]
enqueue_task+0x26d/0x2b0 kernel/sched/core.c:2056
activate_task kernel/sched/core.c:2088 [inline]
ttwu_do_activate+0x1b7/0x320 kernel/sched/core.c:3700
ttwu_queue kernel/sched/core.c:3905 [inline]
try_to_wake_up+0x5de/0x1080 kernel/sched/core.c:4228
autoremove_wake_function+0x13/0xf0 kernel/sched/wait.c:419
__wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:107
__wake_up_common_lock kernel/sched/wait.c:138 [inline]
__wake_up_sync_key+0x11a/0x190 kernel/sched/wait.c:208
__unix_dgram_recvmsg+0x4c3/0xdc0 net/unix/af_unix.c:2478
sock_recvmsg_nosec net/socket.c:1022 [inline]
sock_recvmsg net/socket.c:1040 [inline]
sock_read_iter+0x2db/0x3a0 net/socket.c:1121
call_read_iter include/linux/fs.h:2259 [inline]
new_sync_read fs/read_write.c:389 [inline]
vfs_read+0x4a7/0xa00 fs/read_write.c:470
ksys_read+0x14c/0x250 fs/read_write.c:613
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f16e822d407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd704d21e0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f16e80ddc80 RCX: 00007f16e822d407
RDX: 00000000000000ff RSI: 0000561b8f8d6950 RDI: 0000000000000000
RBP: 0000561b8f8d6910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000561b8f8d6982
R13: 0000000000000000 R14: 0000561b8f8d6950 R15: 0000561b57929d98