INFO: task kworker/u4:5:1174 blocked for more than 143 seconds.
Not tainted 6.1.119-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:5 state:D stack:22368 pid:1174 ppid:2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:3)
Call Trace:
context_switch kernel/sched/core.c:5241 [inline]
__schedule+0x143f/0x4570 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
exfat_write_inode+0x65/0x110 fs/exfat/inode.c:94
write_inode fs/fs-writeback.c:1460 [inline]
__writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677
writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903
__writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974
wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079
wb_check_old_data_flush fs/fs-writeback.c:2179 [inline]
wb_do_writeback fs/fs-writeback.c:2232 [inline]
wb_workfn+0xbec/0x1020 fs/fs-writeback.c:2260
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Showing all locks held in the system:
3 locks held by kworker/u4:0/9:
#0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc900000e7d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8d32b110 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8d32b910 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by rcu_preempt/16:
#0: ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa8/0x140 kernel/sched/core.c:545
1 lock held by khungtaskd/28:
#0: ffffffff8d32af40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d32af40 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d32af40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
4 locks held by kworker/u4:5/1174:
#0: ffff888018c0c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc900051bfd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffff88807628c0e0 (&type->s_umount_key#65){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415
#3: ffff88807628a0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:94
2 locks held by getty/4003:
#0: ffff8880306fe098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198
3 locks held by syz-executor/4247:
#0: ffff88807d71d0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:508 [inline]
#0: ffff88807d71d0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1ff/0x500 net/bluetooth/hci_core.c:2707
#1: ffff88807d71c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0xfc0 net/bluetooth/hci_sync.c:5048
#2: ffffffff8e661c48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1799 [inline]
#2: ffffffff8e661c48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x2a0 net/bluetooth/hci_conn.c:2503
3 locks held by syz-executor/4248:
3 locks held by syz-executor/4250:
3 locks held by kworker/0:5/4296:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc900046f7d20 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8d330538 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#2: ffffffff8d330538 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962
3 locks held by syz-executor/4456:
2 locks held by kworker/0:17/6052:
#0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc900049cfd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
4 locks held by syz.4.398/6333:
#0: ffff88807d7190b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:508 [inline]
#0: ffff88807d7190b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1ff/0x500 net/bluetooth/hci_core.c:2707
#1: ffff88807d718078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0xfc0 net/bluetooth/hci_sync.c:5048
#2: ffffffff8e661c48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1799 [inline]
#2: ffffffff8e661c48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x2a0 net/bluetooth/hci_conn.c:2503
#3: ffffffff8d330538 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#3: ffffffff8d330538 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962
3 locks held by syz.2.399/6339:
#0: ffff8880783150b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:508 [inline]
#0: ffff8880783150b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1ff/0x500 net/bluetooth/hci_core.c:2707
#1: ffff888078314078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0xfc0 net/bluetooth/hci_sync.c:5048
#2: ffffffff8e661c48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1799 [inline]
#2: ffffffff8e661c48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x2a0 net/bluetooth/hci_conn.c:2503
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1ae/0x3f0 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+0xf88/0xfd0 kernel/hung_task.c:377
kthread+0x28d/0x320 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: 4668 Comm: kworker/u4:15 Not tainted 6.1.119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:lock_acquire+0x1ef/0x5a0 kernel/locking/lockdep.c:5662
Code: 31 c9 41 f7 c7 00 02 00 00 41 0f 94 c1 48 8b 7c 24 20 44 89 f6 8b 54 24 1c 48 8b 4c 24 30 4c 8b 44 24 38 6a 00 6a 00 ff 75 10 74 24 40 e8 e8 04 00 00 48 83 c4 20 48 c7 c7 40 13 0c 8b e8 98
RSP: 0018:ffffc9000522f868 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffffc9000522f8e0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff975f1118
RBP: ffffc9000522f9c8 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000a45f18
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000046
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6f6fd63360 CR3: 000000000d08e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
__debug_check_no_obj_freed lib/debugobjects.c:968 [inline]
debug_check_no_obj_freed+0xd8/0x4e0 lib/debugobjects.c:1009
slab_free_hook mm/slub.c:1699 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0x241/0x510 mm/slub.c:3683
nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
nsim_dev_trap_report_work+0x75d/0xab0 drivers/net/netdevsim/dev.c:851
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295