INFO: task syz.4.277:7650 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.277 state:D stack:28936 pid:7650 ppid:6139 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
sync_bdevs+0x1af/0x330 block/bdev.c:1076
ksys_sync+0xba/0x150 fs/sync.c:105
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe80318f749
RSP: 002b:00007fe8013d5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fe8033e6090 RCX: 00007fe80318f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fe8033e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe8033e6128 R14: 00007fe8033e6090 R15: 00007ffffa09f8d8
INFO: task syz.4.277:7651 blocked for more than 146 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.277 state:D stack:27888 pid:7651 ppid:6139 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
sync_bdevs+0x1af/0x330 block/bdev.c:1076
ksys_sync+0xba/0x150 fs/sync.c:105
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe80318f749
RSP: 002b:00007fe8013b4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fe8033e6180 RCX: 00007fe80318f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fe8033e6180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe8033e6218 R14: 00007fe8033e6180 R15: 00007ffffa09f8d8
Showing all locks held in the system:
2 locks held by kworker/0:0/8:
#0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900000d7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900000d7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
4 locks held by kworker/0:2/789:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900039f7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900039f7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffff88804c675240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26c/0x3170 drivers/net/netdevsim/fib.c:1491
#3: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:566
2 locks held by getty/5527:
#0: ffff88814c8f60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
5 locks held by syz-executor/5775:
#0: ffff88807afa8e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88807afa8e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2709
#1: ffff88807afa80b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x4c9/0xfb0 net/bluetooth/hci_sync.c:5273
#2: ffffffff8e1225c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e1225c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa1/0x220 net/bluetooth/hci_conn.c:2540
#3: ffff888030cfeb38 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x70/0x660 net/bluetooth/l2cap_core.c:1763
#4: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#4: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004
3 locks held by kworker/1:5/5827:
2 locks held by kworker/0:5/5855:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900049bfd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900049bfd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
1 lock held by udevd/5999:
#0: ffff88802189e4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by syz.4.277/7650:
#0: ffff88802189e4c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1af/0x330 block/bdev.c:1076
1 lock held by syz.4.277/7651:
#0: ffff88802189e4c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1af/0x330 block/bdev.c:1076
2 locks held by syz-executor/8985:
3 locks held by syz-executor/9112:
#0: ffff88807abace70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88807abace70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2709
#1: ffff88807abac0b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x4c9/0xfb0 net/bluetooth/hci_sync.c:5273
#2: ffffffff8e1225c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e1225c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa1/0x220 net/bluetooth/hci_conn.c:2540
1 lock held by dhcpcd-run-hook/9276:
#0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:566
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 12 Comm: kworker/u4:1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:chacha_block_generic+0x2f6/0xda0 lib/crypto/chacha.c:86
Code: b6 04 10 84 c0 0f 85 1e 06 00 00 45 89 2f 44 8b 6c 24 5c 4d 8d 7e 1c 4c 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 25 06 00 00 <45> 03 2f 4c 8d 7b 1c 4c 8d 63 1f 4c 89 f8 48 c1 e8 03 0f b6 04 10
RSP: 0018:ffffc90000117680 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc900001177c0 RCX: 00000000b1da290e
RDX: dffffc0000000000 RSI: ffffc900001176e4 RDI: ffffc900001176ec
RBP: ffffc90000117770 R08: 0000000026470b36 R09: ffffc900001176e8
R10: 00000000ca995e65 R11: 0000000067addbdc R12: ffffc900001177db
R13: 00000000d6fa5baf R14: ffffc900001179a0 R15: ffffc900001179bc
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f22e13fb286 CR3: 000000002722d000 CR4: 00000000003506f0
Call Trace:
chacha20_block include/crypto/chacha.h:36 [inline]
crng_fast_key_erasure+0x150/0x240 drivers/char/random.c:305
crng_make_state+0x252/0x700 drivers/char/random.c:371
_get_random_bytes+0xd6/0x210 drivers/char/random.c:385
eth_random_addr include/linux/etherdevice.h:232 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:755 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x338/0xb00 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293