INFO: task syz.0.1163:10622 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1163 state:D stack:27560 pid:10622 ppid:5783 flags:0x00004004
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
blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
blkdev_open+0x152/0x360 block/fops.c:589
do_dentry_open+0x8c6/0x1500 fs/open.c:929
do_open fs/namei.c:3640 [inline]
path_openat+0x274b/0x3190 fs/namei.c:3797
do_filp_open+0x1c5/0x3d0 fs/namei.c:3824
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
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: 0033:0x7f6982b8df10
RSP: 002b:00007f6983a2db70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000002000 RCX: 00007f6982b8df10
RDX: 0000000000002000 RSI: 00007f6983a2dc10 RDI: 00000000ffffff9c
RBP: 00007f6983a2dc10 R08: 0000000000000000 R09: 002364626e2f7665
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007f6982de6128 R14: 00007f6982de6090 R15: 00007ffe3b647d18
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/1:1H/1057:
2 locks held by kworker/u4:8/2958:
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc9000c407d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc9000c407d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
2 locks held by getty/5553:
#0: ffff8880313820a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
5 locks held by kworker/u5:2/5785:
#0: ffff88805e279d38 ((wq_completion)hci1){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88805e279d38 ((wq_completion)hci1){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900043f7d00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900043f7d00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffff88807b688e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1d4/0x390 net/bluetooth/hci_sync.c:326
#3: ffff88807b6880b8 (&hdev->lock){+.+.}-{3:3}, at: hci_abort_conn_sync+0x1f7/0xdc0 net/bluetooth/hci_sync.c:5653
#4: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#4: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004
2 locks held by kworker/0:3/5825:
#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: ffffc9000475fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc9000475fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
3 locks held by kworker/u4:13/7276:
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90005acfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90005acfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
1 lock held by udevd/9655:
#0: ffff88802146a4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by syz.0.1163/10622:
#0: ffff88802146a4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
2 locks held by syz.5.1586/12108:
#0: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3511
#1: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#1: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004
=============================================
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 10/02/2025
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: 2958 Comm: kworker/u4:8 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:__lock_acquire+0x1085/0x7c80 kernel/locking/lockdep.c:5133
Code: 03 89 c3 81 e3 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 00 85 da 90 be 08 00 00 00 e8 43 de 75 00 48 0f a3 1d 9b 76 73 0f <0f> 83 40 01 00 00 48 69 c3 d0 00 00 00 48 8d 98 c0 03 71 90 49 b8
RSP: 0018:ffffc9000c407700 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 00000000000006cc RCX: ffffffff81670e5d
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da85d8
RBP: ffffc9000c407948 R08: ffffffff90da85df R09: 1ffffffff21b50bb
R10: dffffc0000000000 R11: fffffbfff21b50bc R12: 00000000eee9e3e4
R13: ffff88802b729e00 R14: 000000008a21ee8d R15: ffff88802b72a950
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31d09ff8 CR3: 000000000cb30000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 3a810b1eb6134bdc DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
batadv_nc_purge_paths+0xe7/0x3a0 net/batman-adv/network-coding.c:442
batadv_nc_worker+0x369/0x610 net/batman-adv/network-coding.c:722
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