INFO: task syz.0.5436:22784 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5436 state:D stack:26224 pid:22784 ppid:14743 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
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
blkdev_put+0xfe/0x710 block/bdev.c:930
blkdev_close+0x51/0x80 block/fops.c:514
__fput+0x22c/0x920 fs/file_table.c:320
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: 0033:0x7fb5bc99c799
RSP: 002b:00007ffee8ed9278 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fb5bcc17da0 RCX: 00007fb5bc99c799
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fb5bcc17da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007fb5bcc17cb0 R11: 0000000000000246 R12: 00000000000fd417
R13: 00007fb5bcc1609c R14: 00000000000fd15d R15: 00007ffee8ed9380
INFO: task syz.0.5436:22785 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5436 state:D stack:27856 pid:22785 ppid:14743 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
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
blkdev_put+0xfe/0x710 block/bdev.c:930
blkdev_close+0x51/0x80 block/fops.c:514
__fput+0x22c/0x920 fs/file_table.c:320
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: 0033:0x7fb5bc99c799
RSP: 002b:00007fb5bd93a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007fb5bcc15fa0 RCX: 00007fb5bc99c799
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004
RBP: 00007fb5bca32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb5bcc16038 R14: 00007fb5bcc15fa0 R15: 00007ffee8ed9118
INFO: task syz.0.5436:22786 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5436 state:D stack:27856 pid:22786 ppid:14743 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
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:832
blkdev_open+0x11e/0x2e0 block/fops.c:500
do_dentry_open+0x7e9/0x10d0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x2635/0x2ee0 fs/namei.c:3791
do_filp_open+0x1f1/0x430 fs/namei.c:3818
do_sys_openat2+0x150/0x4b0 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
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: 0033:0x7fb5bc95cfce
RSP: 002b:00007fb5bd918b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb5bd9196c0 RCX: 00007fb5bc95cfce
RDX: 0000000000000201 RSI: 00007fb5bd918c00 RDI: ffffffffffffff9c
RBP: 00007fb5bd918c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fb5bcc16128 R14: 00007fb5bcc16090 R15: 00007ffee8ed9118
Showing all locks held in the system:
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 getty/4030:
#0: ffff8880301ba098 (&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
3 locks held by kworker/u4:11/4582:
1 lock held by udevd/5031:
#0: ffff888142fd24c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:832
1 lock held by syz.0.5436/22784:
#0: ffff888142fd24c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfe/0x710 block/bdev.c:930
1 lock held by syz.0.5436/22785:
#0: ffff888142fd24c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfe/0x710 block/bdev.c:930
1 lock held by syz.0.5436/22786:
#0: ffff888142fd24c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:832
1 lock held by syz.1.6784/26873:
#0: ffffffff8cb331c0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4023
1 lock held by syz.3.6786/26879:
#0: ffffffff8cb331c0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4023
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4582 Comm: kworker/u4:11 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0xd86/0x7d10 kernel/locking/lockdep.c:5019
Code: 49 b8 00 00 00 00 00 fc ff df 85 c0 0f 84 dc 4c 00 00 4c 89 e7 4c 89 f6 ba 08 00 00 00 e8 c2 a7 00 00 85 c0 0f 84 b2 4c 00 00 <48> c7 c0 40 c1 bf 96 48 c1 e8 03 49 b8 00 00 00 00 00 fc ff df 42
RSP: 0018:ffffc90004b9f840 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000002 RCX: ffffffff8164fa44
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90af5240
RBP: ffffc90004b9fa90 R08: ffffffff90af5247 R09: 1ffffffff215ea48
R10: dffffc0000000000 R11: fffffbfff215ea49 R12: ffff88807aec3b80
R13: ffff88807aec4604 R14: ffff88807aec46b0 R15: ffff88807aec46d0
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556bc4ba28 CR3: 0000000063e70000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295