INFO: task syz.2.426:7494 blocked for more than 143 seconds.
Not tainted 6.16.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.426 state:D stack:25464 pid:7494 tgid:7493 ppid:5839 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
io_schedule+0x81/0xe0 kernel/sched/core.c:7724
folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317
folio_wait_writeback+0xb0/0x100 mm/page-writeback.c:3126
__filemap_fdatawait_range+0x147/0x230 mm/filemap.c:539
file_write_and_wait_range+0x275/0x330 mm/filemap.c:798
v9fs_file_fsync+0xcf/0x1a0 fs/9p/vfs_file.c:418
generic_write_sync include/linux/fs.h:3031 [inline]
netfs_file_write_iter+0x3d8/0x4a0 fs/netfs/buffered_write.c:494
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x54b/0xa90 fs/read_write.c:686
ksys_write+0x145/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7db438ebe9
RSP: 002b:00007f7db5196038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7db45b5fa0 RCX: 00007f7db438ebe9
RDX: 0000000000007fec RSI: 0000200000000300 RDI: 0000000000000007
RBP: 00007f7db4411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7db45b6038 R14: 00007f7db45b5fa0 R15: 00007ffcfbbd0dc8
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
6 locks held by kworker/1:0/24:
#0: ffff88823be1cf48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88823be1cf48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff888027f87198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff888027f87198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898
#3: ffff88807e2bf198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff88807e2bf198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x950 drivers/usb/core/hub.c:2335
#4: ffff88814370c160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#4: ffff88814370c160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
#4: ffff88814370c160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292
#5: ffffffff8ef805e8 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:225 [inline]
#5: ffffffff8ef805e8 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x2d8/0x5e0 drivers/input/input.c:2221
1 lock held by khungtaskd/31:
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by kworker/u8:8/1321:
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003fefbc0 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003fefbc0 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
2 locks held by getty/5594:
#0: ffff888034fc20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/u8:10/5970:
#0: ffff888030122148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888030122148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000abe7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000abe7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f509f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f509f08 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4193
3 locks held by kworker/u8:14/6109:
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000b3e7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000b3e7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f509f08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
2 locks held by syz.2.426/7494:
#0: ffff8880344e50b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1217
#1: ffff88807aef4428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
#1: ffff88807aef4428 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
1 lock held by syz.0.807/8899:
#0: ffffffff8f509f08 (rtnl_mutex){+.+.}-{4:4}, at: ppp_release+0x87/0x1f0 drivers/net/ppp/ppp_generic.c:420
2 locks held by syz.5.809/8904:
#0: ffffffff8f509f08 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline]
#0: ffffffff8f509f08 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3396
#1: ffffffff8e144bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#1: ffffffff8e144bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
1 lock held by rm/8924:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 49 Comm: kworker/u8:3 Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:153 [inline]
RIP: 0010:lock_acquire+0x154/0x360 kernel/locking/lockdep.c:5874
Code: 8d e8 e0 68 c8 09 b8 ff ff ff ff 65 0f c1 05 c3 95 fe 10 83 f8 01 0f 85 c9 00 00 00 48 c7 44 24 30 00 00 00 00 9c 8f 44 24 30 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00
RSP: 0018:ffffc90000b978d0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: acc9d41d79e1d700
RDX: 0000000000000000 RSI: ffffffff8db6fcc6 RDI: ffffffff8be1ba40
RBP: ffffffff8b34bfc7 R08: 0000000000000000 R09: ffffffff8b34bfc7
R10: dffffc0000000000 R11: fffffbfff1f4167f R12: 0000000000000000
R13: ffff888055c75598 R14: 0000000000000001 R15: 0000000000000246
FS: 0000000000000000(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f574fd5e1d4 CR3: 0000000075456000 CR4: 00000000003526f0
Call Trace:
__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+0xe7/0x3b0 net/batman-adv/network-coding.c:442
batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245