INFO: task syz-executor:7482 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21904 pid: 7482 ppid: 1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
wb_wait_for_completion+0x171/0x290 fs/fs-writeback.c:191
sync_inodes_sb+0x1bd/0x950 fs/fs-writeback.c:2781
sync_filesystem+0x16d/0x220 fs/sync.c:64
generic_shutdown_super+0x6b/0x300 fs/super.c:448
kill_block_super+0x7c/0xe0 fs/super.c:1427
deactivate_locked_super+0x93/0xf0 fs/super.c:335
cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f94c944cf17
RSP: 002b:00007ffc916ab7b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f94c94b571f RCX: 00007f94c944cf17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc916ab870
RBP: 00007ffc916ab870 R08: 00007ffc916ac870 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc916ac900
R13: 00007f94c94b571f R14: 0000000000037ea0 R15: 00007ffc916ac940
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:1/144:
#0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000172fd00 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by getty/3941:
#0: ffff88807f019098 (&tty->ldisc_sem
){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
2 locks held by kworker/0:7/4253:
3 locks held by kworker/0:10/4308:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc900044bfd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2:
ffffffff8c3211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
ffffffff8c3211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
3 locks held by kworker/0:11/4451:
#0: ffff88802b55b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc90002fbfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffff88802a77a7e8 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x5c/0x1050 kernel/sched/core.c:4049
2 locks held by kworker/0:16/4564:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000302fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
3 locks held by kworker/1:11/5399:
#0:
ffff88802b55b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000150fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2:
ffffffff8d434808
(rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xca/0x1540 net/ipv6/addrconf.c:4110
2 locks held by kworker/1:18/6204:
2 locks held by dhcpcd/6333:
#0: ffff888060058210 (&sb->s_type->i_mutex_key#11
){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
){+.+.}-{3:3}, at: __sock_release net/socket.c:650 [inline]
){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1346
#1: ffffffff8c3211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c3211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
3 locks held by kworker/u4:10/7262:
#0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc900038afd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2:
ffff8880b903a358
(&rq->__lock){-.-.}-{2:2}, at: __rq_lockp kernel/sched/sched.h:1191 [inline]
(&rq->__lock){-.-.}-{2:2}, at: finish_lock_switch+0x60/0x280 kernel/sched/core.c:4801
3 locks held by kworker/u4:12/7266:
4 locks held by kworker/u4:13/7268:
#0:
ffff888018fa8138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc900038efd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
#3: ffff88806028cbe8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x25b/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4578
2 locks held by kworker/u4:16/7276:
2 locks held by syz-executor/7482:
#0:
ffff888060df00e0
(&type->s_umount_key#61){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
#1: ffff88814755c7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff88814755c7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a1/0x950 fs/fs-writeback.c:2779
2 locks held by syz-executor/10563:
#0: ffffffff8d434808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d434808 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ee/0xf30 net/core/rtnetlink.c:5681
#1: ffff888059ce13e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_open+0x223/0x420 drivers/net/wireguard/device.c:49
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 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+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7262 Comm: kworker/u4:10 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:769 [inline]
RIP: 0010:batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline]
RIP: 0010:batadv_nc_worker+0x1d3/0x5c0 net/batman-adv/network-coding.c:723
Code: 4d 85 ed 74 10 49 81 c5 38 fe ff ff 74 07 e8 c4 48 ea f7 eb b9 e8 bd 48 ea f7 e8 78 67 2b 00 89 c5 31 ff 89 c6 e8 0d 4c ea f7 <85> ed 74 15 e8 94 fa d5 f7 84 c0 74 18 e8 9b 48 ea f7 48 8b 6c 24
RSP: 0018:ffffc900038afbe0 EFLAGS: 00000293
RAX: ffffffff898ec7a3 RBX: dffffc0000000000 RCX: ffff888025480000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: dffffc0000000000 R09: 1ffffffff2036e18
R10: dffffc0000000000 R11: fffffbfff2036e19 R12: 0000000000000050
R13: fffffffffffffe38 R14: ffff88801ade8c80 R15: ffff88801a1be350
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc0a08cea10 CR3: 0000000055561000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287