INFO: task syz-executor:4266 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:21856 pid:4266 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
wb_wait_for_completion+0x162/0x280 fs/fs-writeback.c:191
sync_inodes_sb+0x1b8/0x9e0 fs/fs-writeback.c:2750
sync_filesystem+0x16d/0x220 fs/sync.c:64
generic_shutdown_super+0x6b/0x340 fs/super.c:474
kill_block_super+0x7c/0xe0 fs/super.c:1470
deactivate_locked_super+0x93/0xf0 fs/super.c:332
cleanup_mnt+0x463/0x4f0 fs/namespace.c:1191
task_work_run+0x1ca/0x250 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:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f883e3909f7
RSP: 002b:00007ffda6fb18a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f883e411d7d RCX: 00007f883e3909f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffda6fb1960
RBP: 00007ffda6fb1960 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffda6fb29f0
R13: 00007f883e411d7d R14: 0000000000019970 R15: 00007ffda6fb2a30
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2b630 (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: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
2 locks held by kworker/0:1/14:
1 lock held by khungtaskd/28:
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
4 locks held by kworker/u4:3/51:
#0: ffff888141e67938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90000bc7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
#3: ffffffff8cb1ee60 (console_owner){..-.}-{0:0}, at: console_lock_spinning_enable kernel/printk/printk.c:1818 [inline]
#3: ffffffff8cb1ee60 (console_owner){..-.}-{0:0}, at: console_emit_next_record+0x82d/0xc90 kernel/printk/printk.c:2774
2 locks held by kworker/u4:4/75:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc900015d7d00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
2 locks held by getty/4029:
#0: ffff88814d4db098 (&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+0x41b/0x1380 drivers/tty/n_tty.c:2198
2 locks held by syz-executor/4266:
#0: ffff88807414e0e0 (&type->s_umount_key#63){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffff8880248ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff8880248ce7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x19c/0x9e0 fs/fs-writeback.c:2748
2 locks held by kworker/0:4/4315:
2 locks held by kworker/0:9/4375:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004a57d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
3 locks held by kworker/0:15/4867:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90006537d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffff888079f1d240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26b/0x32b0 drivers/net/netdevsim/fib.c:1491
2 locks held by kworker/1:17/5869:
2 locks held by dhcpcd/8064:
#0: ffff888073564130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
#0: ffff888073564130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
#1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
=============================================
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 10/02/2025
Call Trace:
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 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: 3626 Comm: klogd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:trace_hardirqs_on_prepare+0x0/0x190 kernel/trace/trace_preemptirq.c:29
Code: 89 f7 49 89 d6 e8 00 d5 49 00 4c 89 f2 e9 35 ff ff ff 0f 1f 84 00 00 00 00 00 e9 fb a1 03 00 66 2e 0f 1f 84 00 00 00 00 00 90 <41> 57 41 56 41 54 53 65 8b 05 4a 05 7c 7e 85 c0 74 7b 65 8b 05 4f
RSP: 0018:ffffc900032a7f08 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc900032a7f58 RCX: ffffffff812f1d20
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88807cda8000
RBP: ffffc900032a7f48 R08: dffffc0000000000 R09: ffffed100f9b5001
R10: ffffed100f9b5001 R11: 1ffff1100f9b5000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc900032a7f58 R15: 0000000000000067
FS: 00007f2f71cd3c80(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056108bc80078 CR3: 000000002e217000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__exit_to_user_mode kernel/entry/common.c:136 [inline]
syscall_exit_to_user_mode+0x1b/0x40 kernel/entry/common.c:305
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2f71e9da37
Code: 73 01 c3 48 8b 0d c1 f3 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 f3 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe980e2c08 EFLAGS: 00000206 ORIG_RAX: 0000000000000067
RAX: 00000000000003e9 RBX: 00007f2f7203d490 RCX: 00007f2f71e9da37
RDX: 00000000000003ff RSI: 00007f2f7203d490 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000206 R12: 00007f2f7203d490
R13: 00007f2f7201adfe R14: 00007f2f7203d4f6 R15: 00007f2f7203d4f6