INFO: task kworker/u8:7:3478 blocked for more than 143 seconds.
Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:7 state:D stack:20944 pid:3478 tgid:3478 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:3)
Call Trace:
context_switch kernel/sched/core.c:5377 [inline]
__schedule+0x18bc/0x4c40 kernel/sched/core.c:6764
__schedule_loop kernel/sched/core.c:6841 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6856
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1d7/0x220 kernel/locking/rwsem.c:1578
f2fs_down_write fs/f2fs/f2fs.h:2191 [inline]
f2fs_balance_fs+0x5a9/0x810 fs/f2fs/segment.c:454
f2fs_write_inode+0x3a7/0x540 fs/f2fs/inode.c:803
write_inode fs/fs-writeback.c:1525 [inline]
__writeback_single_inode+0x708/0x10d0 fs/fs-writeback.c:1745
writeback_sb_inodes+0x820/0x1360 fs/fs-writeback.c:1976
__writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2047
wb_writeback+0x427/0xb80 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xb94/0x1080 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
#0: ffffffff8e93dc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#0: ffffffff8e93dc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:996
1 lock held by khungtaskd/30:
#0: ffffffff8e9387a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e9387a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e9387a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
4 locks held by kworker/u8:7/3478:
#0: ffff88801e6cb948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801e6cb948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
#1: ffffc9000ce87c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000ce87c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
#2: ffff88802d69c0e0 (&type->s_umount_key#75){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
#3: ffff88807f0b9350 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2191 [inline]
#3: ffff88807f0b9350 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x5a9/0x810 fs/f2fs/segment.c:454
3 locks held by kworker/u8:8/3520:
2 locks held by getty/5581:
#0: ffff8880362000a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5821:
#0: ffffffff8e93dc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#0: ffffffff8e93dc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:996
6 locks held by syz.3.114/6946:
2 locks held by syz.1.189/7578:
#0: ffff88802d69c0e0 (&type->s_umount_key#75){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802d69c0e0 (&type->s_umount_key#75){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff8880250c07d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880250c07d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
2 locks held by syz.1.189/7582:
#0: ffff88802d69c0e0 (&type->s_umount_key#75){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802d69c0e0 (&type->s_umount_key#75){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff8880250c07d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880250c07d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
3 locks held by syz.9.460/9609:
1 lock held by syz.6.464/9633:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5821 Comm: syz-executor Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:409
Code: 20 bd 50 fc 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 11 cb b4 fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c
RSP: 0018:ffffc9000412f438 EFLAGS: 00000002
RAX: 1ffffffff34e1f00 RBX: ffffffff9a70fe80 RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: ffffffff856e9f46 R09: 1ffff11004988046
R10: dffffc0000000000 R11: ffffffff856e9f00 R12: 0000000000000020
R13: 1ffffffff34e2022 R14: 00000000000003fd R15: dffffc0000000000
FS: 0000555584267500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff6604bf48 CR3: 00000000661cc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0x1b1/0x320 drivers/tty/serial/8250/8250_port.c:2100
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline]
serial8250_console_write+0x134c/0x1e00 drivers/tty/serial/8250/8250_port.c:3456
console_emit_next_record kernel/printk/printk.c:3122 [inline]
console_flush_all+0x869/0xeb0 kernel/printk/printk.c:3210
__console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309
vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432
_printk+0xd5/0x120 kernel/printk/printk.c:2457
_btrfs_printk+0x5ae/0x5e0 fs/btrfs/messages.c:248
btrfs_put_super+0x69/0x80 fs/btrfs/super.c:73
generic_shutdown_super+0x139/0x2d0 fs/super.c:642
kill_anon_super+0x3b/0x70 fs/super.c:1237
btrfs_kill_super+0x41/0x50 fs/btrfs/super.c:2100
deactivate_locked_super+0xc4/0x130 fs/super.c:473
cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1413
task_work_run+0x24f/0x310 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f24ebf8e0d7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffdc91c62d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f24ec00e08c RCX: 00007f24ebf8e0d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdc91c6390
RBP: 00007ffdc91c6390 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdc91c7420
R13: 00007f24ec00e08c R14: 000000000004bd4f R15: 00007ffdc91c7460