INFO: task kworker/u8:12:1516 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:12 state:D stack:20864 pid:1516 tgid:1516 ppid:2 task_flags:0x4248060 flags:0x00080000
Workqueue: xfs-cil/loop8 xlog_cil_push_work
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
___down_common kernel/locking/semaphore.c:268 [inline]
__down_common+0x321/0x730 kernel/locking/semaphore.c:293
down+0x80/0xd0 kernel/locking/semaphore.c:100
xfs_buf_lock+0x14d/0x520 fs/xfs/xfs_buf.c:993
xfs_buf_item_unpin+0x1c4/0x770 fs/xfs/xfs_buf_item.c:551
xlog_cil_ail_insert fs/xfs/xfs_log_cil.c:-1 [inline]
xlog_cil_committed+0x9f4/0x1170 fs/xfs/xfs_log_cil.c:995
xlog_cil_push_work+0x2597/0x2b30 fs/xfs/xfs_log_cil.c:1607
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc kernel/workqueue.c:3440[ 727.637605][ T37] worker_thread+0xa53/0xfc0
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz.8.747:12365 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.747 state:D stack:22368 pid:12365 tgid:12364 ppid:10648 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
__flush_workqueue+0x6f6/0x14f0 kernel/workqueue.c:4084
xlog_cil_push_now fs/xfs/xfs_log_cil.c:1725 [inline]
xlog_cil_force_seq+0x228/0x8c0 fs/xfs/xfs_log_cil.c:1927
xfs_log_force_seq+0x196/0x440 fs/xfs/xfs_log.c:2984
__xfs_trans_commit+0x7d3/0xc20 fs/xfs/xfs_trans.c:877
xfs_trans_commit+0x13e/0x1c0 fs/xfs/xfs_trans.c:926
xfs_sync_sb_buf+0x13f/0x230 fs/xfs/libxfs/xfs_sb.c:1490
xfs_ioc_setlabel+0x1de/0x340 fs/xfs/xfs_ioctl.c:1041
xfs_file_ioctl+0x9c5/0x1710 fs/xfs/xfs_ioctl.c:1198
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xff/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f99fa63c819
RSP: 002b:00007f99f888e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f99fa8b5fa0 RCX: 00007f99fa63c819
RDX: 0000200000000000 RSI: 0000000041009432 RDI: 0000000000000005
RBP: 00007f99fa6d2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f99fa8b6038 R14: 00007f99fa8b5fa0 R15: 00007ffd26e13488
Showing all locks held in the system:
1 lock held by khungtaskd/37:
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:12/1516:
#0: ffff88805fc6d938 ((wq_completion)xfs-cil/loop8){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88805fc6d938 ((wq_completion)xfs-cil/loop8){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc900066e7c40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc900066e7c40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
2 locks held by getty/5555:
#0: ffff8880329440a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by kworker/0:5/5882:
#0: ffff8880386be138 ((wq_completion)xfs-sync/loop8){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff8880386be138 ((wq_completion)xfs-sync/loop8){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc900052cfc40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc900052cfc40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
4 locks held by kworker/1:6/7761:
1 lock held by syz.8.747/12365:
#0: ffff888054242480 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537
1 lock held by syz-executor/13309:
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline]
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1678
1 lock held by syz-executor/13383:
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline]
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1678
1 lock held by syz-executor/13678:
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline]
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1678
2 locks held by syz.3.963/14147:
3 locks held by syz.6.961/14154:
4 locks held by syz.9.966/14172:
1 lock held by dhcpcd-run-hook/14187:
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline]
#0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1678
4 locks held by cmp/14208:
3 locks held by udevd/14210:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:401
Code: e8 3e fe 93 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ff 21 fa fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 da 6e f7 05 cc 44 89 f9 80 e1 07
RSP: 0000:ffffc900001679d0 EFLAGS: 00000202
RAX: 1ffffffff332bb00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff9995dd10 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff85308340 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9995da80 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126432000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5546f3e000 CR3: 0000000087618000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1970
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3207 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3272 [inline]
serial8250_console_write+0x120d/0x1b90 drivers/tty/serial/8250/8250_port.c:3357
console_emit_next_record kernel/printk/printk.c:3163 [inline]
console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269
legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245