INFO: task syz.7.5164:22081 blocked for more than 149 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.5164 state:D stack:23944 pid:22081 tgid:22077 ppid:19298 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
io_schedule+0x80/0xe0 kernel/sched/core.c:7835
folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1170 [inline]
migrate_folio_unmap mm/migrate.c:1250 [inline]
migrate_pages_batch+0x1864/0x4090 mm/migrate.c:1890
migrate_pages_sync mm/migrate.c:2034 [inline]
migrate_pages+0x20c5/0x2a50 mm/migrate.c:2116
compact_zone+0x26ec/0x4890 mm/compaction.c:2647
compact_node mm/compaction.c:2916 [inline]
compact_nodes mm/compaction.c:2938 [inline]
sysctl_compaction_handler+0x3f3/0x870 mm/compaction.c:2989
proc_sys_call_handler+0x4c9/0x830 fs/proc/proc_sysctl.c:600
iter_file_splice_write+0x9a6/0x10f0 fs/splice.c:736
do_splice_from fs/splice.c:936 [inline]
direct_splice_actor+0x104/0x160 fs/splice.c:1159
splice_direct_to_actor+0x545/0xc80 fs/splice.c:1103
do_splice_direct_actor fs/splice.c:1202 [inline]
do_splice_direct+0x19b/0x2a0 fs/splice.c:1228
do_sendfile+0x547/0x7e0 fs/read_write.c:1372
__do_sys_sendfile64 fs/read_write.c:1427 [inline]
__se_sys_sendfile64+0xdf/0x1a0 fs/read_write.c:1419
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: 0033:0x7f0d5fd8c799
RSP: 002b:00007f0d5dfa4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f0d60006180 RCX: 00007f0d5fd8c799
RDX: 00002000000000c0 RSI: 0000000000000008 RDI: 0000000000000009
RBP: 00007f0d5fe22c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0d60006218 R14: 00007f0d60006180 R15: 00007ffc9d4f7d18
Showing all locks held in the system:
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/38:
#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
4 locks held by kworker/0:2/956:
1 lock held by udevd/5163:
2 locks held by getty/5552:
#0: ffff888036fd80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:3/5807:
3 locks held by kworker/u8:13/9689:
3 locks held by kworker/u8:17/9697:
2 locks held by kworker/1:1/12164:
#0: ffff888019c03938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff888019c03938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc900058f7c40 ((work_completion)(&nft_net->destroy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc900058f7c40 ((work_completion)(&nft_net->destroy_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
3 locks held by kworker/u8:0/13789:
1 lock held by udevd/15501:
#0: ffff88802640f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:961
4 locks held by kworker/u8:4/19391:
3 locks held by kworker/1:2/19684:
#0: ffff888019c03938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff888019c03938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc90005157c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc90005157c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff8880392a7260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490
5 locks held by kworker/u8:21/20461:
2 locks held by kworker/u8:22/20462:
1 lock held by syz.7.5164/22081:
#0: ffff8880638dc480 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1158
2 locks held by syz-executor/23063:
1 lock held by syz.9.5508/23285:
1 lock held by syz.1.5509/23293:
1 lock held by syz.1.5509/23297:
1 lock held by syz.1.5509/23305:
3 locks held by syz.4.5510/23295:
#0: ffff88803ff03cf8 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff88803ff03cf8 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff88803ff03cf8 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
#1: ffffffff8f1c70c0 ((netlink_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:379
#2: ffff888060ccb0c8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nft_rcv_nl_event+0x13d/0xdb0 net/netfilter/nf_tables_api.c:12002
2 locks held by dhcpcd-run-hook/23309:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 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 02/12/2026
RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:407
Code: 9a 94 fc 44 89 f9 d3 e5 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 2c b2 fa fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 57 c6 f6 05 cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc90000167a30 EFLAGS: 00000202
RAX: 0000000000000032 RBX: 0000000000000032 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000000003f8 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff852fdbc0 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffffff999534c0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88812633c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000060030 CR3: 0000000060e80000 CR4: 00000000003526f0
Call Trace:
serial_port_out include/linux/serial_core.h:811 [inline]
serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3192 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x12e1/0x1b90 drivers/tty/serial/8250/8250_port.c:3342
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