INFO: task klogd:5222 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:klogd state:D stack:24344 pid:5222 tgid:5222 ppid:1 task_flags:0x400100 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7046 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7061
io_schedule+0x80/0xd0 kernel/sched/core.c:7906
migration_entry_wait_on_locked+0x648/0x940 mm/filemap.c:1452
migration_entry_wait+0x20b/0x250 mm/migrate.c:501
do_swap_page+0x455f/0x5950 mm/memory.c:4607
</TASK>
Showing all locks held in the system:
2 locks held by kworker/1:0/24:
1 lock held by khungtaskd/31:
#0: ffffffff8e33cf20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e33cf20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e33cf20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/50:
3 locks held by kworker/u8:4/61:
2 locks held by kswapd0/87:
3 locks held by kworker/u8:6/1098:
3 locks held by kworker/u8:7/1118:
1 lock held by klogd/5222:
2 locks held by udevd/5233:
2 locks held by getty/5623:
#0: ffff8880300520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/5860:
3 locks held by kworker/u8:12/7024:
3 locks held by kworker/u8:14/7298:
3 locks held by kworker/u8:17/7302:
2 locks held by syz-executor/7317:
2 locks held by syz-executor/7454:
3 locks held by kworker/1:7/7637:
2 locks held by syz-executor/7998:
3 locks held by syz-executor/8326:
3 locks held by kbnepd bnep0/9415:
#0: ffffffff8f8cc710 (bnep_session_sem){++++}-{4:4}, at: bnep_session+0x2940/0x2b40 net/bluetooth/bnep/core.c:522
#1: ffffffff8f73f848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#1: ffffffff8f73f848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2142
#2: ffffffff8e3429b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e3429b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
5 locks held by dhcpcd-run-hook/9965:
2 locks held by syz-executor/10002:
4 locks held by kworker/0:9/10005:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5233 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__lock_acquire+0xad3/0xd20 kernel/locking/lockdep.c:5245
Code: 01 00 00 4c 89 f6 89 ea 4c 89 f9 e8 17 38 00 00 85 c0 0f 84 e4 01 00 00 41 f6 46 22 10 75 2e 48 8b 1c 24 4c 89 bb 20 0b 00 00 <8b> 83 28 0b 00 00 ff c0 89 83 28 0b 00 00 83 f8 30 0f 83 64 01 00
RSP: 0018:ffffc900031070c8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff88807c54bc80 RCX: e37c92a613b5a100
RDX: 0000000000000000 RSI: ffff88807c54c7d8 RDI: ffff88807c54bc80
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8173bcb5
R10: ffffc90003107328 R11: fffff52000620e71 R12: 000000001df5900e
R13: ffff88807c54c7b0 R14: ffff88807c54c7d8 R15: bb39787382043d4c
FS: 00007f9192d6e880(0000) GS:ffff8881259f9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd552520457 CR3: 000000007cbae000 CR4: 00000000003526f0
DR0: 0000000002000000 DR1: 0000000000000003 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758