INFO: task syz-executor:7174 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:21592 pid:7174 tgid:7174 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:240
__wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:67
wait_on_bit include/linux/wait_bit.h:77 [inline]
gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1268
gfs2_glock_nq_init fs/gfs2/glock.h:252 [inline]
__gfs2_lookup+0x117/0x270 fs/gfs2/inode.c:999
__lookup_slow+0x297/0x3d0 fs/namei.c:1858
lookup_slow+0x53/0x70 fs/namei.c:1875
walk_component fs/namei.c:2221 [inline]
lookup_last fs/namei.c:2722 [inline]
path_lookupat+0x3f5/0x8c0 fs/namei.c:2746
filename_lookup+0x212/0x570 fs/namei.c:2775
user_path_at+0x3a/0x60 fs/namei.c:3567
ksys_umount fs/namespace.c:2058 [inline]
__do_sys_umount fs/namespace.c:2066 [inline]
__se_sys_umount fs/namespace.c:2064 [inline]
__x64_sys_umount+0xee/0x160 fs/namespace.c:2064
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d02b90a77
RSP: 002b:00007fff669a9058 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f1d02c13d7d RCX: 00007f1d02b90a77
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff669a9110
RBP: 00007fff669a9110 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff669aa200
R13: 00007f1d02c13d7d R14: 000000000004e965 R15: 00007fff669ac3c0
Showing all locks held in the system:
1 lock held by khungtaskd/32:
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5580:
#0: ffff8880349640a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
1 lock held by udevd/5851:
#0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639
3 locks held by kworker/0:9/6042:
#0: ffff88813ff11948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff11948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90004f4fbc0 ((work_completion)(&blkg->free_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90004f4fbc0 ((work_completion)(&blkg->free_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2b1/0x6e0 kernel/rcu/tree_exp.h:956
1 lock held by syz-executor/7023:
#0: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8df475f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:956
1 lock held by syz-executor/7174:
#0: ffff88806ba58e88 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline]
#0: ffff88806ba58e88 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1874
1 lock held by dhcpcd-run-hook/10310:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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:160 [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+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7023 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:_find_first_zero_bit+0x9e/0xb0 lib/find_bit.c:149
Code: 89 f7 eb 11 49 8b 06 49 83 c7 08 49 83 c6 08 48 83 f8 ff 75 bb 49 83 c5 40 49 39 dd 73 c8 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 <74> d8 4c 89 ff e8 48 50 9a fd eb ce 66 0f 1f 44 00 00 90 90 90 90
RSP: 0018:ffffc9000214f3f0 EFLAGS: 00000046
RAX: 1ffffffff2683b79 RBX: 0000000000100000 RCX: 0000000000000001
RDX: 00000000b3101a01 RSI: 0000000000100000 RDI: ffffffff9341c3b0
RBP: d59f82b83af619c0 R08: ffffffff8519da25 R09: ffffffff99c0a278
R10: dffffc0000000000 R11: ffffffff8518e200 R12: dffffc0000000000
R13: 000000000000c0c0 R14: ffffffff9341dbc8 R15: ffffffff9341dbc8
FS: 000055556503e500(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564e59c5fbe0 CR3: 0000000064931000 CR4: 0000000000350ef0
Call Trace:
find_first_zero_bit include/linux/find.h:393 [inline]
alloc_lock_chain kernel/locking/lockdep.c:3714 [inline]
add_chain_cache kernel/locking/lockdep.c:3746 [inline]
lookup_chain_cache_add kernel/locking/lockdep.c:3855 [inline]
validate_chain kernel/locking/lockdep.c:3876 [inline]
__lock_acquire+0xb81/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
uart_port_lock_irqsave include/linux/serial_core.h:717 [inline]
serial8250_console_write+0x155/0x1b60 drivers/tty/serial/8250/8250_port.c:3301
console_emit_next_record kernel/printk/printk.c:3129 [inline]
console_flush_one_record kernel/printk/printk.c:3215 [inline]
console_flush_all+0x713/0xb00 kernel/printk/printk.c:3289
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2426
_printk+0xcf/0x120 kernel/printk/printk.c:2451
__ext4_msg+0x293/0x2a0 fs/ext4/super.c:990
ext4_put_super+0xb8/0xc40 fs/ext4/super.c:1295
generic_shutdown_super+0x135/0x2c0 fs/super.c:643
kill_block_super+0x44/0x90 fs/super.c:1722
ext4_kill_sb+0x68/0xb0 fs/ext4/super.c:7444
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0b06790a77
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:00007ffea23e6ff8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f0b06790a77
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffea23e70b0
RBP: 00007ffea23e70b0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffea23e8140
R13: 00007f0b06813d7d R14: 00000000000734c9 R15: 00007ffea23e8180