INFO: task syz-executor:7664 blocked for more than 143 seconds.
Not tainted 6.15.0-next-20250606-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21960 pid:7664 tgid:7664 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:237
__wait_on_bit+0xb6/0x310 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:64
wait_on_bit include/linux/wait_bit.h:77 [inline]
gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1351
gfs2_glock_nq_init fs/gfs2/glock.h:238 [inline]
__gfs2_lookup+0x117/0x270 fs/gfs2/inode.c:987
__lookup_slow+0x297/0x3d0 fs/namei.c:1817
lookup_slow+0x53/0x70 fs/namei.c:1834
walk_component+0x2d2/0x400 fs/namei.c:2138
lookup_last fs/namei.c:2639 [inline]
path_lookupat+0x163/0x430 fs/namei.c:2663
filename_lookup+0x212/0x570 fs/namei.c:2692
user_path_at+0x3a/0x60 fs/namei.c:3127
ksys_umount fs/namespace.c:2147 [inline]
__do_sys_umount fs/namespace.c:2155 [inline]
__se_sys_umount fs/namespace.c:2153 [inline]
__x64_sys_umount+0xee/0x160 fs/namespace.c:2153
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98b178fc57
RSP: 002b:00007fff2c799ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f98b1810925 RCX: 00007f98b178fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff2c799da0
RBP: 00007fff2c799da0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff2c79ae90
R13: 00007f98b1810925 R14: 0000000000046532 R15: 00007fff2c79d050
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
1 lock held by khungtaskd/31:
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5597:
#0: ffff8880349da0a0 (&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+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5835:
1 lock held by syz-executor/5844:
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
5 locks held by kworker/1:3/5856:
4 locks held by udevd/7462:
1 lock held by syz-executor/7664:
#0: ffff88805b2872f8 (&type->i_mutex_dir_key#25){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:882 [inline]
#0: ffff88805b2872f8 (&type->i_mutex_dir_key#25){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833
2 locks held by syz.7.857/10223:
#0: ffff88805667c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffff88805667c130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: tty_write_lock drivers/tty/tty_io.c:939 [inline]
#1: ffff88805667c130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: iterate_tty_write drivers/tty/tty_io.c:958 [inline]
#1: ffff88805667c130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: file_tty_write+0x1d8/0x990 drivers/tty/tty_io.c:1081
4 locks held by syz.3.855/10240:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-next-20250606-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 2156 Comm: kworker/1:2 Not tainted 6.15.0-next-20250606-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: 0x0 (events)
RIP: 0010:rq_of kernel/sched/sched.h:-1 [inline]
RIP: 0010:update_stats_curr_start kernel/sched/fair.c:1397 [inline]
RIP: 0010:set_next_entity+0x15a/0x500 kernel/sched/fair.c:5556
Code: 74 08 4c 89 ff e8 a6 6d 8f 00 4d 89 27 4d 8d a6 78 01 00 00 4d 89 e7 49 c1 ef 03 41 80 3c 2f 00 74 08 4c 89 e7 e8 96 6c 8f 00 <4c> 89 24 24 4d 8b 24 24 48 c7 c0 30 58 a1 8f 48 c1 e8 03 0f b6 04
RSP: 0018:ffffc90004f479a0 EFLAGS: 00000046
RAX: 1ffff1100481401f RBX: ffff8880240a0080 RCX: 00000000000002ea
RDX: 00000000000003f1 RSI: ffff8880240a0080 RDI: ffff8880240a00a8
RBP: dffffc0000000000 R08: ffff8880b873c76f R09: 0000000000000000
R10: ffff8880b873c760 R11: ffffffff81952d40 R12: ffff8880b873bb38
R13: dffffc0000000000 R14: ffff8880b873b9c0 R15: 1ffff110170e7767
FS: 0000000000000000(0000) GS:ffff888125d4d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f202db6a000 CR3: 0000000078b2c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
set_next_task_fair+0x62/0x1d0 kernel/sched/fair.c:13317
put_prev_set_next_task kernel/sched/sched.h:2498 [inline]
pick_next_task kernel/sched/core.c:6341 [inline]
__schedule+0x43c0/0x4d00 kernel/sched/core.c:6738
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
worker_thread+0xa82/0xda0 kernel/workqueue.c:3417
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245