INFO: task syz-executor:5820 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22264 pid:5820 tgid:5820 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x1522/0x51d0 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0x164/0x360 kernel/sched/core.c:6964
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+0x13b/0x190 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+0x134/0x2a0 fs/gfs2/inode.c:999
__lookup_slow+0x2b7/0x410 fs/namei.c:1866
lookup_slow+0x53/0x70 fs/namei.c:1883
walk_component fs/namei.c:2229 [inline]
lookup_last fs/namei.c:2730 [inline]
path_lookupat+0x3f5/0x8c0 fs/namei.c:2754
filename_lookup+0x256/0x5d0 fs/namei.c:2783
user_path_at+0x3a/0x60 fs/namei.c:3576
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+0xf6/0x170 fs/namespace.c:2064
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd9e999c1d7
RSP: 002b:00007fff7d5cfad8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007fd9e9a30b3b RCX: 00007fd9e999c1d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff7d5cfb90
RBP: 00007fff7d5cfb90 R08: 0000000000000000 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff7d5d0c80
R13: 00007fd9e9a30b3b R14: 000000000004633e R15: 00007fff7d5d2e40
Showing all locks held in the system:
1 lock held by khungtaskd/32:
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:5/1089:
#0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc90003aefbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90003aefbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
5 locks held by kworker/u8:9/3017:
#0: ffff88801b2df148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801b2df148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc9000bd67bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000bd67bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8f99ddb0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670
#3: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xe5/0xa00 net/core/dev.c:13037
#4: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#4: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:956
2 locks held by getty/5579:
#0: ffff8880308110a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5820:
#0: ffff888057355768 (&type->i_mutex_dir_key#21){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline]
#0: ffff888057355768 (&type->i_mutex_dir_key#21){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1882
3 locks held by kworker/0:6/5966:
1 lock held by syz-executor/7360:
#0: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:956
2 locks held by syz-executor/8295:
#0: ffffffff8f1112c8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f1112c8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8f1112c8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
2 locks held by syz-executor/8316:
#0: ffffffff8f11fc68 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f11fc68 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8f11fc68 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f9ac6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
2 locks held by sed/8520:
#0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa9/0x140 kernel/sched/core.c:647
#1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7121 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:rdtsc_ordered arch/x86/include/asm/tsc.h:57 [inline]
RIP: 0010:delay_tsc+0x71/0xc0 arch/x86/lib/delay.c:72
Code: 00 00 e8 22 fc fc f5 65 8b 05 8b 0e 5d 07 85 c0 74 1c f3 90 bf 01 00 00 00 e8 6b fa fc f5 e8 76 77 01 00 39 c5 75 0e 0f 01 f9 <66> 90 eb bd e8 a6 f7 9d f5 eb dd 4c 29 fb e8 5c 77 01 00 89 c5 0f
RSP: 0018:ffffc9000475f590 EFLAGS: 00000046
RAX: 00000000ed780a31 RBX: 0000000000000993 RCX: 0000000000000000
RDX: 0000000000000105 RSI: ffffffff8c073ae0 RDI: ffffffff8c073aa0
RBP: 0000000000000000 R08: ffff888021fa0237 R09: 1ffff110043f4046
R10: dffffc0000000000 R11: ffffffff8b95c150 R12: 1ffffffff34670a6
R13: 00000000ffffffff R14: 00000105ed780101 R15: 000000000000089d
FS: 000055558607a500(0000) GS:ffff8881256f3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe71f9a06c8 CR3: 000000007a966000 CR4: 0000000000350ef0
Call Trace:
udelay include/asm-generic/delay.h:62 [inline]
wait_for_lsr+0x160/0x2f0 drivers/tty/serial/8250/8250_port.c:1967
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0x1348/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3129 [inline]
console_flush_one_record kernel/printk/printk.c:3215 [inline]
console_flush_all+0x718/0xb20 kernel/printk/printk.c:3289
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3359
vprintk_emit+0x485/0x560 kernel/printk/printk.c:2426
_printk+0xdd/0x130 kernel/printk/printk.c:2451
__ext4_msg+0x2b9/0x2d0 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+0x437/0x4d0 fs/namespace.c:1318
task_work_run+0x1d9/0x270 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+0xed/0x480 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: 0033:0x7f2522d9c1d7
Code: a2 c7 05 bc c3 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 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 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc0989e438 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f2522e30b3b RCX: 00007f2522d9c1d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc0989e4f0
RBP: 00007ffc0989e4f0 R08: 00007ffc0989f4f0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc0989f580
R13: 00007f2522e30b3b R14: 000000000006f09b R15: 00007ffc0989f5c0