INFO: task syz-executor:9377 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21544 pid:9377 tgid:9377 ppid:1 task_flags:0x40014c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
__schedule_loop kernel/sched/core.c:6944 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6959
wb_wait_for_completion+0x360/0x680 fs/fs-writeback.c:226
sync_inodes_sb+0x1c9/0xb40 fs/fs-writeback.c:2887
sync_filesystem+0x17a/0x230 fs/sync.c:64
generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
kill_block_super+0x44/0x90 fs/super.c:1723
ext4_kill_sb+0x68/0xb0 fs/ext4/super.c:7403
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1317
task_work_run+0x1d4/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x2300 kernel/exit.c:964
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
__do_sys_exit_group kernel/exit.c:1116 [inline]
__se_sys_exit_group kernel/exit.c:1114 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1114
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9305f8efc9
RSP: 002b:00007ffebc035198 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f9306011def RCX: 00007f9305f8efc9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000010 R08: 00007ffebc032f36 R09: 00007ffebc036450
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffebc036450
R13: 00007f9306011d7d R14: 000055557b4184a8 R15: 00007ffebc037520
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3d960 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d960 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d960 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
7 locks held by kworker/u9:0/52:
#0: ffff8880203dd948 ((wq_completion)hci1){+.+.}-{0:0}, at: process_one_work+0x841/0x15d0 kernel/workqueue.c:3242
#1: ffffc90000bd7ba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15d0 kernel/workqueue.c:3243
#2: ffff88807c0d0dc8 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331
#3: ffff88807c0d00b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x242/0xe30 net/bluetooth/hci_sync.c:5691
#4: ffffffff8f43e808 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2118 [inline]
#4: ffffffff8f43e808 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x340 net/bluetooth/hci_conn.c:1331
#5: ffff88803ee47b38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 net/bluetooth/l2cap_core.c:1762
#6: ffffffff8df433f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#6: ffffffff8df433f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
2 locks held by getty/5590:
#0: ffff888030adc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by kworker/u8:18/7106:
#0: ffff888140add148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x841/0x15d0 kernel/workqueue.c:3242
#1: ffffc90011d17ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15d0 kernel/workqueue.c:3243
#2: ffff88801fbcab98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
#2: ffff88801fbcab98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1796 [inline]
#2: ffff88801fbcab98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1cc/0x350 fs/ext4/inode.c:3021
#3: ffff88807e33c560 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x765/0x1740 fs/ext4/inode.c:810
2 locks held by kworker/u8:39/7143:
2 locks held by syz-executor/9377:
#0: ffff88801fbce0e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88801fbce0e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88801fbce0e0 (&type->s_umount_key#32){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff888024f74820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline]
#1: ffff888024f74820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40 fs/fs-writeback.c:2885
2 locks held by syz.2.1793/11768:
#0: ffff888057ea1ec8 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1063 [inline]
#0: ffff888057ea1ec8 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff888057ea1ec8 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1459
#1: ffffffff8df433f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8df433f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:337 [inline]
watchdog+0xfa9/0xff0 kernel/hung_task.c:500
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
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: 11369 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:delay_tsc+0x5b/0xc0 arch/x86/lib/delay.c:79
Code: 90 49 89 d7 49 c1 e7 20 49 09 c7 4d 29 f7 49 39 df 73 53 bf 01 00 00 00 e8 32 58 3c f6 65 8b 05 cb e5 1f 07 85 c0 74 1c f3 90 01 00 00 00 e8 6b 56 3c f6 e8 86 60 01 00 39 c5 75 0e 0f 01 f9
RSP: 0018:ffffc900038af4d0 EFLAGS: 00000002
RAX: 0000000000000002 RBX: 0000000000000899 RCX: 0000000000000000
RDX: 00000000000000c3 RSI: ffffffff8bbf25a0 RDI: 00000000ffffffff
RBP: 0000000000000001 R08: ffff8881476a0237 R09: 1ffff11028ed4046
R10: dffffc0000000000 R11: ffffffff8b53fa10 R12: 1ffffffff3368c62
R13: 00000000ffffffff R14: 000000c30b9f1042 R15: 00000000000002dc
FS: 00005555629fc500(0000) GS:ffff888125fe2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffe0531bd8 CR3: 000000007e69c000 CR4: 00000000003526f0
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+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3108 [inline]
console_flush_one_record kernel/printk/printk.c:3194 [inline]
console_flush_all+0x6f6/0xb10 kernel/printk/printk.c:3268
__console_flush_and_unlock kernel/printk/printk.c:3298 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3338
vprintk_emit+0x4c5/0x590 kernel/printk/printk.c:2423
_printk+0xcf/0x120 kernel/printk/printk.c:2448
__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:1723
ext4_kill_sb+0x68/0xb0 fs/ext4/super.c:7403
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1317
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fec085902f7
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:00007fffe0532388 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fec08611d7d RCX: 00007fec085902f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffe0532440
RBP: 00007fffe0532440 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffe05334d0
R13: 00007fec08611d7d R14: 000000000005bafd R15: 00007fffe0533510