INFO: task syz-executor:5821 blocked for more than 163 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-[ 364.656805][ T39] task:syz-executor state:D stack:20928 pid:5821 tgid:5821 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x169e/0x54f0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
fuse_chan_wait_aborted+0x15b/0x250 fs/fuse/dev.c:2212
fuse_conn_destroy+0x1e7/0x3e0 fs/fuse/inode.c:1969
fuse_sb_destroy fs/fuse/inode.c:1988 [inline]
fuse_kill_sb_anon+0x1ef/0x270 fs/fuse/inode.c:2001
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
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:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa2e219da57
RSP: 002b:00007ffc7d4e98b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fa2e2232048 RCX: 00007fa2e219da57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc7d4e9970
RBP: 00007ffc7d4e9970 R08: 00007ffc7d4ea970 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc7d4eaa00
R13: 00007fa2e2232048 R14: 0000000000030742 R15: 00007ffc7d4eaa40
INFO: task syz-executor:5825 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21072 pid:5825 tgid:5825 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x169e/0x54f0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
fuse_chan_wait_aborted+0x15b/0x250 fs/fuse/dev.c:2212
fuse_conn_destroy+0x1e7/0x3e0 fs/fuse/inode.c:1969
fuse_sb_destroy fs/fuse/inode.c:1988 [inline]
fuse_kill_sb_anon+0x1ef/0x270 fs/fuse/inode.c:2001
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
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:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6d98aeda57
RSP: 002b:00007ffcb80ed4e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f6d98b82048 RCX: 00007f6d98aeda57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcb80ed5a0
RBP: 00007ffcb80ed5a0 R08: 00007ffcb80ee5a0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcb80ee630
R13: 00007f6d98b82048 R14: 0000000000030efe R15: 00007ffcb80ee670
Showing all locks held in the system:
4 locks held by pr/legacy/17:
#0: ffffffff8e3ba3a0 (console_lock){+.+.}-{0:0}, at: legacy_kthread_func+0x1a3/0x250 kernel/printk/printk.c:3711
#1: ffffffff8e2a1c98 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:305 [inline]
#1: ffffffff8e2a1c98 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline]
#1: ffffffff8e2a1c98 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline]
#1: ffffffff8e2a1c98 (console_srcu){....}-{0:0}, at: console_flush_one_record+0xfa/0xb90 kernel/printk/printk.c:3246
#2: ffffffff9a02d1d8 (&port_lock_key){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffffffff9a02d1d8 (&port_lock_key){+.+.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:717 [inline]
#2: ffffffff9a02d1d8 (&port_lock_key){+.+.}-{3:3}, at: serial8250_console_write+0x179/0x1b90 drivers/tty/serial/8250/8250_port.c:3316
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
6 locks held by kworker/1:1/37:
#0: ffff88801afa9d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284
#1: ffffc90000ac7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285
#2: ffff88802ad18210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802ad18210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899
#3: ffff88802ad14658 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline]
#3: ffff88802ad14658 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
#3: ffff88802ad14658 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#3: ffff88802ad14658 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#3: ffff88802ad14658 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b0/0x4f60 drivers/usb/core/hub.c:5953
#4: ffff88802a952e58 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline]
#4: ffff88802a952e58 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#4: ffff88802a952e58 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#4: ffff88802a952e58 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e0/0x4f60 drivers/usb/core/hub.c:5953
#5: ffffffff8f039320 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x14e/0x1820 drivers/usb/core/hub.c:3067
1 lock held by khungtaskd/39:
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
13 locks held by kworker/u8:5/86:
#0: ffff888067da5938 ((wq_completion)wg-kex-wg1#14){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284
#1: ffffc900015efc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285
#2: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: netif_receive_skb_list_internal+0x501/0xcf0 net/core/dev.c:6428
#4: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#4: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#4: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: ip_local_deliver_finish+0x2ae/0x6f0 net/ipv4/ip_input.c:240
#5: ffff88803b79d160 (slock-AF_INET/1){+...}-{3:3}, at: tcp_v4_rcv+0x25d4/0x2ff0 net/ipv4/tcp_ipv4.c:2242
#6: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#6: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#6: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#6: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock_nested+0x1de/0x3f0 kernel/locking/spinlock_rt.c:65
#7: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#7: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#7: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __ip_queue_xmit+0x5c/0x1bb0 net/ipv4/ip_output.c:477
#8: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#8: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#8: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: ip_output+0x5b/0x450 net/ipv4/ip_output.c:433
#9: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#9: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#9: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0x3c2/0x10b0 net/ipv4/ip_output.c:230
#10: ffffffff8e25f260 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
#11: ffffffff8e3c8160 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#11: ffffffff8e3c8160 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:891 [inline]
#11: ffffffff8e3c8160 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2b3/0x3900 net/core/dev.c:4792
#12: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#12: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#12: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_trylock kernel/locking/spinlock_rt.c:110 [inline]
#12: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x10c/0x2b0 kernel/locking/spinlock_rt.c:118
1 lock held by klogd/5177:
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa6/0x2550 arch/x86/kernel/unwind_orc.c:495
2 locks held by getty/5574:
#0: ffff888037ceb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5821:
#0: ffff8880609ae0d0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880609ae0d0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880609ae0d0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
1 lock held by syz-executor/5825:
#0: ffff88802c8fe0d0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802c8fe0d0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88802c8fe0d0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
1 lock held by syz-executor/8737:
#0: ffffffff8e00a0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline]
#0: ffffffff8e00a0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1677
1 lock held by syz.5.1638/10540:
#0: ffff888050958178 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#0: ffff888050958178 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: fuse_dio_lock fs/fuse/file.c:-1 [inline]
#0: ffff888050958178 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: fuse_direct_write_iter fs/fuse/file.c:1794 [inline]
#0: ffff888050958178 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: fuse_file_write_iter+0x638/0x1130 fs/fuse/file.c:1848
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:162 [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:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 17 Comm: pr/legacy Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:401
Code: e8 3e cc 7d fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 8f 36 e7 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900001679d0 EFLAGS: 00000202
RAX: 1ffffffff3405a00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff9a02d490 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff854721b0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9a02d200 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125b64000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6e4faa64f0 CR3: 000000000e1b6000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1970
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3207 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3272 [inline]
serial8250_console_write+0x120d/0x1b90 drivers/tty/serial/8250/8250_port.c:3357
console_emit_next_record kernel/printk/printk.c:3163 [inline]
console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269
legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245